wind turbine integration in architecture and the built ...

WIND TURBINE INTEGRATION IN ARCHITECTURE AND THE BUILT ENVIRONMENT College of Arts and Architecture

© 2011 The Pennsylvania State University Ute Poerschke, Associate Professor of Architecture ISBN 978-0-615-54244-7 All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopy, recording or any information storage and retrieval system, without prior permission in writing from the publisher.

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INTRODUCTION

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Ute Poerschke

DESIGN INVESTIGATIONS ON BUILDING-INTEGRATED WIND ENERGY: LESSONS FROM AN ARCHITECTURE STUDIO

Ute Poerschke, Malcolm Woollen, Jelena Srebric, Susan Stewart, Timothy Murtha

19 CASE STUDY TWELVE|WEST. PORTLAND, OREGON

Craig Briscoe, John Breshears

39 STRATEGIES OF INTEGRATING WIND TURBINES IN ARCHITECTURE AND THE BUILT ENVIRONMENT Roof Top Justin Konicek, Elizabeth Jenkins

Roof Parapet William Bunk

Double Roof Kelly Ryan

Building Funnel Marjorie Dona, Kara Knechtel

Façade Kyle Schillaci

Building Landscape Interaction Ryan Orr, Michael Stonikinis, Marc Pelletier, Aaron Wertman

PENN STATE RESEARCH TEAM Ute Poerschke, Ph.D., LEED AP, Department of Architecture Jelena Srebric, Ph.D., Department of Architectural Engineering Susan W. Stewart, Ph.D., Departments of Aerospace Engineering and Architectural Engineering Malcolm S. Woollen, Department of Architecture Timothy M. Murtha, Ph.D., Department of Landscape Architecture

PARTICIPATING PENN STATE STUDENTS Justin M. Adamczyk-Delarge, Melissa A. Bernardo, Kyle A. Brown, Alexander D. Bruce, William T. Bunk, Neeraj Chatterji, Clarissa R. Costa Lima, Marjorie S. Dona, Dominique D. Doberneck, Rachel J. Fawcett, Kassandra M. Garza, John Paul Gonzales, Rohan Haksar, Rebecca L. Hopkins, Elizabeth F. Jenkins, Kara M. Knechtel, Justin M. Konicek, Dejan Malenic, Christopher A. McLean, Ryan M. Orr, Alison L. Pavilonis, Marc J. Pelletier, Kelly E. Ryan, Kyle M. Schillaci, Michael Stonikinis, Daniel Vivanco, Eric H. Weiss, Aaron C. Wertman, Kathryn R. Williams.

INTRODUCTION Ute Poerschke Department of Architecture, The Pennsylvania State University

This booklet provides an overview of a research

The first chapter is based on observations of an

and design project that investigates the inte-

academic architectural design studio in the fall

gration of wind turbines in architecture and the

of 2010 and reflects on how to approach wind

urban environment. In the spring of 2010, an

turbine integration in buildings from an archi-

interdisciplinary team of Penn State researchers

tect’s viewpoint. In the second chapter, the

and instructors from the departments of Archi-

design and construction process of the first U.S.

tecture, Architectural Engineering, Landscape

high-rise building with wind turbines installed on

Architecture, and Aerospace Engineering

the roof­—Twelve|West in Portland, Oregon, by

started a collaboration to research building-

Zimmer Gunsul Frasca Architects—is described

integrated wind energy. In contrast to recent

in detail. In the last chapter, main strategies of

research that focuses primarily on technical

integrating wind turbines in architecture will be

performance and the economics of wind tur-

presented through student projects.

bines, the project’s primary objective has been to combine research on wind behavior around

We thank the Stuckeman Collaborative Design

buildings and in the urban environment with

Research Fund, the Penn State Institutes of

design investigations of wind-optimized building

Energy and the Environment (PSIEE) Sustaina-

forms and the aesthetic potential of incorporat-

bility Seed Grant Program, and the Raymond

ing turbines into architecture. It combines tech-

A. Bowers Program for Excellence in Design and

nical, environmental and aesthetic research

Construction of the Built Environment for their

and design studies, thus forming a testing

generous funding of this project. We also thank

ground for new architectural strategies in which

research assistants Alexander Bruce, Neeraj

the utilization of wind turbines is closely linked

Chatterji, Rohan Haksar, Elizabeth Jenkins, and

to building design. In addition, the researchers

Marc Pelletier for supporting the project, and

aim to implement their findings in the teaching

the studio students who played a critical role

of sustainable architecture and technology, as

in demonstrating the importance of design in

well as share them with the wider professional

research.

community and general public.

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DESIGN INVESTIGATIONS ON BUILDING-INTEGRATED WIND ENERGY: LESSONS FROM AN ARCHITECTURE STUDIO Ute Poerschke, Ph.D., Associate Professor of Architecture, Penn State Malcolm Woollen, Assistant Professor of Architecture, Penn State Jelena Srebric, Ph.D., Associate Professor of Architectural Engineering, Penn State Susan Stewart, Ph.D., Research Associate, Aerospace and Architectural Engineering, Penn State Timothy Murtha, Ph.D., Associate Professor of Landscape Architecture, Penn State

Introduction

new architectural strategies of wind turbine

In spring 2010, a team of Penn State research-

implementation in buildings and the urban

ers and instructors from the departments of

environment. Moreover, it intends to link this

Architecture, Architectural Engineering, Land-

research to education for sustainable archi-

scape Architecture, Meteorology, and the

tecture and technology, and aims at sharing

Applied Research Laboratory collaborated to

insights with the wider professional community

launch an interdisciplinary project of building-

and the public.

integrated wind energy (BIWE). In contrast to recent research that focuses primarily on

The following text describes the first step of this

technical performance and the economics of

project, a design studio that explores ideas for

wind turbines, the project’s primary objective is

building-integrated wind energy (BIWE) in mid-

to combine research on wind behavior around

dle-rise buildings in Pennsylvania. Twenty-seven

buildings and in the urban environment with

architecture students developed strategies to

design investigations of wind-optimized build-

integrate wind turbines in their design projects

ing forms and the aesthetic potential of turbine

of a maritime museum in Erie, PA, advised by

integration in architecture. It combines techni-

architects Dr. Ute Poerschke and Malcolm

cal, environmental and aesthetic research and

Woollen. The main objective was to observe

design studies by an interdisciplinary team of

how emerging architects approach this design

architects, architectural engineers, aerospace

task of turbine integration while creating archi-

engineers, landscape architects, and meteo-

tectural entities for a meaningful environment.

rologists. The project forms a testing ground for

The following text summarizes the design pro-

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cess, categorizes different design approaches,

Middle-rise buildings, defined as buildings with

and evaluates the design outcomes concern-

four to seven stories, form a common building

ing their level of building integration and ef-

type in urban and semi-urban locations and

ficiency. Providing the findings to engineers and

their size allows the integration of small wind tur-

landscape architects, the architects intend to

bines that can exploit minimum wind speeds of

receive feedback for potential changes of the

8.5 miles per hour. Skyscrapers were not part of

integration strategies in the design process, and

this investigation, although they are potentially

thus to initiate an iterative process of refinement

able to harvest far more wind energy.

and improvement of the integration of turbines in buildings and the urban environment from

A hypothetical site at the waterfront in the city

technical, social, environmental and

of Erie, PA, was chosen because Erie has one of

aesthetic perspectives.

the highest wind energy potentials in Pennsylvania. The project task was to design a 52,300

Studio Set-up

square foot addition to the existing Erie Maritime Museum, designed by Weber Murphy Fox

For this design studio, we focused on BIWE in

Architects and opened in 1998 as part of the

middle-rise buildings in northwest Pennsylvania

revitalization efforts for the Erie waterfront. Its

with the objective to study the potential of this

main collection piece is the reconstructed Flag-

new approach for our immediate surroundings.

ship Niagara, the famous sailing ship that won Studio field trip to Erie, Pennsylvania

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the Battle of Lake Erie in the War of 1812. The

Comparing this with data collected for a loca-

addition consists of a large workshop space for

tion closer to the site by the Pennsylvania State

the restoration of ships, exhibition spaces and

Climatologist, [1] it was observed that the winds

an education center with auditorium.

at the closer site originate more from the southwest, but still inland. However, this wind rose was

The students initiated their exploration through

still not trustable because between this location

lectures covering wind behavior and wind

and the actual design site is a 40’ lake bluff. The

turbine technology given by architectural engi-

design site is located at the lower side of the

neer Dr. Jelena Srebric and energy engineer Dr.

grade change and therefore may be in a wind

Susan Stewart. Both experts also participated in

shadow to these inland winds. Additionally, the

several design reviews during the semester.

air movement from Lake Erie landwards could

Later in the semester, a symposium was orga-

not be evaluated. In other words, if this had

nized. Invited guests included architects, wind

been a real project, data collection from the

turbine manufacturers, and an artist. These

site for at least one year would have been the

guests gave presentations on their work related

only way to find out the actual wind conditions.

to wind energy and reviewed the students’

Knowing that “the major factor affecting accu-

projects. The symposium will be described later.

racy of energy output predictions is the accu-

At the end of the semester, the final studio

racy of wind speed prediction,”[2] an optimal

reviews became a nexus for new discussions

layout of turbines and accurate prediction of

with wind energy experts from other disciplines

energy output can be achieved only with this

such as aerospace engineering and landscape

information. Improvement of wind condition

architecture.

prediction is an avenue of research we are currently exploring.

Evaluation of Wind on Site

To continue our design studio, we needed to

When wind turbine integration at a particular

“assume” the main wind direction and inten-

site is considered, the understanding of wind

sity. Although this was not fully satisfactory, we

direction, velocity, and frequency is the most

learned from this site assessment process that

important part of a site assessment. For the

missing local wind data could stop the consid-

purpose of a design studio, this was easier said

eration of integrating turbines on site already

than done. The wind data from the airport,

at an early design stage, because a design

as the only data set for the city of Erie down-

team might not be able to wait for the results or

loadable from the U.S. Department of Energy

the client may not want to invest in the data-

website, indicates that the winds at the airport

logging phase. This experience is completely

are mostly from the south (see figures page 6).

different from exploiting solar information,

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which is fully accessible through geometric investigations and weather files consisting, for example, of sky coverage data. Rules of thumb exist for the integration of solar technology—for example tilt angles for photovoltaics and solar heating—but are limited for wind technology. Convenient computational simulation tools are available for solar paths and daylighting, but evaluating or simulating airflow in an urban environment is a difficult and time-consuming task. Therefore, in many respects, wind energy Map showing project site at Lake Erie and wind data sites (airport and location closer to site)

Airport site: wind frequency rose (left) and wind energy rose (right)

integration in the architectural design process is more demanding than that of solar energy.

Approaching the Integration of Wind Turbines in Architectural Design What can be considered good integration? Mounting a high mast on a roof and adding a turbine does not seem to be the correct response for many middle-rise buildings. Integration should involve designing a technical, aesthetic and meaningful unity of building, wind turbine(s), all other spatial and physical building systems, and the environment. Balancing such

Closer site: wind frequency rose (left) and wind energy rose (right).

diverse elements in a project does not mean finding a compromise between them, but instead growing them beyond their singularities to an ideal synthesis. The building design process aims for this idea of integration. In general, publications on BIWE have not yet initiated a discussion about aesthetic quality. Most publications address technical and economic efficiency and are written by engi-

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neers. Investigations concerning the visual and

problems of wind turbine installation on build-

spatial impacts of BIWE on our built environ-

ings and in the urban environment need to be

ment and reflections concerning buildings as

creatively addressed in research and design

meaningful expressions of our society are rarely

inquiry to improve technical output as well as

undertaken. Looking closer into the techni-

aesthetic integration for a meaningful environ-

cal and economic publications on BIWE, the

ment. Such problems are:

conclusions drawn are relatively discouraging. Most publications critically discuss wind turbine

Airflow turbulences

integration in architecture and even doubt its

Urban and suburban areas deal with much

usefulness. Alex Wilson in his article “The Folly of

higher airflow turbulences than open fields.

Building-Integrated Wind,” for example, states

Turbines can capture most efficiently laminar,

that “building-integrated wind doesn’t make

non-turbulent winds. Currently, turbines can-

much sense as a renewable-energy strategy”

not effectively harvest highly turbulent airflow

and that this technology is “usually a bad

and the region of high turbulence in the flow

idea.”[3] Wilson mainly compares big versus

around buildings has generally much lower

small turbines, the latter being even more inef-

wind speeds and thus wind power densities. An

fective when building-mounted: “Perhaps the

additional complication is that this region shifts

greatest impediment to building-integrated

locations on the building with changes in wind

wind energy is the economics. While large free-

direction. When integrating turbines in a design,

standing wind turbines provide the least expen-

it is useful to study turbulences around buildings

sive renewable electricity today, small wind

and on roofs, for example with Computational

turbines are far less cost effective, and when

Fluid Dynamics (CFD) software, and to avoid

small turbines are put on buildings, the costs go

the placement of turbines at building parts

up while the production drops.”[4] Wilson, well

with high turbulences. Locating wind turbines

known for his engagement in sustainable build-

around 30 feet above potential obstacles like

ing, does not clarify where research is needed

trees or buildings is a common rule of thumb for

in the field of turbine integration, and thus his

harvesting laminar winds.

article becomes counterproductive for users, owners, researchers, and designers searching

Noise

for a paradigm shift. Research shows that there

Turbines can produce aerodynamic and struc-

are, in fact, zones of very high velocity in urban

ture-borne sound in a building. Aerodynamic

areas due to local wind channeling.[5] As the

sound is emitted from the spinning of the blades

cost of electricity rises, the incentive to harvest

as the wind passes through. Structure-borne

local renewable energy without transmission

sound emerges from the vibration of a turbine

loss will increase. To prepare for this time, the

propagating in the building structure. Careful

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design of the structural integration of the tur-

processes, safety is currently a great concern

bine with the building can eliminate or dampen

for small wind turbine installations on build-

the latter, while aerodynamic noise is a design

ings. The Small Wind Certification Council has

factor for the turbine and can be lowered, for

recently formed an independent certification

example, by reducing the tip speed ratio of the

body to certify that small wind turbines meet or

turbine (below its optimum value). A deploy-

exceed the requirements of the newly formed

ment of a shroud to encase a wind turbine

AWEA Small Wind Turbine Performance and

could also reduce the aerodynamic noise.[6]

Safety Standard.[7] Currently 25 turbines are in the application stage of going through this pro-

Turbine impact on building structure

cess. Once certified turbines are identified, this

Turbine weight must be considered when de-

will help alleviate many safety concerns.

termining the dimensions of a building structure. The turbine rotation causes vibrations in the

While all of these aspects need to be carefully

mast or substructure that need to be addressed

addressed, there are some thought-provoking

as an additional load for the structure.

advantages of small turbines integrated in buildings and the urban environment as com-

Safety

pared to larger turbines installed in open fields.

Because very few small wind turbine products

First, no or less land or water area is needed for

on the market have undergone certification

BIWE projects. This also implies that additional

Symposium presentation by John Breshears and Craig Briscoe, ZGF Architects

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access roads are not needed, which reduces

their cultural meaning within a building quickly

secondary impacts of farmland reduction and

arose. Questions on the interconnectedness

forest fragmentation. Although the costs for

and relatedness of technical systems and

additional building structure to carry turbine

design idea and the understanding of forming

weight and vibration load are currently larger

an aesthetic and meaningful entity of all build-

than for free-standing turbine towers, smaller

ing elements and requirements were vividly

substructures can be used and foundations or

discussed. The program of a maritime museum

masts might not be needed at all, thus material

and the location at the lakeshore turned out

use can be reduced. The transportation and in-

to be well chosen, because it allowed the

stallation of small turbines is easier as compared

students an inherently conceptual, contextual

to big turbines. BIWE uses short-distance cabling

and even poetic approach to the topic of

and allows for a short-distance grid connection.

wind. While investigating various aspects of

And finally, the scale of small turbines allows for

wind, they connected topics of sailing ships,

a more subtle aesthetic impact on the environ-

history of seafaring, and historic windmills with

ment in comparison to large turbines.

the technical topics of natural ventilation and modern energy generation from wind. The lat-

In the design studio, parallel to discussing tur-

ter became a means to express the former. A

bine siting as a technical problem, the ques-

field trip to the Tall Ships Erie 2010 event was the

tions of aesthetic integration of turbines and

starting point to help students be inspired by Students present their designs to symposium experts

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wind. For future design studios we realized that

art, architecture and sustainable technology,

it is exactly the combination of a technical task

in particular photovoltaics and wind turbines.

and poetic program that can help students un-

Bill Schmitz and Mark Matthews introduced

derstand how technical systems can become

shrouded wind turbine technology and pre-

integral parts of a building design and an artful

sented their products. Tom Zambrano, senior

and meaningful contribution to our world.

scientist for energy and environmental technologies and expert on fluid dynamics, pre-

Symposium At a two-day symposium held at the beginning

sented the development and implementation of technology initiatives particularly related to wind energy.

of the last quarter of the semester, architects, turbine industry representatives and an artist

During the symposium, a general consensus

presented their views on BIWE and turbine

on several points became apparent. Though

products and provided input for the students’

all acknowledged that more research would

projects. It was held on November 12 and 13,

be required to reduce the payback time on

2010, and the following experts were invited:

BIWE, most agreed that wind turbines attracted public attention as a symbol of environmen-

• John Breshears, Architectural Applications, and Craig Briscoe, ZGF Architects

tal responsibility and as an object of kinetic beauty, both values not lead by economic

• Michael Jantzen, Artist

reasoning. John Breshears and Craig Briscoe

• Bill Schmitz and Mark Matthews,

said Twelve|West and its wind turbines became

WindTamer Inc. • Tom Zambrano, AeroVironment Inc.

a landmark in Portland and seeing turbines in the urban environment could help people with behavioral modification of their energy

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First, all invitees gave presentations on their

consumption. Having cooperated with BMW

particular expertise as related to wind energy

Designworks to create wind turbine designs,

in architecture and the urban environment.

Tom Zambrano felt that design was critical to

Architects John Breshaers and Craig Briscoe

gain wide acceptance for BIWE and that archi-

described the design and construction process

tects need to embrace the task of integrating

of the ZGF project Twelve|West in Portland,

wind energy technology in architecture and

Oregon, the first urban high-rise building in the

the built environment. Michael Jantzen con-

United States with four wind turbines on the

firmed that his pavilions with monumental wind

roof. Michael Jantzen, an internationally known

turbines were intended to highlight the kinetic

artist interested in the sculptural potential of

quality of this technology and its environmental

wind turbines, illustrated how his work merges

promise. His standpoint that the aesthetic value

of our built environment must precede ques-

transformation of the vibration created by the

tions of efficiency stood in contrast to the one

wind pressure on a façade or mast into

of Mark Matthews, for whom economic ques-

electrical power.

tions concerning renewable energies need to be answered first. Through these discussions, the

As far as the integration of HAWTs is concerned,

role of the architect as the advocate of both

two designs installed them on a roof, five on

standpoints was well elucidated.

separately standing masts, three integrated in a façade surface, and one in a building tunnel. As far as the integration of VAWTs is concerned,

Categorization of Design Approaches

four used them on the roof, one on separately

Of the twenty-seven designs that integrate

standing masts, two in a funneling building

wind turbines, nine (33%) used horizontal-axis

shape, and nine laid them horizontally. Six main

wind turbines (HAWT), fourteen (52%) vertical-

strategies of integrating wind turbines became

axis wind turbines (VAWT), and two (7.5%) both

apparent during the design developments.

HAWT and VAWT. Two designs (7.5%) didn’t use

They are presented in the figure below and

wind turbines at all, but investigated instead the

further discussed in the following.

ROOF TOP

ROOF PARAPET

DOUBLE ROOF

BUILDING FUNNEL

FACADE

BULIDING-LANDSCAPE

Six main strategies of wind turbine integration used in the design studio

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1. Wind Turbines Mounted on Roof Top Nine projects have HAWTs and VAWTs mounted on roofs. The sample project by Justin Konicek uses four VAWTs laid horizontally, approximately fifteen feet above the flat roof. The siting might have the disadvantage that the turbines are too close to the flat roof where wind power density is low and high turbulence may occur. Considering the rule of thumb mentioned previously, the height of the turbines should be around thirty feet above the roof to get into the laminar flow field. This is on the same order of the building height itself in this case. Since Strategy 1: VAWTs mounted horizontally on flat roof. Project by Justin Konicek (section and model).

the design strategy of forming a horizontal line of wind turbines parallel to the roof fits well with the horizontality of the entire building, one might test if this line of turbines can be raised even higher above the roof. 2. Wind Turbines Mounted on Roof Parapet Six studio projects have wind turbines mounted on the roof parapet where wind speed is higher than at the façade or on the roof itself. The strategy was inspired by AeroVironment projects realized throughout North America. Three of the student projects used VAWTs horizontally laid to form a line parallel to the roofline. Through this arrangement, the rotation of the turbine blades parallels the roofline and is thus perceived visually higher integrated than a row of propeller-shaped HAWTs, in which the circular rotation of the blades is perpendicular

Strategy 2: VAWTs mounted horizontally on windwardoriented roof parapet. Project by William Bunk (elevation and model).

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to the roofline thus standing in contrast to the horizontal line. The placement of eight VAWTs in the sample project by William Bunk is clearly

defined between clerestories at the highest and windiest location of the building. Lower building parts in front of the parapet might cause turbulences and need further investigation and maybe removal. 3. Double Roof System Two projects explored the idea of exploiting the Venturi effect by funneling wind through a double roof system and integrating turbines within the two roof layers. The sample project by Kelly Ryan uses six magnetically levitated VAWTs, which are presented as a technology that reduces noise, vibration and energy loss and that can be used for low wind environments. The exhaust of the natural ventilation system into the roof gap produces a lowpressure side thus increasing the wind draft and

Strategy 3: Magnetically levitated VAWTs placed in a double roof system. Project by Kelly Ryan (section and model).

turbine efficiency. 4. Funneling Building Shape Similar to the strategy mentioned before, this approach of wind turbine integration exploits the Venturi effect by creating a wind-funneling situation within the building, however, not in a double roof system. Three projects explored this strategy, two of which used VAWTs. The sample project by Marjorie Dona creates the funnel within a three- story glass cube that is placed on a flat roof. Angling the sides of the funnel increased the captured wind area.

Strategy 4: Wind turbines in a wind-funneling building shape. Project by Marjorie Dona (section and model).

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Strategy 6: Wind turbines integrated in landscape. Project by Ryan Orr (site plan and model).

A large sidewall channels more wind towards Strategy 5: HAWT integrated in façade. Project by Kyle Schillaci (section and model).

the turbine and it needs to be further studied

5. Façade Integration

causes unwanted turbulences. Being the tallest

The idea behind the façade integration ap-

structure of all projects with a turbine placed

proach is to not only capture wind flow from

at the highest point, one might expect that the

the main wind directions, but also from the

wind energy output would be the greatest. This

ascending airflow at the façade. Two projects

needs further study.

if this increases wind flow or, just the opposite,

from the studio might fit in this category with

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HAWT and VAWT both used. The sample pro-

6. Building - Landscape Interaction

ject by Kyle Schillaci uses one comparatively

Five projects follow the approach to place

large HAWT at the top of the building design.

wind turbines adjacent to the designed build-

ing in the landscape (including the water) while

potential for further engineering inventions, pro-

creating a contextual relationship to the build-

moting renewable energy, symbolizing a future

ing and the surroundings. The sample project by

entirely fueled by clean energy, visualizing the

Ryan Orr uses six HAWTs to create a horizontal

environmental context (‘a windy place’), and

‘sky level’ that reflects the ‘water level,’ while

inspiring kinetic objects. While all the compo-

both define a space in between in which the

nents of an environmentally responsible build-

design takes place. In the design, the verticality

ing are not entirely visible or understandable to

of the masts of turbines and ships is contrasted

the public, wind turbines, on the other hand,

with the horizontality of water, land and sur-

are supremely understandable. They catch the

rounding buildings—poetically emphasizing the

eye, offer a compelling statement about an

program of a maritime museum.

owner’s responsibility for the environment, and invite curiosity for the unseen sustainable com-

Conclusions and Next Steps

ponents of the building. They can also represent the productive power of larger turbines in

The role wind energy will play in the sustainable

open spaces and promote a new sensitivity to

fulfillment of our energy demands is well

local environmental conditions. While discuss-

known.[8] The question about the particular

ing what cost-effectiveness for our society really

contribution that architecture and the urban

means, people might invest in BIWE for these

environment will make in this challenge has yet

reasons. Meanwhile, we anticipate that BIWE

to be answered. The integration of small wind

will continue to be the subject of increasingly

turbines in buildings is just at its infancy, and

high profile experimentation, design investiga-

investigations about optimized energy per-

tion, and public fascination.

formance and aesthetic integration have just started to become research and design foci for engineers and architects. Similar to the development of building-integrated photovoltaics (BIPV) more than twenty years ago, the current approaches to BIWE are accompanied by both enthusiasm and criticism. Over the years, BIPV has successfully integrated topics of energy effectiveness with visual and

CFD simulation of a box-shaped project (such as on page 12) at the Erie site. The simulation shows the increased wind velocity at the building parapets.

spatial appearance of our environment and

Closing the gap between evolving technical re-

can serve as a model for further investigations

search and known design solutions will depend

in BIWE. Wind generation on buildings has the

on interdisciplinary collaboration. At its best, this

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collaboration process can be described as an iterative loop between engineers and architects that starts with the exploration of feasibility of wind energy harvesting, continues with alternative design developments and their simulations and evaluations of turbines and buildings, and ends with refined efficiency and formal integration. In the next steps of the project, we are currently investigating how to better simulate and map wind flow by taking the site at Erie and representative designs from the Erie design studio. While simulating single designs is one effort, another approach currently under way is to integrate geo-design principles and geospatial tools to analyze the overall three

Acknowledgements This project is funded by the Stuckeman Collaborative Design Research Fund, the Penn State Institutes of Energy and the Environment (PSIEE) Sustainability Seed Grant Program, and the Raymond A. Bowers Program for Excellence in Design and Construction of the Built Environment. We also thank research assistants Rohan Haksar, Neeraj Chatterji, and Alexander Bruce for supporting the project, and all studio students who demonstrated the critical role that design plays in research. An earlier version of this text was published in the 2011 Proceedings of the American Solar Energy Society, ASES.

dimensional space of urban wind to inform site selection, building orientation and the building envelope, and then to adapt the categories of student designs and study them within this system. Moreover, we are taking sonic anemometer data on a six-story campus building to help build the base of knowledge on the turbulence

Notes [1] Pennsylvania State Climatologist: http:// climate.met.psu.edu/www_prod/ida/index. php?t=3& x=dep&id=DEPERI [accessed 9/15/2010].

levels experienced in the built environment with

[2] Encraft Warwick Wind Trials Project 2009.

the intent of providing insight into proper tur-

Available at: http://www.warwickwindtrials.org.

bine design and selection for this application.

uk/index.html [accessed 10/2/2011], p.33.

There are many more avenues for research, such as economic or policy questions, and we like to invite researchers and practitioners to form an even wider collaborative team with us.

[3] Wilson, Alex, “The Folly of Building-Integrated Wind,” Environmental Building News, vol.18, no.15, 2009, pp.1-15, esp. p.1. [4] Ibid., p.12. [5] Johnson, G.T., and Hunter, L.J., “Some insights into typical urban canyon airflows,” Atmospheric Environment, vol.33, no.24-25, October 1999, pp.3991-3999.

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[6] Bahadori, Mehdi N., “Wind Tower Augmen-

Wilson, Alex, “The Folly of Building-Integrated

tation of Wind Turbines,” Wind Engineering,

Wind,” Environmental Building News, vol.18,

vol.18, no.3, 1984, pp.144-151.

no.15, 2009, pp.1-15.

[7] http://www.smallwindcertification.org/ [accessed 2/2/2011].

Participating Students

[8] See: http://www.20percentwind.org/ [ac-

Justin M. Adamczyk-Delarge

cessed 2/2/2011]

Melissa A. Bernardo Kyle A. Brown

References

Alexander D. Bruce William T. Bunk

Bahadori, Mehdi N., “Wind Tower Augmenta-

Clarissa R. Costa Lima

tion of Wind Turbines,” Wind Engineering, vol.18,

Marjorie S. Dona

no.3, 1984, pp.144-151.

Dominique D. Doberneck

Encraft Warwick Wind Trials Project 2009. Available at: http://www.warwickwindtrials.org.uk/ index.html [accessed 10/2/2011].

Rachel J. Fawcett Kassandra M. Garza John Paul Gonzales Rebecca L. Hopkins

Johnson, G.T., and Hunter, L.J., “Some insights

Elizabeth F. Jenkins

into typical urban canyon airflows,” Atmospher-

Kara M. Knechtel

ic Environment, vol.33, no.24-25, October 1999,

Justin M. Konicek

pp.3991-3999.

Dejan Malenic

Mertens, Sander, Wind Energy in the Built Environment. Concentrator Effects of Buildings, Dissertation TU Delft 2006.

Christopher A. McLean Ryan M. Orr Alison L. Pavilonis Marc J. Pelletier

Pennsylvania State Climatologist: http://cli-

Kelly E. Ryan

mate.met.psu.edu/www_prod/ [accessed

Kyle M. Schillaci

9/15/2010]

Michael Stonikinis

Small Wind Certification Council: http:// www.smallwindcertification.org/ [accessed 10/2/2011]

Daniel Vivanco Eric H. Weiss Aaron C. Wertman Kathryn R. Williams

Stankovic, Sinisa, Campbell, N., Harries, A., Urban Wind Energy, London: Earthscan, 2009.

17|

Photo © Timothy Hursley

CASE STUDY TWELVE|WEST PORTLAND, OREGON Craig Briscoe, Associate Partner, ZGF Architects LLP John Breshears, President, Architectural Applications

Building-Integrated Wind Turbines

In retrospect, the path can be mapped as

To judge from the pages of any recent

four parallel strands of investigation that

architectural magazine, incorporating small-

are then synthesized into a result: (1) At the

scale wind turbines into buildings has become,

geographical scale, is there enough wind to

at least on paper, very fashionable. The mayor

operate the turbines effectively? (2) At the

of New York recently put forth ambitious

building scale, where should those turbines be

proposals for widespread implementation

located to achieve the maximum benefit? (3)

in his city. Yet wind behavior in an urban

At the equipment scale, what type of turbine

environment is immensely complex and almost

would perform the best? (4) What pragmatic

universally over-simplified in these attempts. A

constraints need to be resolved in order to

quintessential example of Chaos Theory as it

turn this investigation into a built reality? Pursuit

has developed in this century is the transition

of these parallel strands has led, often quite

of a fluid flow (air or water) from laminar

unexpectedly, to encounters and collaboration

to turbulent—a process that is still not fully

with some of the world’s foremost experts in

understood. Only one widespread study on

turbine aeronautics.

building-integrated wind power­—The Warwick Wind Trials—has been conducted to date,

(1) A study of wind behavior and its statistical

and it is inconclusive at best. The turbines atop

characterizations demonstrated that turbine

Twelve|West, in Portland, Oregon, are an

power generation is highly sensitive to slight

attempt to move beyond a simplistic approach

wind variations. The wind resource available at

to a truly informed application of building-

the site and actual height of the turbines (more

integrated windpower and, in so doing, help to

than 270 feet above ground on a 22-story

create a roadmap for others to follow.

building) was evaluated with the assistance

19|

of a Dutch expert. Utilizing both available

engineer led to an invitation to the National

weather data (gathered from the Portland

Wind Technology Center in Boulder, Colorado,

Airport, nearby Portland State University and a

where a work session with the Director and wind

NASA weather station) and information on the

turbine research staff produced suggestions for

local urban topography (utilizing Google Earth

solving acoustic concerns, ideas for monitoring

and published census data), an increase in

the wind behavior and resulting turbine

available wind power of roughly 35% over the

performance post-construction, and general

airport data was predicted.

encouragement for the approach and the endeavor. Local and state agencies, initially

(2) A chance meeting with founding members

disinterested in the idea, provided project

of AeroVironment, the innovative firm

funding after reviewing the full investigative

responsible for the design of the Gossamer

process.

Albatross, led to studies with a physical model in the wind tunnel at Oregon State University.

Construction of the project was completed,

A visual understanding of how the predicted

and initial turbine operation begun, in August

winds would flow over the Twelve|West building

of 2009. What follows is a description of the

demonstrated where on the building the

process of design which led to this innovative

turbines would have their greatest impact. The

installation.

subsequent results were utilized to determine how many turbines should be used, where to place them, and the ideal turbine design.

Establishing Conditions Near the Ground

(3) The search for a turbine manufacturer

The most widely available wind data in the

illustrated how few firms are actually producing

United States comes from the National Weather

functional turbines suited and certified for use in

Service, which maintains anemometers at every

the built environment. The ultimate choice, the

major airport. While years of data are available,

Skystream 3.7 turbine produced by Southwest

the collection sites on open airfields do not

Wind Power, was then integrated into the

accurately reflect conditions in the city.

design, with structural and electrical system modifications and maintenance access all duly considered.

Characterizing the Wind Data The distribution of average hourly windspeeds

|20

(4) Resolution of remaining questions continued

for any given location falls into the form of

through the production of working drawings.

a particular bell-shaped curve known as a

Another chance meeting with a turbine

Weibull Distribution, named for the Swedish

mathematician Waloddi Weibull. Incidentally,

2.8, however, changed the power output of a

an individual’s likelihood of experiencing

turbine by as much as 50 percent.

a heart attack, the test scores of a high school math class, and any number of other statistically probable events can be described by this curve. The curve can be described by

How Much Wind is There 22 Stories in the Air?

two simple numbers: the average of the wind

Wind behavior can vary significantly with small

speeds throughout the year, and the ‘shape’

changes in location, limiting the reliability of

parameter, describing how short and wide or

wind resource data measured anywhere but

tall and pointed the curve is.

the actual turbine site. The friction effect of the earth’s surface creates a ‘no-slip’ condition, causing a wind velocity of zero at ground level.

Examining the Local Information

Over open terrain, the velocity profile of wind

Locating long-term data from anemometers

as a function of height above the ground is

in downtown Portland proved difficult, despite

relatively predictable and defined as the log-

the design team contacting every television

law function as diagrammed below right. In

meteorologist in the area. Data sets were taken

an urban context, buildings produce drag and

from the local airport and a local university

turbulence, causing a much more complex

building, neither of which were truly

situation, shown below left.

representative of the proposed turbine location. The two sets of data, however,

Predominant Wind Directions

pointed out the sensitivity of wind speed distribution on power generation. The data

The local wind data, when plotted into a Wind

sets had identical annual averages of 3.6 m/s.

Rose, revealed two fairly consistent, seasonally

A difference in the shape parameter of 1.7 to

varying wind directions. During the summer

Wind velocity profiles in the built environment and over open ground

21|

Wind rose Portland, Oregon

PREDOMINANT SUMMER WIND DIRECTION

PREDOMINANT WINTER WIND DIRECTION

months, the winds tend to approach the site

doctoral dissertation at the Technical University

from the northwest, while in the winter they

of Delft dealt with wind energy in the built

originate through a slightly wider range of

environment. Mertens applied his wind data

south-southeasterly directions.

translation approach to the measured data. This approach accounts for the step change in

Dutch Expertise

as it enters an urban area by approximating

In order to predict the wind at the top of

the revised internal boundary layer height and

a 270-foot tall building in a unique urban

accounting for the effects of turbulent mixing

context the design team engaged Sander

downstream from this step change.

Mertens, a Dutch wind consultant whose

|22

surface roughness encountered by wind flow

location avg.

university avg.

airport and

Estimated electricity production

3500

3500

3000

3000

2500

2500

2000

2000

turbine

Portland Windspeed Distribution

A n t i c i pAt E D p o W E R p R o D U c t i o n The predicted wind speed and Weibull distribution at the top of the building yielded estimated power production 40% higher than what was indicated by locally measured

Hours/Yearr

Hours/Yearr

weather data.

TMY2 Windspeed Data PSU2 Measured Data

1500

1500

Mertens_2

1000

1000

500

500

0

0

0

1

2

0

1

3

2

4

5

3

6

4

5

6

average

Windspeed (m/s) shape output average�

(m/s)

param.

(kWh/year) speed speed��

3.6

1.7

1 8(m/s) 20

UnivERSity 3.6

2.8

1180

2.6

3060

location AiRpoRt TURBINE SITE

4.9

7

8

7Windspeed 8 9 (m/s) 10

9

11

shape� parameter

10

12

11

13

1.7

1826

University

36 3.6

28 2.8

1180

TurbineSite

4.9

2.6

3067

Mathematical Data Translations Two sets of data were translated from their

13

14

annual� generation (kWh) generation��(kWh)

3.6

Airport

12

14

Distribution of the wind speeds at the rooftop turbine location.

measured locations to the turbine site through a set of mathematical transformations that, simplistically speaking, accounted for an effective ‘false floor’ (the ‘meso wind speed’) and surface roughness to derive the predicted characteristic parameters for the Weibull

Anticipated Power Production Mertens’ predicted wind speed and Weibull distribution at the top of the building, graphed above, yielded estimated power production

23|

fourty percent higher than what was indicated

about the cold call, and after establishing that

by locally measured weather data.

this organization was, in fact, responsible for some of the major engineering triumphs of the

Aeronautical Engineering Consultant With the wind resource established at a large

late twentieth century, the firm was contracted to help solve the new question facing the design team.

scale, the design team turned to asking where to mount the turbines on the building. Through serendipity a rendering of the building fell into the hands of Tom Zambrano, a senior research

|24

W i n D t U n n E l Af

on the West coast lookin

suitability, availability an

Question: Where is the Ambient Wind Over the Building?

scientist at aeronautical and alternative energy

One of the first things the aeronautical

engineering firm AeroVironment. Intrigued by

engineers helped with was clarifying the

the project Zambrano called and said they

question to be asked. The key to locating the

would like to work on the project to “learn how

turbines properly was in understanding the wind

architects think.” After some initial skepticism

flow over the building. Determining this required

on an aged but well-equ

south of the building loc neering department.

E x p E R i m E n tA l S ous “flow visualization”

including high-speed ph smoke over the model,

a large scale physical model of the building, time in a wind tunnel, and some instruments which the aeronautical engineers could provide.

Wind Tunnel After contacting every wind tunnel on the West coast looking for a magical combination of suitability, availability and affordability, the team settled on an aged but well-equipped wind tunnel two hours south of the building location at Oregon State University in Corvalis.

Experimental Study The team tried numerous “flow visualization” techniques in the wind tunnel, including highspeed photography recording the flow of smoke over the model, illuminated by lasers.

inStR was led

aeronau

consiste

of thread

toy airpl

These in

complex “Instruments” for wind tunnel testing

team to on wind

will caus 25| effects o

the amb

Wind tunnel testing

Instruments In the end, the most important work was led by Tom Zambrano and Tyler MacCready of AeroVironment, arguably two of the finest aeronautical engineers in the world, whose instruments consisted of replacement fishing rod tips with various bits of thread, cassette tape, and propellers from toy airplanes. These instruments, pictured below, proved remarkably sensitive to the complexities of wind flow over the model and allowed the team to locate the elevation at which the building’s effect on wind flow ended. Below these elevations the structure will cause turbulence and eddies,

|26

THROUGH-FLOW ZONE SHEAR PLANE

TURBULENT ZONE

Loation of the shear plane governs minimum advisable turbine height

i n S t R U m E n t S In the end the most important work

t h E S h E A R p l A n E l o c A t i o n S The primary

was led by the collaborators, arguably two of the finest

task of the wind tunnel exercises then, apart from gaining

aeronautical engineers in the world, whose instruments

much better qualitative understanding of the wind flow

consisted of replacement fishing rod tips with various bits

patterns over the building, was to determine the location of thread, cassette tape, and propellers from of the shear The planeShear for each of the two seasonally domiPlan Locations which will have negative effects on turbine toy airplanes. nant wind directions. Location of the turbines above the performance; above these elevations the The primary task of the wind tunnel exercises shear planes is critical to their power generation, by virtue ambient wind will flow freely and turbines will then, apart from gaining much better These instruments proved remarkably sensitive to the of the higher energy embodied in the wind, and their experience optimum conditions. qualitative understanding of the wind flow complexities of wind flow over the model and allowed the endurance, which can be substantially shortened by the patterns over the building, was to determine team to locate the elevation at which the building’s effect repeated hammering of turbulent wind flow. the location of the shear plane for each of on wind flow ended. these elevations the structure 3DBelow Shear Plane Framework the two seasonally dominant wind directions. will cause turbulence and eddies which will have negative The elevation of the separation between Location of the turbines above the shear planes effects on turbine performance; above these elevations turbulence near the roof and ambient flow is critical to their power generation, by virtue of the ambient wind will flow freely and turbines will proabove, called the Shear Plane, was measured the higher energy embodied in the wind, and duce at their best.at grid points over the roof plane of the model. their endurance, which can be substantially Two sets of measurements were taken, one for shortened by the repeated hammering of each dominant wind direction in Portland. turbulent wind flow.

27|

Identified shear plane locations with: original turbine array (left) and revised array (right)

Somewhat counterintuitively, for a building with

placement were sound but not perfect. The

this aspect ratio and sharp corners, the location

initial location was very near a pronounced

of the shear planes remain fairly constant even

‘valley’ formed by the intersection of the two

with changing wind speeds. This allowed the

planes that put most of them into the desired

team to be fairly confident that once these

wind flow zone. Three of the five were well

critical surfaces were located, they would

placed to be above the two shear planes,

enable us to locate the turbines correctly for

while the two western-most turbines were

the entire year.

below the shear plane for the southeasterly winter winds (turbines below the red plane in

Optimized Turbine Array and Locations

|28

the image above left).

Following the wind tunnel studies, the shear

To ensure that the entire turbine array is

plane measurements were then modeled into

always above the turbulent and eddying air,

two 3D meshes by the architects. This work

a planned fifth turbine was eliminated and

produced a visual tool that clearly indicated

the four remaining turbines were shifted to the

good and bad locations for the turbines.

east. As currently designed, all four turbines are

Overlaying the shear plane framework on the

predicted to capture smooth, ambient wind

initially proposed turbine installation indicated

flows from the two dominant wind directions,

that the team’s instincts about turbine

image above right.

SAVONIUS

DARRIEUS

HORIZONTAL

Three typical turbine types

Explore Turbine Types: Savonius, Darrieus, Horizontal Axis Another aspect of finding the right turbine

by the fact that at least one of the blades is

was understanding the three dominant wind

always turning against the wind, limiting the

turbine types. Savonius turbines have solid wind

overall turbine efficiency. While vertical-axis

scoops which limit their efficacy in wind power

turbines in general benefit from being able to

production; because they do not act as airfoils,

receive wind from any approaching direction,

they operate by drag only, literally being

Darrieus models can be difficult to start up from

‘pushed’ around by the wind. Consequently,

a stationary position.

the rotational velocity at their outermost point cannot move faster than the wind, and they

Horizontal-axis turbines are the most efficient

loose efficiency quickly at higher wind speeds.

design as all their airfoil blades benefit from the oncoming wind. Mechanical complexity

Darrieus turbines also have a vertical axis but

is added in that the turbine must turn to face

employ air foils to harness lift effects, allowing

changing winds (known as ‘yawing’), but the

them to turn faster than the wind. The increased

increase in power production and long-term

speed improves the energy production of

industry experience with the design more than

Darrieus turbines, but they are hampered

make up for this complexity.

29|

Spec Spec cific cificPower Power( (kW kW W/m2 W/m2of ofswep swep pt ptarea area) )

0.5 0.5 0.45 0.45

t tU UR RB B ii n nE E p po oW WE ER R c cU UR Rv vE ES S -0.4 0.4 Sp pE Ec c ii f f ii c c p po oW ER R (( k kW Wh h // m m2 2 o of f S SW WE Ep pt t A AR RE EA A )) S WE 0.5 0.5

tU R B iCurves n E p- o W E RPower c U (kWh/m2 R v E S -of 0.45 Turbine Power Specific Swept Area) Spec Spec cific cificPower Power((kW kW W/m2 W/m2of ofswep swep pt ptarea area))

0.45

SpEcific poWER (kWh/m2 of SWEpt AREA)

Spec cific Power ( kW W/m2 of swep pt area )

0.5 0.45 0.4 0.35 0.3 0.25 0.2

0.4 0.4

0.35 0.35 0.3 0.3 0.25 0.25 0.2 0.2

0.35 0.35

pER

0.3 0.3

a num

0.25 0.25

able

0.2 0.2

outp

0.15 0.15

WS4

0.1 0.1

m/s.

rang

0.05 0.05 0 0

0.15 0.15 0.1 0.1

focus 0 0

1 1

0 0

0.1

0 0

1 1

2 2

3 3

4 4

5 5

6 6

0 2

3

4

5

6

7

8

9

10

Windspeed (m/s )

5 5

6 6

7 7

11

WES5 Tulipo Tulipo(H) (H) WES5 Tulipo (H) WES5 SW Windpower Skystream (H) (H) SW Skystream (H) SW Windpower Windpower Skystream

12 Predicted 13 14 Windspeed Predicted Windspeed Range Range (90% (90% probability) probability)

9 9

10 10

11 11

tion 12 12

WES5 WES5 Tulipo Tulipo (H) (H)

SW SW Windpower Windpower Skys Skys

QUE Will

prod

for h

Windside WS4 (V-S)

WES5 Tulipo (H)

have

Turby (V-D)

SW Windpower Skystream (H)

ca? D

us vi

Predicted Windspeed Range (90% probability)

What is the Best Turbine for the Application?

The small-wind turbine industry seems to attract brilliant engineers and charlatans in equal measure. Many turbine developers make

|30

8 8

Windspeed Windspeed (m/s (m/s ))

Predicted Windspeed Range Predicted Range 7 8 9 10 11 14 7 8 9 10 Windspeed 11 12 12 13 13 14 (90% Predicted Windspeed Range (90% probability) probability) Windspeed (m/s )) Windspeed(90% (m/sprobability)

Windside WS4 WS4 (V-S) (V-S) Windside Turby (V-D) (V-D) Turby 1

4 4

Turby Turby(V-D) (V-D) Turby (V-D)

0.05

0

3 3

Windside WS4 (V-S) Windside Windside WS4 WS4 (V-S) (V-S)

0.05 0.05

0.15

2 2

Questions for the Manufacturers

claims of turbine performance that defy the

A series of simple screening questions for

laws of physics. These were easy to eliminate

manufacturers was quickly established: Will they

from consideration for the project. Many others

answer the phone? Are their turbines actually in

publish theoretical power curves (indicators

production? How many have been placed in

of performance at various wind speeds) that

service, and for how long? Have they heard of

have not been tested. Still others seem to be

UL? Do their products have other certifications?

ignorant of Underwriters Laboratories (UL) and

Do they export to North America? Do they

other certification programs for equipment

have a warranty? Would they be willing to let us

connecting to a building’s electrical system.

visit an actual installation?

Performance Curves Performance curves for a number of buildingscale turbines appearing to be available on the market are compared in the graph on the left. This comparison, when overlain with the anticipated range of wind speeds at the proposed location, helped to focus the performance-based aspects of the turbine selection process.

Skystream Turbine After an exhaustive search the team chose a new 12-foot diameter horizontal-axis turbine designed and manufactured by Southwest Windpower, a company with a long history in small-wind turbines. The Skystream 3.7 turbine features a passive yaw (rotation) system to orient the turbine blades to the wind and a downwind blade design that eliminates the need for a tail or other orienting device. The striking scimitar-shaped blades are designed for maximum energy production at low wind speeds and to minimize turbine noise. The turbine has undergone extensive testing at the National Wind Technology Center and has been approved by major certification programs.

Skystream turbine prototype in testing at Boulder, Colorado

31|

c o l l A B o R At i o n W i t h S o U t h W E S t W i n D p o W E R - m A n U fA c t U R E R o f t h E S k y S t R E A m Marketed to date largely for semi-rural

Acoustic Concerns locations, the turbine masts are designed to be pivoted

collABoR

WinDpoWE

SkyStREAm

locations, the tu into place by virtue a ‘gin pole’, at a cable, and a truck. Long a concern of of wind turbines all scales, into place by vi A different solution wasand required to provide the potential for noise vibration in themaintenance A different solu access on project the building given the difficulty of getting proposed was roof, particularly worrisome access on the b a truck onto location the roof. Together with premiumthe turbine manufacdue to their directly over a truck onto the turer,penthouse a portable manual winchMeasured system was developed. level residences. turer, a portable acoustic data as well as field inspections and

measurements at actual installations helped to clarify the situation and concerns.

Turbine rooftop mount and hoisting apparatus

|32

Turbine lay-down pattern on the space-constrained roof

Collaboration with Southwest Windpower—Manufacturer of the Skystream Marketed to date largely for semi-rural locations, the turbine masts are designed to

f i n A l D E S i g n c o n S i D E R At i o n S

The anticip

Accommodations for mast erection and lowering to en-

under very

able installation regular maintenance inspections Final Designand Considerations

ect structur

needed to be careful coordinated on the already crowded Accommodations for mast erection and building rooftop. A quick sketch study quelled any further lowering to enable installation and regular discussion of masts taller than the 40’ models shown maintenance inspections needed to be above due to space constraints. carefully coordinated on the already crowded

be pivoted into place using a ‘gin pole,’ a

building rooftop. A quick sketch study quelled

cable, and a truck. A different solution was

any further discussion of masts taller than

required to provide maintenance access on

the 40-foot models shown above due to

the building roof, given the difficulty of getting

space constraints. The anticipated reactive

a truck onto the roof. Together with the turbine

forces at the base of the masts under very

manufacturer, a portable manual winch system

high wind speeds were evaluated by the

was developed.

project structural engineer. Due to the seismic

already con

structure pr

loads down

modificatio

The roof sla

mounting p

33|

National Wind Technology Center, Boulder, Colorado

considerations already considered because of the project location, the structure proved robust enough to transfer the turbine loads down to the foundation without any additional modification. The roof slab design, originally developed without the turbines in mind, was modified by adding minor amounts of reinforcement under the turbines and with simple concrete mounting pads to raise the turbine base above the planned green roof soil.

Review and Validation of Work— Visit to the National Wind Technology Center A chance encounter with a past collaborator led to an invitation to present this work to the director and turbine research staff at the National Wind Technology Center. A halfday work session produced suggestions for solving acoustic concerns, ideas for monitoring the wind behavior in order to validate the wind tunnel predictions, and general encouragement for the approach and the endeavor. Notably, the research staff could not find any serious oversight in the research process nor any precaution that would prevent the project from coming to fruition.

|34

Construction process

c o n S t R U c t i o n The turbine masts were hoisted

to the rooftop on the last day before the tower crane was urbine masts were hoisted

dismantled. Thewas crane boom cleared the roof deck by y before the tower crane

22’, roof so hoisting 45’ masts required some degree of com cleared the deck by urbine masts were hoisted ordination. The shop-fabricated steel base tripods have uired some degree of co- Construction y before the tower crane been located on was the cast concrete upstands. Custom-deted steel base tripods haveAs the building neared completion in mid-2009, signed vibration isolation mounts are currently in fabricam cleared the roof deck by crete upstands. tion andCustom-deneed to beproject installed in place of the wood blockuired some degree of costakeholders became increasingly unts are currently in fabricaing seen above before installation can be completed. ted steel base tripods have enthusiastic about the prospect of buildingin place of the wood blockcrete upstands. Custom-deation can be completed. integrated wind turbines on their building. State unts are currently in fabrica-

and Federal agencies who initially politely

in place of the wood block-

turned away inquiries about funding later, ation can be completed. on the basis of this work, invited applications

The turbine masts were hoisted to the rooftop, above lower right, on the last day before the tower crane was dismantled. The crane boom cleared the roof deck by only 22 feet, so hoisting 45-foot masts required some degree of coordination. Shop-fabricated steel base tripods, above left, were installed atop custom-

for funding which resulted in incentives and

designed vibration isolation mounts (replacing

tax credits large enough to offset the cost of

the temporary wood blocking seen in the

construction.

photo).

35|

Photo © Eckert and Eckert

Turbines as installed atop Twelve|West, Portland, Oregon

Conclusion After thirty months of research, design and con-

From an aesthetic perspective the turbines

struction, the wind turbines atop Twelve|West

are a great success. They have become a

began spinning in August of 2009. This event

landmark in the city, an indicator of the mostly

was a milestone and not an end because the

invisible behavior of the wind, and the focus of

team is committed to monitoring the per-

a robust discussion on the scale and production

formance of the wind turbines for five years.

of renewable energy. Perhaps most important

Now that meaningful performance data is

the turbines are a visual demonstration of

available, it is clear that the turbines are not

the potential and also the limited nature of

performing exactly as expected, producing

renewable energy and the corresponding

about sixty percent of the anticipated elec-

need for energy efficiency.

tricity during a twelve-month period in 2010-11. Analysis to explain exactly why is ongoing.

|36

Photo © Timothy Hursley

37|

ROOF TOP

ROOF PARAPET

DOUBLE ROOF

BUILDING FUNNEL

FAÇADE

BUILDING-LANDSCAPE

STRATEGIES OF INTEGRATING WIND TURBINES IN ARCHITECTURE AND THE BUILT ENVIRONMENT 39|

|40

ROOF TOP

Justin Konicek: Museum + Shipyard

This project is situated directly at Erie’s wa-

façade provides information about wind power

terfront. Long view axes through the interior

technology, as well as an explanation and view

spaces and the glass roof characterize the

of the façade’s use of natural ventilation. The

design. Elevated above the workshop, the mu-

rooftop louvers provide ventilation and day-

seum’s display spaces extend via open floors

lighting for the entire interior space.

and skylights throughout the building. Museum attendees on the second floor have an un-

Four vertical-axis wind turbines, mounted hori-

obstructed view to the ground-level dry dock,

zontally on the roof (see section), are visible

and shipbuilding and restoration processes for

through a skylight from the wind exhibition area.

the Brig Niagara. On the third floor, the wind exhibit along the interior of the west double-skin

41|

Site plan

First-floor plan

|42

View from State Street

Section

Preliminary study

43|

|44

ROOF TOP

Elizabeth Jenkins: Under One Roof

As an addition to the existing maritime mu-

This roof is the key element of the addition. Not

seum, this design stresses the connection to

only does it visually connect the new addition

the existing building, while also highlighting the

to the existing museum (see section), but it also

relationship between the rich industrial past of

acts as a funnel for the wind. The sloped struc-

Erie, Pennsylvania, and its current focus on tour-

ture of the roof directs wind upwards toward

ism. These relationships are explored through

the wind turbines at the highest point of the

materiality: brick represents the industrial past

building. Clerestory windows direct an addi-

(including the oldest part of the museum that

tional airflow resulting from natural ventilation

was originally a power plant), while exposed

towards the turbines, which increases the wind

concrete suggests modern times. The museum

velocity and therefore the effectiveness of the

seamlessly connects past and present, leading

devices.

visitors between the two separate elements of industry (ship building) and tourism (the public museum) under a translucent truss roof.

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first floor plan

First-floor plan

|46

Wind Direction

Existing Museum

Transverse section

Preliminary study with vertical-axis wind turbines on the roof

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|48

ROOF PARAPET

William Bunk: Building a Wharf

In this project, visitors are supposed to feel as

The spaces between the trusses at the wind-

if they are visiting an actual, operating wharf

facing parapet act as wind channels. Continu-

on the Erie bayfront. Port elements—including

ing with the modularity, eight vertical-axis wind

docks, dry docks, warehouses, ships, and water

turbines mounted horizontally are incorporated

access points—drive the design of the maritime

between two modules. The torque and shear

museum, which is built around the museum

forces acting on the structure by the turbines

workshop. The result is an industrial, modular

are taken over directly by the massive structural

aesthetic with double-frame trusses spanning

trusses.

the interior workshop and smaller building volumes inserted between them.

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First-floor plan

|50

View from State Street (west elevation) with VAWTs at the parapet

West elevation with eight VAWTs mounted horizontally

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|52

DOUBLE ROOF

Kelly Ryan: Museum as Cloister

The Erie Maritime Museum addition is designed

Six magnetically levitated vertical-axis wind

in the form of a cloister, around a courtyard,

turbines sit at the apex of the restoration

with the big restoration workshop represent-

workshop. Their location is determined by the

ing the sacred space. Situated closest to State

prevailing southwest wind and the importance

Street, the workshop’s pure glass box creates a

of powering the most influential space under-

visible hub of activity throughout the day, and

neath. The key aspect of the turbine integration

casts a beacon of light throughout the night.

is the double roof, which funnels the wind towards the turbines, before creating suction on the back end to increase air velocity (Venturi effect).

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State Street

Site plan

|54

West elevation

Transverse section

View from east

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|56

BUILDING FUNNEL

Marjorie Dona: A Beacon to the City

This museum and workshop design serves as

Two vertical-axis wind turbines are placed on

a “beacon to the city.” Its elongated shape

top of one another at the opening of the glass

directs the local residents to the port and

beacon. The south and south-westerly winds

reconnects the city with Presque Isle Bay. The

funnel through the slanted opening at one end

monolithic structure has a double shell dividing

and exit the building towards the bay. In

the building into three main parts—museum,

addition to serving their purpose of generating

workshop and entertainment spaces—that are

wind energy, the turbines become part of the

represented primarily by glass, aluminum, and

wind exhibition­—viewed by visitors through the

concrete. Through its use of aluminum clad-

glass façade.

ding and louvers, the façade gives a ghost-like view of the Brig Niagara housed within a water basin.

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Section

First-floor plan

|58

59|

|60

BUILDING FUNNEL

Kara Knechtel: Erosion

This design tells a story of the dynamic interac-

along this grid. By funneling the wind through

tion between a building and its environment:

the building, its velocity—and its potential for

how wind forces might affect a building shape,

harvesting wind energy—is increased. Different

facade, and interior layout, and how a building

wind turbine products are arranged in the hole

affects the wind.

to generate energy and showcase how wind energy can be utilized. The main circulation

The building shape was informed by the city

spaces are positioned at this hole to corre-

structure, as well as the wind patterns of the

spond with the wind’s path. Gill-like windows

site. The tectonic, rectilinear shape fits in the

in the building funnel allow for natural cross

grid layout of Erie, and the subtractive voids

ventilation through the open floor plan.

react to the diagonal direction of the wind

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Second-floor plan

Diagonal section

|62

Main directions on site

Site plan

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|64

FACADE INTEGRATION

Kyle Schillaci: Coal-esce

The Erie waterfront boasts strong historical

Environmental considerations reduce the

ties to both maritime and industrial pastimes.

building’s energy consumption. The building

Population growth and societal changes over

utilizes recycled steel for the primary and sec-

time, however, have changed the waterfront

ondary structure. The exterior steel mesh and

into a tourist attraction and teaching experi-

double façade allow for natural lighting and

ence for local children. The project proposes

ventilation. Additional shading is applied with

to reconnect the local residents to the water-

photovoltaic louvers, which also allow for ener-

front through an elevated railway surrounding

gy generation. A twenty-foot diameter horizon-

the waterfront district. A tower evoking the

tal-axis wind turbine is located at the structure’s

character of a ship and sail serves as a coun-

peak, enabling maximum wind exposure

terbalance to the horizontality of the railway

channeled into the turbine via an adjacent

and existing urban grid. The wind direction and

shear wall. The “turbine crown” is a highly

dynamics are expressed in the undulating floor

visible statement of embracing the aesthetics

plates and façade.

of sustainable technology.

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Section of workshop and exhibit spaces, structure and horizontal-axis wind turbine

|66

Site plan

View from Presque Isle Bay (south-east)

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|68

BUILDING LANDSCAPE INTERACTION

Ryan Orr: Inundated Haven

The project creates an environment to connect

haven. Six horizontal-axis wind turbines stand

with wind and water, with an overall goal of

on high masts in the water. The turbines and the

appreciating Lake Erie from various perspec-

water level create two horizontal layers with a

tives. It aims to give people access to the water

well-defined, void space in between that is oc-

while studying the wind qualities at the site.

cupied by “building piers.” These “piers” are ori-

This was accomplished through the aesthetics

ented to the optimum sailing position, and the

of a pier-like mooring. Parts of the land area

wind turbines are positioned to most effectively

were removed to allow for an expansion of the

capture the strongest and most frequent winds.

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Site plan

View from State Street

|70

Main wind frequency

Main wind energy

Elevation

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|72

BUILDING LANDSCAPE INTERACTION

Michael Stonikinis: Layers of History

The Erie waterfront is a unique site with a proud

smokestack. Once part of a large coal power

maritime history that can be traced well into

plant in the early twentieth century, the Erie

the eighteenth century. Historical evidence is

smokestack was left intact after the plant’s

few and far between, as many of the fisheries

demolition. Currently, it stands in a large field

and industrial hubs that once existed on the

—without context or a purpose. A wind turbine

site have disappeared. This project attempts to

system placed on the smokestack repurposes

integrate wind energy into the nearby environ-

the rare icon within a new context. This strategy

ment to interact with the site’s precious rem-

of utilizing elements from different periods was

nant history. Perhaps the most notable icon of

used throughout the project to form a new

Erie’s maritime-industrial past is the waterfront’s

whole.

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First-floor plan

|74

Section showing wind harvesting (cross ventilation, wind turbines)

View from Presque Isle Bay

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|76

BUILDING LANDSCAPE INTERACTION

Marc Pelletier: Grides + Nodes

ROOF TOP

This project is an interpretation of Erie’s city grid

concept of the grid allows a fluid circulation

and its expansion toward the bayfront and into

path while highlighting nodes along the path

the museum. Key intersection points of the grid

by displaying the structure at these key points.

lines—the nodes—are occupied by vertical circulation elements. This three-dimensional grid

Wind power was incorporated by placing verti-

offers visitors of the bayfront and the museum

cal-axis wind turbines at the top of the structural

the opportunity to start and end at the same

nodes as well as doubling the parking lot lights

point without ever retracing their path. The

with horizontal-axis wind turbines.

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Site plan with first floor

|78

Section

Elevation from State Street

Elevation from Presque Isle Bay

Section model

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|80

BUILDING LANDSCAPE INTERACTION

Aaron Wertman: Bayfront Heritage Garden Center

DOUBLE ROOF

The museum and workshops provide educa-

In addition to the airfoil turbines, the project

tional experiences for the general public and

implements standing, horizontal-axis turbines

students, exposing them to the rich maritime

in a water treatment park in front of the struc-

cultures across the bayfront. The main workshop

ture. The gray-water and black-water treat-

space boasts a large airfoil that utilizes the Ven-

ment system treats water from both the new

turi effect. Air velocity increases as wind flows

building and the existing maritime museum.

through the dense space between the arched

The standing wind turbines power the pumps

roof and the airfoil. The roof shape creates a

that move the water throughout the system,

negative air pressure at the leeward side thus

from the buildings to the wetlands and from the

drawing additional air through the roof. Air will

collecting pools back to the mechanical rooms

be pulled from adjacent spaces in the build-

for redistribution. As one of the most prominent

ing and directed through vents at the highest

features of the landscape, these turbines also

point of the arched roof, where it helps turn the

serve as icons, educating the public on sustain-

turbines.

able wind power technologies.

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Site plan with first floor

|82

Section showing cross ventilation and wind turbines in double roof

Cross section

Elevation from Presque Isle Bay

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This publication accompanies the exhibition Wind Turbine Integration in Architecture and the Urban Environment, presented at the Willard G. Rouse III Gallery, Pennsylvania State University, University Park, PA, August 22 - October 7, 2011, and the Erie Maritime Museum, Erie, PA, April 14 October 12, 2012. The publication and exhibition were generously supported by the Stuckeman Collaborative Design Research Fund, the Penn State Institutes of Energy and the Environment (PSIEE) Sustainability Seed Grant Program, and the Raymond A. Bowers Program for Excellence in Design and Construction of the Built Environment.

All rights reserved. © of the edition, The Pennsylvania State University Ute Poerschke, Associate Professor, Department of Architecture © of the texts, their authors © of the images, see list below Image Credits: The Pennsylvania State University: cover, content page, pages 2-15 and 39-83. Eckert and Eckert: page 36. Timothy Hursley: pages 18, 37. ZGF Architects: pages 21-35. This publication is available in alternative media on request. The Pennsylvania State University is committed to the policy that all persons shall have equal access to programs, facilities, admission, and employment without regard to personal characteristics not related to ability, performance, or qualifications as determined by University policy or by state or federal authorities. It is the policy of the University to maintain an academic and work environment free of discrimination, including harassment. The Pennsylvania State University prohibits discrimination against any person because of age, ancestry, color, disability or handicap, national origin, race, religious creed, sex, sexual orientation, gender identity or veteran status. Discrimination or harassment against faculty, staff or students will not be tolerated at The Pennsylvania State University. Direct all inquiries regarding the nondiscrimination policy to the Affirmative Action Director, The Pennsylvania State University, 328 Boucke Building, University Park PA 16802-5901;tel.(814) 865-4700/V, (814) 863-1150/TTY. U.Ed. ARC 12-42.

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ISBN 978-0-615-54244-7