Role of hydrogen in the renewable energy sector

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applications of the alternative energy systems. Renewable. Energy sources will reduce our national dependence on foreign oil and enhance our homeland ...
3 rd Internatio na l G radu ate Conferen ce on Engineering, Science and Humanities (IGCESH) School o f Gradu ate Studies Universiti Tekn ologi Malaysia 2– 4 November 2010

Role of hydrogen in the renewable energy sector Ali Mohammad Dastgheib, Hadi Nabipour Afrouzi Dept of Electrical Engineering University Teknology Malaysia (UTM)

Johor,Malaysia [email protected] [email protected] Abstract— as the price of oil and natural gas continues to

Hydrogen not only can be produced with ‘‘zero

increase, reaching levels that threaten our local and national Economy, the need to seek alternative sources of energy has become necessary to reduce our dependence on foreign oil and enhance homeland security. The renewable energies such as solar, wind, hydro and biofuels that need to be explored for generating hydrogen as an energy carrier. Engineering and Technology graduates must be well educated and highly trained with use and applications of the alternative energy systems. Renewable Energy sources will reduce our national dependence on foreign oil and enhance our homeland security because of their environmental and economical merits .

emissions’’ from fossil fuels, but also can be come by from several sources. Production from fossil fuels could be considered as a ‘‘technological bridge’’ towards new processes like biological and ‘‘new’’ nuclear, photo electrochemical, biological and ‘‘new’’ nuclear, expected for the second-half of the century. Actually, the development of technologies for distribution and consumption of hydrogen will be the basis for the introduction of those CO2-free production technologies

[9].

Hydrogen is an energy carrier and must be produced from another substance. It is not widely used today but it has great potential as an energy carrier in the future [3]. Large quantities of hydrogen can be easily stored in order to be used in the future, and it can store the energy until it’s needed and can be moved to where it’s needed. Hydrogen can also be used where it’s hard to use electricity. It can be a big player of energy role and become a widely used alternative to gasoline, just many new facilities and systems must be built. We will need economical fuel cells to facilitate make hydrogen, store it, and move it. We can make it and consumers will need the technology and the education to safely use it [7].

In this paper we describe about hydrogen fuel , role of hydrogen in the renewable energy sector , the requirement in establishing the hydrogen as alternative fuel prospect of it as the future in the world . Hydrogen most of the time use for storage and it can be a clean energy in the future. Keywords-hydrogen, cell,economcy

renewble

I.

and

sustainable

fuel

I NT RODUCT ION

Hydrogen is the simplest element that human known, it means each atom of it has only one proton. Hydrogen is the lightest, the simplest, and one of the most plentiful elements in nature [9]. It is represented by the symbol H. The sun is a giant ball of hydrogen and helium gases. Pure hydrogen does not have an odor, color and taste . It always combined with other elements and has variety good properties . The two main uses of hydrogen are in fossil fuel processing and ammonia production mostly for the fe rtilizer market.

II.

HYDROGEN AS AN ALTERN ATIVE AND RENEWABLE F UEL

Hydrogen and fuel cells is a new and different energy system. With water as the only emission Hydrogen can be converted to energy in fuel cells. It is produced from water using renewable energy sources. This energy system therefore holds the potential of zero emission [15] [5].

Hydrogen also produced from the electrolysis of All energy comes from renewable energy sources like wind, solar, hydro, waves, and biomass. The energy is used directly or stored in hydrogen for use in transportation or to create electricity whe re the sun is not shinning or the wind is not blowing. The renewable energy is stored in hydrogen by splitting water into hydrogen and oxygen to produce electricity that called electrolysis. Other productions methods will also be used to create hydrogen from fossil fuels [3].After the production of hydrogen functions. A fuel cell is used to convert the hydrogen into energy again. In the fuel cell hydrogen and oxygen (air) reacts and creates water as the

water or other hydrogen production methods [7]. However, there are many barriers on the large -scale production of hydrogen as a clean and renewable fuel, in order to be a supplement or replacement fossil fuel . Today Most of our energy comes from sun's radiant energy. Hydrogen gas is lighter than air therefore, it rises in the atmosphere. This is why hydrogen as a gas (H2) is not found in pure on earth. It is found only in compound form with other elements [1].

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3 rd Internatio na l G radu ate Conferen ce on Engineering, Science and Humanities (IGCESH) School o f Gradu ate Studies Universiti Tekn ologi Malaysia 2– 4 November 2010

dealkylation, hydride sulfurization, and hydro cracking, all methods of refining oil for wider use. Hydrogen is also used to produce methanol and hydrochloric acid, as wel as being used as a reducing agent for metal ores. Hydrogen is used as a shielding gas for welding, isolating the site of the w eld from atmospheric gases . It is used for cooling rotors in electrical power generators because of its high thermal conductivity.

only emission. The reaction creates electricity and heat that can be used in various applications [7]. Commercially, hydrogen is mainly produced from fossil fuel and in lesser extent produced by electrolysis. Hydrogen is an alternative fuel for two reasons: although hydrogen offers many benefits, there are two drawbacks to using it as a fuel with current technology. Liquid hydrogen is the best form o f hydrogen; it requires four times the storage space of normal petroleum-based fuels. The other problem is that producing hydrogen depends on the availability of a nonrenewable resource, for industrial use hydrogen is produced from raw petroleum, but petroleum supplies may become limited in the near future [3]. Energy storage using liquid nitrogen/liquid air involves the production of the cryogen through an air separation and liquefaction process. Then the cryogen is transported to end-users where it is heated by using the environment heat or heat from renewable resources (e.g., solar) and if available generate electricity by using a cryogenic heat engine . As a renewable energy carrier, cryogen can also provide dir ct cooling and refrigeration, air conditioning units and a t as power source for vehicles and ships [3][12][13].

Liquid hydrogen (LH2 or LH 2) is the liquid state of the element hydrogen. Hydrogen is found in the molecular H2 form. In most rocket engines fueled by liquid hydrogen, it first cools the nozzle and other parts before being mixed w ith the oxidizer (usually liquid oxygen (LOX)) and burned to produce water with traces of ozone and hydrogen peroxide. Practical H2/O2 rocket engines run fuel -rich so that the exhaust contains some unburned hydrogen Liquid hydrogen can be used as the fuel storage in an internal combustion engine or fuel cell. Various submarines and concept hydrogen vehicles have been built using this form of hydrogen. Since neutrons and hydrogen nuclei have similar masses liquid, hydrogen is also used to cool neutrons to be used in neutron scattering, kinetic energy exchange per interaction is maximum.

Hydrogen is a good candidate for a fuel because of its physical and chemical properties. At normal conditions, hydrogen is a colorless and odorless gas. It is stable and coexists harmlessly with free oxygen until an input of energy drives the exothermic (heat releasing) reaction that forms water. A fuel cell is an electrochemical engine hat converts the chemical energy in hydrogen molecule into electrical energy. Hydrogen reacts with oxygen to produce electricity in a fuel cell. In order to make hydrogen as a renewable fuel it should use renewable energy, such as wind power or sol hydrogen produced. Wind power is a renewable energy source with no greenhouse gas emissions, but has problems in integrating with national grids. Combination of wind and hydrogen can be contradict with their inherent defects and be an effective tool in the battle against warmonger power, for production. Hydrogen is ideal as an alternative fuel, producing little or no emissions, with a huge supply available. But hydrogen produced by standard means is not renewable or carbon neutral. Wind power is a totally renewable energy source with no greenhouse gas emissions, but due to its unpredictability, has problems integrating w ith national grids. Combination of wind and hydrogen can contradict with their inherent defects and be an effective tool in the battle against carbon dioxide and

Hydrogen's isotopes Tritium, is used as a radiation source in luminous paints and is a component of hydrog bombs. Another isotope, especially deuterium, is used in nuclear reactors. Deuterium can be used as a neutron moderator for fission reactions, or a fuel for fusion reactions. Bio fuels and hydrogen have characteristics that are beneficial in principle. Their use is useful in compared to fossil fuels: - Bio fuels and hydrogen may reduce the external energy dependence. They could be produced domestically in the EU, improving domestic energy security, reducing petroleum imports, and reducing the reliance on petroleum from unstable areas of the world. - Bio fuels and hydrogen may help to stabilize fossil fuel prices. Petroleum prices are unstable and expected to increase over time. However, bio fuels are a backstop technology, potentially constraining the growth in petroleum prices. - Bio fuels and hydrogen may help to reduce the emission of Greenhouse gases (GHG) and other emissions. Bio fuels recycle carbon from the atmosphere and have cleaner missions, thus reducing GHG emissions and mitigating climate change. - Bio fuels may be an additional source of income for the primary sector. Bio fuels are renewable and increase the demand for agricultural commodities, thus potentially boosting agricultural producers’ income and prices [1] [8]

global warming [1]. III.

HYDROGEN US ES

Hydrogen is used in massive quantities in the petroleum and chemical industries. In the food industry, hydrogen is used to hydrogenate oils or fats that permit the production of margarine from liquid vegetable oil. In a petrochemical plant, hydrogen is used for hydro

[9].

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3 rd Internatio na l G radu ate Conferen ce on Engineering, Science and Humanities (IGCESH) School o f Gradu ate Studies Universiti Tekn ologi Malaysia 2– 4 November 2010

IV.

HYDROGEN ENERGY

appropriate storage space, such systems could store energy even on a cyclic basis.

Hydrogen is high in energy, until now an engine that burns pure hydrogen produces almost has no pollution. A fuel cell combines hydrogen and oxygen to produce electricity, heat, and water. Fuel cells are o ten compared to batteries. Both convert the energy produced by a chemical reaction into usable electric power. However, the fuel cell will produce electricity as long as fuel (hydrogen) is supplied, never losing its charge. el cells are a promising technology for use as a source of heat and electricity for buildings, and as an electric l power source for electric motors propelling vehicles. el cells operate best on pure hydrogen. But fuels like natural gas, methanol, or even gasoline can be reformed to produce the hydrogen required for fuel cells. Some fuel cells even can be fueled directly with methanol, without using a reformer. In figure 1 show a hydrogen fuel cell [2] [17].

Batteries alone are not appropriate for long-term energy storage because of their low energy density and leakage. The combination of a battery bank with long-term energy storage in the form of H2 can considerably improve the performance of standalone RE systems. Also, the overall RE system performance is very sensitive to local weather conditions. In consequence, to achieve an adequate performance from such a complex system, one requires appropriate components and a welldesigned control system in order to achieve autonomous operation and energy management in the system [7]. In the future, hydrogen could also join electricity as an important energy carrier. An energy carrier moves a d delivers energy in a usable form to consumers. Renewable energy sources, like the sun and wind, can't produce energy all the time. But they could, for example, produce electric energy and hydrogen, which can be stored until it's needed. Hydrogen can also be transported (like electricity) to locations where it is needed [8] [10] [11]. V.

HYDROGEN S AFETY

Hydrogen is a fuel and is therefore combustible. Its combustion properties deserve the same caution that any fuel should be given. Hydrogen is not a particularly dangerous fuel, it disperses and evaporates much faster than gasoline that minimizes the explosion hazard. The hazards of hydrogen are different but not greater than normal fuels. Hydrogen can be handled carefully and safely, just like any other dangerous fuel such as gas e. Hydrogen tanks have been put through series of demanding safety tests. They have been completely engulfed in flames at over 1,650°F for up to 70 minutes, perforated by solid objects (such as armor -piercing bullets), and squeezed until they break with safety valves completely blocked. Sometimes the gas leaked out, sometimes it burnt, but it never exploded.

Figure 1 A transition to a “hydrogen economy” could extend some countries dependence on fossil fuels and nuclear power, while doing to solve the severe environmental problems caused by our dependence on polluting and dangerous sources of energy. Therefore the best pollutionfree alternative to batteries while still using clean ectric motors is the hydrogen fuel cell. Hydrogen-powered "fuel cells hold enormous promise as a power source for a future generation of cars. They do not have the restra nts that batteries do, either. Hydrogen is consumed by a pollution-free chemical reaction--not combustion--in a fuel cell. The fuel cell simply combines hydrogen and oxygen chemically to produce electricity, water, and waste heat. Hydrogen can be obtained from water by the process of electrolysis, or splitting water molecules using electricity.”

Mixing hydrogen with air shows a much wider concentration range capable of ignition, as compared to a mixture of gasoline / air. However, safety advantages the application of hydrogen reside in the relatively high ignition te mperature and the very low density. Hydrogen rises quickly and is thus rapidly diluted, therefore, hydrogen does not collect in pits or hollows; carpets f fire as in the case of escaping gasoline can be ruled ut. This is demonstrated in the below figure where a gasoline tank and a hydrogen pressure tank, respectively, have been ignited by a projectile fired from a rifle [16].

Hydrogen energy technologies can be used in both stationary and transport application in developed countries. In stationary applications, hydrogen energy technologies can be used to store excess energy from renewable, helping provide electricity to remote locations using original renewable energy sources. Given

VI.

ECONOMY OF HYDROGEN

Hydrogen economies confront many technical challenges and high set up costs mainly focused on

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3 rd Internatio na l G radu ate Conferen ce on Engineering, Science and Humanities (IGCESH) School o f Gradu ate Studies Universiti Tekn ologi Malaysia 2– 4 November 2010

transportation and storage. For making hydrogen vehicles practical, hydrogen fueling stations must be constructed and strategically located along roadways and in urban centers. The cost of the fuel stacks used in hydrogen production and consumption is too high that to be economically competitive w ith fossil fuel engines. This high cost is due to the precious metals required for reaction catalysts. Much of the current cost of hydrogen is associated with transportation and storage (including n the vehicle). The hydrogen economy is an offer for the distribution of energy by using hydrogen. Hydrogen (H2) gives off energy when it is combined with oxygen, but the hydrogen itself has to first be produced, which requir s more energy than is released when it is used as a fuel. To use hydrogen as a fuel, it first has to be generated by electrolysis of water or another method [1] [8].

Technological improvements to cut emissions from conventional cars cannot keep pace with the rising tide of vehicles. There will probably be a billion on the world's roads by 2020, one for every seven people. Hydrogen g is a combustible fuel just like oil or natural gas. But unlike them, it is ubiquitous, inexhaustible and clean. It can be made either by extracting it from a conventional hydrocarbon fuel, or by splitting water into its component elements: hydrogen and oxygen [1] [8] [17]. Hydrogen-fueled ICE's and gas turbine engines have negligible emissions of air pollutants. Hydrogen-poweredfuel -cell vehicles have zero emissions. On the other hand, platforms powered by petroleum-based fuels emit significant amounts of air pollutants air toxics and carbon dioxide. The health effects of these pollutants range rom headaches to serious respiratory damage such as lung cancer. Hydrogen will play a key role in solving the world’s energy problems. However, lingering technical challenges in hydrogen storage and delivery have precluded widespread use of hydrogen as an energy carrier for stationary and mobile applications. As a transportation fuel, hydrogen must be safe and costcompetitive with gasoline. The driving public is likel to reject transportation fuels that fail to meet these requirements. Hydrogen can be stored in gaseous, liquid, or solid form. Its characteristics in each of these st tes have profound implications for its ultimate use as a transportation fuel.

Hydrogen is an energy carrier, not a primary energy source .however, controversy over the usefulness of a hydrogen economy has been confused by issues of energy sourcing, including fossil fuel use, climate change, and sustainable energy generation [13]. Proponents of a world-scale hydrogen economy argue that hydrogen can be an environmentally cleaner source of energy to end-users, especially in transportation applications . Critics of a hydrogen economy argue that for many planned applications of hydrogen, direct distribu ion and use of energy in the form of electricity, or alternate means of storage such as chemical batteries, fuel plus fuel cells, or production of liquid synthetic fuels from locallyproduced hydrogen and CO2, might accomplish many of the same net goals of a hydrogen economy while requiri ng only a small fraction of the investment in new transportation. The least efficient and the most expensive possible replacement for gasoline (petrol) in terms of reducing greenhouse gases is hydrogen [1] [8] [9].

In liquid form, hydrogen has three major flaws. First, almost one -third of the energy originally contained in the fuel is lost in converting it to a liquid. Second, to liquid hydrogen for significant periods of time, temperatures near -253°C must be maintained. Third, most storage units for liquid hydrogen cannot prevent its slow conversion to a cold gas. Consequently, a car fueled with liquid hydrogen, parked at an airport for an extended period of time, will vent a sizable amount of gaseous hydrogen. In gaseous form, hydrogen’s main problem is its low energy density. As far as road vehicles are concerned, this basically means that even with a full nk of fuel the driving range is limited. In order to achieve an acceptable driving range, the fueling system must be very large or the gaseous hydrogen must be stored at a very high reassure. The latter is a safety risk that may be

Recent describing the use of low cost materials and manufacturing processes challenge the popular critique. Hydrogen can be produced from renewable sources, thus enabling the intermittent and excess power generated to be

stored for applications in transport, homes and busine es, thereby making off-grid wind and solar sources economic [12]. VII.

HYDROGEN AS F UEL O F THE FUTURE

unacceptable to customers. The most important benefit of hydrides is that there is significantly more hydrogen gas stored per unit volume This helps solve the driving range problem associated with gaseous hydrogen, because there is substantially more hydrogen available in the fueling system. Many believe that, rather than burning hydrogen, the key to the new fuel's success in the 21st century is likely to be the development of the hydrogen fuel cell -- a portable and versatile energy storage medium, rather like a soaped-up battery, that can power an electric motor.

The world is in the early stages of a long-term energy crisis. Fuel costs are suspended to rise further in the future. Although production of world conventional crude oil is at or near its peak, there is sufficient oil available fr m other fossil fuel sources to satisfy consumer demands for many years to come. Emissions of carbon dioxide from internal combustion engines are stoking the greenhouse effect faster than anything else. Burning oil in engines fills our cities with smog’s that kill hundreds of thousands every year.

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3 rd Internatio na l G radu ate Conferen ce on Engineering, Science and Humanities (IGCESH) School o f Gradu ate Studies Universiti Tekn ologi Malaysia 2– 4 November 2010

To take over the world, hydrogen will need a whole new hydrogen infrastructure, costing perhaps trillions of dollars. But we have to start somew here. Hence the interest in kick-starting the hydrogen economy either in smog hot-spots such as southern California, or in areas of abundant "green" energy for hydrogen production, such as Iceland. Iceland has the great advantage that you do not drive to or from it. It would be easy to convert the entire island to hydrogen.

[3] Yongliang Li, Haisheng Chen , Xinjing Zhang ,Chunq ing Tan and Yulo ng Ding ‘Renewab le energy carriers: H ydro gen or liq uid air/nitro gen ‘ , Applied T hermal Engineering 30 (20 10) 1985e1990 [4] C. koroneos , A . Dompros , G. Roumbas and N.Mous iop oulos ‘Life cycle assessment o f hydrogen fuel productio n p roc ses ‘ , Internatio nal Journal o f Hydro gen Energy 29 (2004) [5] Zhinan Xu, ‘B io lo gical Productio n of Hydrogen from Renewab le Reso urces’, Bioprocessing for Value-Added P roducts from Renewab le Reso urces Shang- Tian Yang (2007)

VIII. CONCLUSION

[6] Hazem Tawfik, C harles P .R ub enstein, N oel Blackma and Davinder Mahajan ‘Economic A nalys is of enewab le E nergy S ystems’, Institute fo r Research and Technology T ransfer , IEEE(2006)

Hydrogen can be mixed with natural gas to create an alternative fuel for vehicles that use certain types of internal combustion engines. Hydrogen is also used in fuel-cell vehicles that run on electricity produced by the petrochemical reaction that occurs when hydrogen and oxygen are combined in the fuel stack. Hydrogen safety covers the safe use and handling of hydrogen. Hydrogen poses unique challenges due to its ease of leaking, low-energy ignition, and wide range of combustible fuel -air mixtures, buoyancy, and its ability to embitter metals that must be accounted for to ensure safe operation. Liquid hydrogen poses additional challenges due to its increased density and extremely low temperatures. Hydrogen is touted as the energy carrier of the future. Most of the world's current supply of hydr gen is derived from fossil fuels and, therefore, most hydrogen does not eliminate the emission of (greenhouse gases) GHG pollutants that are connected with climate change. It is used today to make methanol, gasoline, heating oil, and rocket fuel. It is also used to make fertilizers, glass, refined metals, vitamins, cosmetics, semiconductor circuits, soaps, lubricants, cleaners, and even margarine and peanut butter. Hydrogen can fuel today’s internal combustion engine vehicles. Hydrogen can fuel tomorrow’s fuel-cell vehicles. Hydrogen can replace today’s natural gas for heating and cooling homes and powering hot water heaters. Existing wind and hydroelectric plants can produce hydrogen to

[7] K odjo Agbossou, Senior Member, IEEE, Mohanlal K olhe, Jean Hamelin, and Tapan K.Bose Member IEEE, ‘Performance o f a Stand Alone Renewab le E nergy S ystem Based on Energy S torage as Hydrogen’, IEEE,(2004) [8] Jiyo ng K im, Il Moon ,‘The role o f hydrogen in t road transportatio n secto r for a sustainable energy system , Internatio nal Journal of Hyd ro gen energy (2 0 0 8 ) [9] M.C onte, A. Laco bazzi, M. Ro nchetti and R.V ellone ‘H yd ro gen economy for a sustainab le development: state o f the ar and technological perspectives’, E lsevier Science (2001) [10]http ://www.hydrogennow.org [11]http ://www.renewab les.ca [12]http ://www.enviro nmentcalifornia.o rg [13]http ://www.eere.energy.gov [14] http ://www.alternative- energy- new.com

[15] http://www.hfc2009.com/ [16] http ://www.fueleco nomy.gov

[17] http://www.hyd rofuel.com.my/

store Hydrogen-fuel -cell-powered cars are the best alternatives to polluting, gasoline -powered cars for several reasons such as : (1) the cars are completely emissionfree,(2) hydrogen is renewable and abundant, (3) the fuel cells are compact and lightweight--not overly bulky or heavy, (4) the cars are about 3 times as efficient as gasoline-powered cars, (5) hydrogen is safe, has been tested rigorously for use in vehicles, and is being used in

many vehicles already. IX.

REFERENC ES

[1] Fernand o Hernandez S ob rino, C arlos Rod riguez monroy and Jo se luis Hernandez Perez: ‘Critical analysis on hyd rogen as an alternative to fossil fuels and b io fuels for vehicles in E urope ‘ , Renew ab le and S ustainab le E nergy R eviews 14 (2010) [2] Dimitri M ignard ,C olin Pritchard : ‘O n the use of electro lytic hyd rogen from variable renewab le energies for the enhanced conversion of b iomass to fuels ‘ ,chemical engineering research and design 8 6 ( 2 0 08)

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