recent energy trends in energy policies: clean and ...

ENTECH’15 III. Energy Technologies Conference 21-22 December 2015, Istanbul, Turkey

RECENT ENERGY TRENDS IN ENERGY POLICIES: CLEAN AND RENEWABLE ENERGIES MURAT AKCIN, CEMAL KELES, ASIM KAYGUSUZ, ABDULKERIM KARABIBER, BARIS BAYKANT ALAGOZ Murat Akcin, Inonu University, Electrical&Electronics Engineering, Malatya, Turkey Cemal Keles, Inonu University, Electrical&Electronics Engineering , Malatya, Turkey Asim Kaygusuz, Inonu University, Electrical&Electronics Engineering , Malatya, Turkey Abdulkerim Karabiber, Bingol University, Electrical&Electronics Engineering , Bingol, Turkey Baris Baykant Alagoz, Inonu University, Electrical&Electronics Engineering, Malatya, Turkey Abstract As an indicator of sustainable development, renewable and clean energy policies are becoming a major concern in the agendas of scientific and political authorities. In today’s world, energy and information technologies are indispensable for the development of nations, and reliability of energy source and management of information turn into a top security issue. As the reflection of desire to own energy, countries have been in competition to dominate energy sources in history. Governments organize their energy policies to ensure energy security of countries, however, the primary goals in energy policies should be cheaper, reliable and eco-friendly energy utilization. Due to the increasing energy demand and diminishing fossil fuels, studies on electrical energy production with renewable sources such as hydraulic, solar, wind, biomass and geothermal promise opportunities to build a habitable world. Today, electrical energy production has been mainly derived from limited sources, particularly from coal and natural gas reserves. However, coal and oil reserves in the world are finite and it is known that it will diminish in the near future. Hence, energy policies must take into account renewable sources, which are principally eco-friendly and easy-accessible. This study highlights recent trends in renewable energy resources. The clean energy policies and solutions to increase renewable energy penetration are discussed. Introduction There has been a significant increase in electrical energy demand with economical and technological developments due to the fast-growing population all over the world. Generating electricity from renewable energy sources has a major significance in the energy policy strategies on a global scale (Benli, 2013). The developed countries of 21th century began to increase clean and renewable energy utilization, mostly based on wind and solar energy and made serious investments for the research of these resources. Due to increasing importance of energy strategies, unfortunately, words of energy, war and strategy are used together in politics in the last century. It is a reality that there is intensive political struggle around diminishing energy resources. Countries, which retain the control of the energy resources, have given direction to world energy policies in the 21th century (Iskender). But, we believe that increasing use of distributed renewable energy sources can be a solution for 8


conflicts caused from aggressive energy politics as well as environmental constrains concerning with a clean and sustainable energy harvesting from natural sources. The energy policies of countries take into account the following factors in their energy investments: energy security, climate conditions, environmental motivations, industrial and economic development, financial risks and profits, generation stability, generation flexibility and energy continuity. Although ongoing investments for conventional energy resources based on fossil fuels still slow the spread of sustainable and smart electricity services based on renewable energy resources, the diminishing fossil fuel resources and increase of oil price in international markets make a pressure on industrial and academic authorities to focus their interest on the renewable energy utilization and required technologies for electricity generation. Hence, core of smart grid prospect resides on distributed renewable generation and integration applications. However, there is a need for supportive regulations for encouragement of renewable energy utilization and for reduction in the initial investment cost of renewable energy sources, because these two strategies will play an important role in rapid proliferation of renewable energy utilization and technologies (Fouquet, 2013). Renewable energy sources is more clean, sustainable, and eco-friendly compared to the other energy sources, and the environmental risks of these sources such as carbon emission is almost zero. On account of these advantages, renewable energy sources must become the primary source for the energy demand in the long run. Actually, the future of renewable energy is not a choice. Indeed, it is an inevitable trend pushed by technological development, economic and political obligations, and environmental constraints (REN21, 2013). Figure 1 illustrates energy demand estimations from different resources between 19872011 and 2011-2035 years. The figure demonstrates that the primary energy demand is mostly provided from fossil based fuels between 1987-2011. On the other hand, from 2011 to 2035, it is expected that the renewable energy demand will present the highest rise in energy demand and this is an indicator for the upcoming trend of renewable energy utilization. Figure 1 also reveals that demands for nuclear energy will increase so that it has advantages of high power rate and stable generation potential, which is a requirement in industrial countries.

Figure 1. The growth of total demand for popular energy sources (World Energy Outlook 2013) Increasing the energy demand along with technological growth has brought environmental problems. The increasing energy demand from the conventional energy sources such as coal and oil causes the serious environmental pollution (Bollen, 2010). Today,

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the access of clean natural resources is more substantial for life. Therefore, life cycle emerged between these trios: energy, water and environment. This challenging situation can be summarized as "more energy, less carbon dioxide" (Shell International BV). This study highlights the recent renewable energy solutions and their importance for the clean and efficient energy policies. Also, a brief discussion on the contribution of smart grid technologies to renewable energy penetration is given in the further sections. Clean and Sustainable Generation: Renewable Energy Sources Energy is an important concern for sustainable development and leading to significant environmental pressures visible at the global, national and local levels (Stigka, 2014, del Rio, 2009). Many study reports that clean and sustainable development can be possible by increasing renewable energy utilization rates in the energy demand. Electrical energy generation is based on a variety of energy sources including mineral fuels, oil, gas, nuclear power and renewable energy sources in many countries (Reuter, 2012). The renewable energy sources offer great potential for sustainability and they are emerging as technically feasible, economically viable and socially acceptable alternatives among energy sources possibilities (Mourelatos, 1998). Renewable energy is commonly defined as the energy obtained by ongoing natural processes. Nowadays, the renewable energy is popularly harvested from the natural energy flows such as sunlight, wind, rain, hydropower, waves and geothermal heat (Renewable energy, 2015). By regarding the formation process, fossil fuels may be considerable as renewable energy. But these sources have come to point of exhaustion as a result of extensive utilization and renewability property of the fossil fuels is extremely low due to requirements of millions years under extreme heat and pressure conditions for the oil generation in nature. On the other hand, CO2 emission and environmental impacts of fossil fuels are severe. Therefore these sources could not be located within a category of renewable energy sources. The popular renewable energy sources are briefly explained in the following sections. Solar Energy Solar power plays a major role in the solution for the energy crisis in the near future (Tahri, 2013). Depending on the lifetime of sun, the solar energy is reliable, infinite and free. In addition, there is a widespread research activity in academy and industry in order to reduce installation and operating cost while increasing energy conversion efficiency of solar energy systems (Tahri, 2013). In recent years, photovoltaic market experiences a significant growth not only in rural but also in urban areas all over the world (Kaldellis, 2010). While the first silicon solar cell was developed with efficiency of 6%, today, the efficiency has been reached 30% (El Chaara, 2011). The solar energy can be utilized in many ways from heat to light energy. A number of the technologies based on biotechnologies (biofuel from crops, oil seeds, microalgaes (Mata, 2010)), thermal methods (solar power tower, solar thermal plants) and solid-state based methods (photovoltaic panels) have been in development for several decades. The contemporary solar energy systems finding widespread usage all over the world can be grouped as follows: Heating systems with solar energy, planar solar collectors, concentrating solar power plants, solar furnace, solar chimneys, solar ponds, photovoltaic systems. As a major source of renewable energy, the portion of solar energy in electricity generation goes into increasing trend in total renewable energy demand due to the advance

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in solar technologies and the decrease in reserves of conventional energy sources. In recent years, the efficiency of solar modules has been improved significantly, and now reaches 40% by the use of new technologies (Green, 2012). Besides the photovoltaic technologies, solar thermal technologies such as power tower and high-temperature parabolic collectors make possible high power generation capacity over hundreds megawatts (Solar power plants in the Mojave Desert). Figure 2 depicts high power solar plants implemented over hundreds megawatt.

Figure 2. High power solar plants in the world (Left image: solar thermal plants with hightemperature parabolic collectors, Middle image: solar power tower, Right image: solar photovoltaic power plants) (Wikipedia) Wind Energy Wind energy is indeed kinetic energy of air flows. Wind power is the transformation of wind energy to a useful energy form by wind energy conversion systems such as wind turbines generating electrical power as in Figure 3, windmills providing mechanical energy, wind pump used for pumping water or drainage or sails to boost vessel. Theoretically, wind power is proportional to the third power of the wind speed. In other words, the wind force increases cubically with increasing a unit in wind speed until a saturation level (Wind energy, 2015). The region exhibiting constant wind regimes makes wind energy generation reliable and efficient.

Figure 3. Wind turbines from the world (Left image: Offshore wind farm, Middle image modern low-wind turbine, Right image: vertical axis wind turbine) (Wikipedia)

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Increasing energy demand and reduction of fuel resources are enforcing energy community to produce electricity in a sustainable way from preferably wind energy. Because, zero-emission renewable energy systems such as wind turbines and solar cells are also declared a key factor in reducing global climate change in the future. It was widely accepted that one of the clean and renewable ways of energy harvesting is the wind energy, which is most cost-effective and the world’s fastest growing energy sources (Benli, 2013). Among the renewable energy sources, especially the wind energy has achieved market development, and experienced the greatest growth worldwide (Yue, 2001). In the last decade, a sharp rise in wind power generation confirms worldwide growing of wind energy market. However, there are many countries that have not established specific policies on wind energy, yet. This means that potentials of wind energy have not yet been fully explored by all countries in the globe (IEA, 2006). Nonetheless, many developed countries have established incentive policies to increase wind energy for electricity generation. Some of the success stories have come from wind energy utilization in USA, Canada, Denmark, Germany, Turkey, Australia, China, Japan, and South Korea. For these countries, strong wind energy policies and supports are managed to increase wind power generation significantly (Saidur, 2010). Hydropower Energy The renewable energy sources are preferred to be consistent, domestic, clean, controllable and it is very advantageous if allows deferrals in generation. In this respect, hydropower is already the most important renewable and widely utilized renewable energy source. Consequently, hydropower contributes one-fifth of the power generation of the world (Capik, 2012). The speed of the water flow or fall of water determines the running water force. The hydropower plants (HPP), which established on the purpose of converting the running water force into electricity, produces the high amount of energy from water flowing from a higher water reservoir to a lower point (What is the hydroelectricity power, 2015). According to storage structures, hydropower plants are divided into three groups: With Storage (Reservoir) HPP, River Type (Regulator) HPP, Pumped Storage HPP. Today, due to the growing concern for CO2 emissions and increased demand for energy, hydropower plays a substantial role in renewable energy policies of the countries as an integral part of water management strategies. The other significant benefits of hydropower are the control flooding, regulation of water supplies, increase of air quality and living conditions. As a consequence, it contributes to clean water storing, reducing greenhouse gas, irrigation lands and climates and reducing soil erosion. The main disadvantage of hydropower is relatively high initial capital costs (Capik, 2012) and the negative effect of hydropower stations construction on living conditional of endemic species. Biomass Energy Biomass, which requires any organic matter derived from living organisms, is one of the sources for renewable energy generation (Mafakheri, 2014). As seen in Figure 4, it is involved of plant and animal materials, as well as residues such as wood from forests, crops, seaweed, materials left over from agricultural and forestry processes, and organic industrial, human and animal wastes (Saidur, 2011). The biomass energy is not intermittent energy sources such as wind and solar energy. As long as the sun is in existence, the biomass energy stores the carbon by means of photosynthesis. In fact, biomass technologies can be considered as a biological method for harvesting solar energy. Today, growing industrial crops for the energy proposes is becoming popular as an alternative for fossil fuels, but the total amount of energy

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from industrial crops is too low compared to the volume of fossil fuel production. Municipal Solid Waste (MSW) is a source of biomass and amount of energy obtained from waste (EfW) depends on human population and compounds of waste materials. As part of waste management system, EfW plants can generate electricity from the MSW and provides waste disposal with minimal environmental impacts (Baran, 2013). The most common biomass to energy conversion methods are: direct combustion, pyrolysis, fermentation, gasification, and anaerobic digestion. The choice of the method depends on a number of factors, such as the type and amount of biomass, environmental standards and economic issues (Saidur, 2011).

Figure 4. Sources for biomass (Biomass Sources, 2014) Geothermal Energy Geothermal energy consists of the thermal energy stored in the Earth's crust (Abbas, 2014). Geothermal energy comes from any kind of geothermal sources directly or indirectly. The geothermal energy is also clean, sustainable, inexhaustible and independent from meteorological events and it can be used either for power generation or for heating depending mainly on location and temperature of geothermal sources. Mainly, high o temperature geothermal resources above 150 C can be used for power generation. Whereas, o o o moderate temperature between 90 C and 150 C, and low temperature below 90 C resources are appropriate for direct applications such as heating, cooling, aquaculture, and fish farming (Guo, 2011). Figure 5 demonstrates the components of an integrated geothermal energy source. Although confirmed advantages of local geothermal energy production, the future of geothermal energy is dependent on energy prices and technical developments in geothermal energy technology (Abbas, 2014).

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Figure 5. Integrated geothermal energy utilization process (What is the geothermal energy, 2015) Wave, Tidal and Current Energy Seas and oceans are also source of renewable energy. The marine-based renewable energies are listed as follows (Orer, 2003): wave energy, tidal current energy, sea temperature gradient energy, sea salinity gradient energy, sea current energy, surface evaporation energy. Wave power is determined by wave height, wave motion, wavelength, and water density. As for that, the wave height depends on wind speed, time of wind blowing, the distance of wind blowing from water, and depth of the water. In general, the large scale of wave has a higher potential energy (Energy from the oceans, 2015). The providing of electrical energy from ocean waves has been largely investigated and many technologies have been tested (Boake, 2002). The wave power concept developed by Uppsala University is a solution that aims to contribute to the energy supply with a robust and economically competitive system (Castellucci , 2013). Tidal is one of the clean energy sources that allow a finite amount of daily supply at certain tidal times. Tidal current generator and tidal barrage utilize kinetic energy and potential energy from tidal force. Hopefully, the capital and operational costs of emerging technologies may fall in future. Tidal current energy generation is an immature stage today and however new generation technologies should aim to make significant reductions for the both capital and operating costs. This provides the ability for tidal power to produce electricity at a cost comparable to wind of open sea (Johnstone, 2013). Permanent ocean and sea currents are also used for energy harvesting in a similar manner to winds that is flow of air. Since current turbines can be installed under the water, they do not disturb life and activities on the surface. Energy Policy and Renewable Energy One of the problems slowing down renewable energy penetration is that the top agenda of energy policies has been largely occupied by classical energy security issues. It is agreeable that energy is indispensable for humanity and the development of countries. Availability of energy resources, easy accessibility and durability are among the significant topics of the classical energy security policy for nationals and international plans. The energy security was 14


classically defined as a physical protection of energy exploration, development, transmission, conversion, distribution, marketing and consumption processes against any kind of attack. However, energy security must be also cover topics of consumption efficiency, economical costs, energy source diversity and environmental constraints such as efficient, clean and sustainable generation. Because, it is obvious that future of humanity depends on preservation of natural resources and ecological balances of earth and living in eco-friendly ways without breaking life chains. Therefore, modern energy policies must complete the energy security via increasing the diversity of renewable energy sources. With fast growing industrialization, the increase in use of energy has brought severe ecological problems. Due to the excessive use of fossil fuels, harmful greenhouse emissions give the signals of global warming, drought and natural disasters directly. In addition, it causes deterioration of the ecological balance because of the reducing the quality of climate conditions for life. The contemporary energy security agendas suggest that all countries must design their energy policies with clean, sustainable and inexhaustible energy sources. The use of renewable energy sources gains an increasing importance day by day as exhaustion of natural resources and environmental pollutions become more apparent. Innovative technologies and novel developments increasing the efficiency and flexibility of existing grid address problems of reliability in energy generation and distribution, fulfilling the energy demand and increasing the number of renewable energy sources. Smart Grid technology is name of these next generation grid technologies. It is designed for higher efficiency and reliability, lower carbon emission in addition to fulfilling the optimal balance between energy demand and generation.

Figure 6. The integration domestic source for buildings (REN21, 2013) The distributed renewable energy integration will be possible by widespread use of domestic renewable energy systems in buildings. Domestic applications benefiting from

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various renewable energy resources were developed for smart grid era. An application model for smart house is shown in Figure 6. In order to generalize the use of renewable energy, some policies and sanctions can be applicable. We list some of them as follows: - Legally binding targets should be placed for renewable energy, - Electricity market should be regulated for distributed electricity production and combined heat and power (CHP) systems should be considered in energy applications. - Support mechanism should be placed for research, development and commercialization efforts, - The guarantee of purchase of electricity generated from renewable sources, quota systems and financial supports should be made more attractive, - Energy efficiency standards must be brought for equipment, vehicles and all materials, - Carbon trading should be developed, - Subsidies should be reduced for fossil fuels and nuclear power plants, - Industrial policies focusing on renewable energy targets should be developed in terms of international competition and labor, - The energy infrastructure should be formed taking into account not only economical costs but also the social and environmental costs. - At the same time, legal arrangements and standards should be developed for supporting renewable energy based power generation for "on-site production, on-site consumption". - Smart meters and demand side load management tools should be used in buildings and intelligent power management systems should be encouraged. - Regulations for building isolation and reduced carbon emission should be applied. Smart Grid Applications and Renewable Energy Utilization Recent studies on smart grid studies are focused on three fundamental concepts: Distributed generation (DG), Distributed storage (DS) and Demand side load management (DSLM) (Alagoz, 2012). Figure 7 summarizes developments provided by smart grid technology. Firstly, these developments make possible intermittent renewable energy source integration into electricity grid. DG and DS applications facilitate penetration of renewable energy into grid and support renewable generation from large scale (hundreds Megawatts) to domestic scale (a few kilowatts). Essentially, DS allows deferral of utilization of generated redundant renewable energy to inefficient hours of renewable generation. DSLM provides demand elasticity and it makes electricity grid more flexible (Finn, 2010). Today, the most widely used renewable energy sources are solar and wind energies, which have disadvantages of dependence on methodological conditions (Yumurtaci, 2013). The demand elasticity enables to adaptation of power consumption according to fluctuating solar and wind energy generation conditions and supports proliferation of these sources in electricity grid.

Smart Grid

DG

Renewable Energy Utilization

DS

Demand Elasticity

Energy Efficiency

DSLM

Figure 7. Smart grid applications and opportunities

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As smart grid technologies find implication in distribution, trends in distributed renewable generation will be strengthened and, in the recent future, solar and wind generation in domestic level will be more prevalent. As energy generation takes place at domestic level and the smart grid increases generation scalability and diversity. Generation scalability and diversity enhance self-healing skills of electricity grid and makes the system more reliable in term of energy supplement. Smart grid technologies support demand elasticity, generation diversity and scalability, grid flexibility, energy efficiency and reliability. Figure 8 presents flow chart illustrating topics related smart grid technologies. All these topics should be included in modern energy security policies and there is need for revision of classical energy policies in global scale.

Figure 8. Smart grid, renewable energy and carbon reduction relation Conclusions It is foreseen that smart grid application facilities distributed renewable energy utilization even in domestic level. This development opens doors in the way of micro-balance in energy, where consumers can generate and share energy to meet their own and perhaps their neighbor demands by renewable energy. These grid users are referred as “prosumers” in previous studies (Grijalva, 2011). These fundamental transformations in energy grid may have reflections on macro energy politics and it supports “liberalization” or “civilization” of energy generation and sharing tasks. On the other hand, globalization trends of world can remove national borders in energy maps and thus energy dispatching in global scale becomes more regular and independent of arguments of national politics. During this transformation taken place in the smart grid era, the renewable energy policy should be always placed at the top of the agenda. Because, energy efficiency, conformation to environmental constraints, diversity, sustainability and scalability of generation can be possible by increasing renewable energy utilization. Governmental supports and funds are required for the proliferation of domestic renewable generation. A recent effect of domestic renewable generation will decrease yearly growth of fossil fuel energy generation and therefore it becomes a permanent solution for the fundamental problems of energy community year by year. With consideration of resources, financial and climatic issues; the debate of renewable energy should keep up to date all over the world. A global awareness for clean and renewable

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