During the 19th century, William Grove found that the energy produced by simple chemical reactions could be harnessed and exploited. His work led to the creation of the first alkaline one-kilowatt fuel cell system in the 1950’s. The power producing the potential of fuel cells was quickly adopted by NASA, which used them in the Gemini, Apollo, and space shuttle programs. Since their use in the 1960’s space programs, fuel cells have been improved and are becoming commercially available in products such as cars, computers, cell phones, residential and small business power generators, and large-scale stationary power generators. Fuel cells are also potential power providers for computers, credit card processing centers, jails, cellular towers, mining equipment, entertainment complexes, communication centers, navigation equipment, airports, road signs, defense installations, urban transit buses, and even vacuums.
Fuel cells rely on a relatively simple chemical reaction to generate energy. While there are different kinds of fuel cells, all with their unique characteristics, the general principle is the same across the board. A fuel cell is composed of an electrolyte sandwiched in between two electrodes. Electrodes are charged, usually metal plates. The electrolyte is the substance that hydrogen protons freely pass through as they move between electrodes. Electrolytes are made of different materials, and they are what usually give fuel cells their distinctive names.
The production of energy begins when a stream of hydrogen molecules is forced against the first electrode, called the anode, which is negatively charged. The anode forces the hydrogen molecule to split into protons and electrons. The protons are pulled through the electrolyte directly to the other electrode, called the cathode, which is positively charged. The electrons, having taken a different path around the electrolyte, are captured and used as an electrical current. These electrons then rejoin the protons in the cathode where they are both exposed to oxygen. The hydrogen and the oxygen combine to form pure potable water and some heat. Often, through a process known as cogeneration, this waste heat is captured and utilized in the heating and cooling of the facility where the fuel cell is located.
The fuel cell is only one part of a complete standard fuel cell system. There are three main parts. These three main parts are the fuel reformer, the fuel cell stack, and the power conditioner.
- The fuel reformer, usually through a process called steam reformation ( a process that creates carbon emissions ) isolates the pure hydrogen from a hydrocarbon fuel ( methane, ethanol, propane, natural gas, etc. ) This hydrogen, although pure, is sometimes referred to as dirty hydrogen due to the way it is created. This hydrogen is then put into the fuel cell stack.
- The fuel cell stack is any number of fuel cells stacked together to increase the produced energy output. The energy created by the fuel cell stack is in the form of direct current.
- The power conditioner, or the inverter, is the mechanism that inverts the direct current produced by the fuel cell into alternating current. The inverting of direct current into alternating current is required for most power applications to work.
Why are fuel cells attractive as alternative energy generators?
Fuel cells are attractive as energy generators because of their:
- Cleaner non-combustive operation. Fuel Cells emit no particulate matter and almost no NOx and SO2. While fuel cells still have some substantive CO2 emissions, they are only 45% that of coal generation and 47% the amount emitted from the production of energy using fossil fuels.
- Higher efficiencies when compared to combustion driven generators. Before even using cogeneration technologies in conjunction with the fuel cell, the cell is about 50%, and as much as 65%, efficient. Using cogeneration can boost efficiencies to as high as 90%. Compared to the 12-15% efficiency of most internal combustion engines, fuel cells are much more efficient.
- Ability to deliver reliable, uninterrupted power. In fact, a fuel cell in an integrated power supply system can provide 99.9999% reliability.
These are all welcome benefits in a time of unreliable polluting energy.
Types of fuel cells
There are various kinds of fuel cells. The basis of these multiple identities is founded on the difference in substance that is used as the electrolyte. This variation in electrolyte leads to different efficiencies, several heat outputs, and, therefore, preferred use in many applications. It is unlikely that one type of electrolyte will dominate all technology sectors. Instead, each type will probably fill specific technology niches depending on their relative advantages and disadvantages.
– Proton Exchange Membrane fuel cells (also known as PEM), which use a moist polymer membrane electrolyte, are the most common type of fuel cell. There are four basic elements of a PEM Fuel Cell. PEM cells run at cooler temperatures, perhaps as low as 41 degrees F, with average temperatures of about 80 degrees F that make them ideal for portable fuel cell technologies and small-scale residential applications. Their compact size, relatively low weight, quick start up, and ability to vary output to meet sudden shifts in power demands also make PEM fuel cells appealing to those looking to apply it in portable and smaller devices, light duty vehicles, and as replacements for rechargeable batteries. Their adverse qualities are high production costs, full maintenance, and repair requirements. These are problems not limited to PEM cells.
– Phosphoric Acid fuel cells (PA fuel cells) are another major type of fuel cell and are currently installed in over 200 systems globally. PA fuel cells, which use an immobilized liquid form of phosphoric acid as its electrolyte, have higher operating temperatures of around 200 degrees C. This warmer temperature makes cogeneration, using the steam produced as a byproduct, a somewhat more appealing option for those employing this type of fuel cell. However, this higher temperature also restricts the use of PA cells to stationary applications. Personal electronic devices, such as mobile phones, laptops, or even cars, would most likely not use PA fuel cells.
– Molten Carbonate fuel cells are a third type of fuel cell. They use an immobilized liquid form of an alkali carbonate mixture as an electrolyte. Molten Carbonate cells have even higher operating temps of around 650 degrees C. These cells are currently fueled by a wide variety of fuels including pure hydrogen, carbon monoxide, natural gas, propane, methane, marine diesel, and stimulate coal gasification products. Stationary applications of these cells have been successfully demonstrated in Japan and Italy.
– Solid Oxide (SO) fuel cells, which utilize a solid ceramic yttria stabilized zirconia electrolyte, have a much higher operating temperature of 980 degrees C or more. For this reason, SO fuel cells are most often used in the major high-power applications such as industrial and large-scale electrical generating stations. This type of fuel cell has the highest efficiency at about 60%. Because of their high heat output, when cogeneration is used with SO fuel cell efficiencies can reach as much as 90%.
– Other types of fuel cells include: Alkaline fuel cells, which were used by the NASA space program (with efficiencies of 70%); Direct Methanol fuel cells, which draw the hydrogen out of the methane without the assistance of a fuel reformer; and Regeneration fuel cells, which utilize a solar-powered electrolyzer and their own waste water to form a self-contained regenerative system. Today, fuel cells are used commercially or in researches.
Where do we get all of the hydrogen necessary to power fuel cells?
It is estimated that the typical household with a fuel cell system with a 40% efficiency, using 24 kWh per day, will need 21,500 ft3 of hydrogen a year to generate energy. That is roughly 60 ft3 a day.
Where is all of this hydrogen going to come from?
Hydrogen is the most abundant element in nature. However, it is usually not found on its own but instead in conjunction with other elements. For this reason, it is necessary to separate hydrogen out of substances that contain hydrogen. The most common substance thus far has been the hydrocarbon natural gas. Currently, the US uses more than 3.2 trillion ft3 of hydrogen per year, mostly derived from reforming natural gas. While using natural gas in a fuel cell is better than using it in a combustion engine, it is still not renewable or emission free. A source of pure non-reformed hydrogen is needed to become entirely renewable and emission-free. Research on a low cost and efficient way to obtain large amounts of hydrogen has been going on for some time now. While it is true that fuel cells have evolved with the help of non-renewable fossil fuels, it is imperative that we discover a way to produce pure (and therefore clean) hydrogen. An infrastructure, which can deliver and transport massive amounts of hydrogen safely and efficiently must also be developed. The following are some examples of the current techniques for capturing pure hydrogen.
There is four basic methods of obtaining pure (not extracted from fossil fuel hydrocarbons) hydrogen. The methods are: thermochemical, electrochemical, photoelectrochemical, and photobiological.
- Thermochemical technologies use a steam reforming process to produce hydrogen from fuels such as gasified biomass, natural gas, coal, methanol, and gasoline. This includes processes that obtain hydrogen from switchgrass grown on marginal land.
- Electrochemical techniques rely on the electrolysis of water to produce hydrogen. This is nothing more than passing an electrical current through the water.
- Photoelectrochemical Processes split water, and hence produce hydrogen, by illuminating a water-immersed semiconductor with sunlight. Clean hydrogen (hydrogen not derived from fossil fuels) is most commonly produced using photoelectrochemical processes through the exploitation of solar panels. The solar panels produce electricity to electrically split water into hydrogen and oxygen through a process known as electrolysis. However, the cost of solar panels does not make this process economically competitive with the production of hydrogen from fossil fuels. It is perhaps better to just use the electricity straight from the solar panels, rather than using it to make hydrogen that will be used in fuel cells to make electricity.
- Photobiological methods use the natural photosynthetic activity of bacteria and green algae to produce hydrogen. This process is sometimes called biophotolysis. The University of Hawaii has built a processing plant with a development scale bioreactor.
There are also some researchers that are using wind turbines to make electricity, which is then used to electrolyze (split) water, releasing pure hydrogen.
Why aren’t more fuel cells being used today?
The main reason for the lack of use of fuel cells today is that fuel cells are relatively very expensive. The cost of producing and using fuel cells is still high because of the lack of mass production. Like any other young technology, it must be fine-tuned and then mass-produced before it becomes a more economical option for the consumer.
How do fuel cells affect the environment?
Fuel cells, when powered by pure, clean hydrogen not acquired through the reformation of fossil fuels, are total emission free. The only products of the cell, besides electric current, are heat and pure potable H2O. Through cogeneration of the heat into steam and regeneration of the water using the process of electrolyzation, even these byproducts are utilized. In the case that they are not utilized, there is still no harm done to the surrounding environment.
The reality, however, is that pure hydrogen is rarely used except for in laboratory studies. Steam reformers are often used to isolate the hydrogen out of hydrocarbon fuels. Steam reformation is the process of combining steam with a hydrocarbon to isolate the hydrogen. The resulting CO2 emissions are lower than those from a combustion engine. Steam reformation emits zero to small amounts of NOx and SO2.
Even though the use of fossil fuels such as natural gas and propane is not totally emissions free and not renewable, the use of these fuels to power fuel cells is cleaner than the use of combustion engines and will allow for the continued improvement of fuel cells. Fuel cells are more environmentally sound than conventional energy technologies. Below is a comparison of the amount of pollution produced by fuel cells versus conventional energy technologies.
– Fuel Cell Engine vs. Gasoline Engine
In the US, passenger vehicles alone consume 6 million barrels of oil a day. If 10,000 vehicles were to be powered by fuel cells, oil consumption would be reduced by as much as 6.98 million gallons per year. According to the Department of Energy, if 10% of automobiles in the US were powered by fuel cells, 60 million tons of CO2 would be kept from entering the atmosphere. Furthermore, massive amounts of other greenhouse gasses such as NOx and SO2 would be reduced as well as a lessened demand for the harmful drilling of oil amidst finely tuned fragile ecosystems.
– Fuel Cell Generation vs. Standard Coal and Oil Generation
Compared to the emissions created by conventional stationary power plants, fuel cells are much less emissive. Solid Oxide (SO) fuel cells emit less than coal and oil generators.
– Fuel Cell Generator vs. Diesel Generator
Compared to the emissions created by the most commonly used form of micropower, the diesel generator, fuel cells are much cleaner for the environment. Diesel generators produce enormously large amounts of NOx and particulate matter, far more than fuel cells almost zero emissions of these two climate-changing substances.
Almost all the well-known auto manufacturers plan for FCEV development and commercialization.
Why don’t we put a fuel cell on the moon and beam the energy back to Earth?
Although almost 1/3 of the moon’s thin atmosphere is composed of hydrogen, the idea of creating electricity that will have to be beamed 384,400 kilometers to be used is problematic at best. By current technology, electricity travels along transmission cables that are inefficient and very expensive: high voltage cables can cost thousands of dollars per mile, which is part of why there are people on earth that cannot get electricity. Even if Bill Gates were to decide to fund such an operation, there exists no transmission cable that could maintain a current for the distance between the earth and the moon. Since even the best cables experience power losses of about 10% just between the standard earth-bound generating plant and its earthling customer, the electric current would never make the journey to the moon and back to the earth. Also, terrible tangling of the cables would occur due to the incongruent orbital and rotational patterns of the earth and the moon. It would be much more efficient and cost-effective to produce energy using fuel cells. But maybe in the future, we can wirelessly transmit the hydrogen energy from the moon to the earth.
Katika karne ya 19, William Grove aliona kwamba nishati inayotokezwa na athari rahisi za kemikali inaweza kutumiwa kwa njia fulani. Kazi yake ilisababisha kuundwa kwa mfumo wa kwanza wa alkaline wa kilowatt moja ya seli za mafuta katika miaka ya 1950. Kwa sababu ya uwezo wa kuendesha ndege, NASA ilitumia chombo hicho katika mipango ya Gemini, Apollo, na Space Shuttle. Tangu matumizi yao katika programu za anga za miaka ya 1960, seli za mafuta zimeboreshwa na zinapatikana kibiashara katika bidhaa kama vile magari, kompyuta, simu za mkononi, jenereta za umeme za makazi na biashara ndogo, na jenereta za umeme za kudumu za kiwango kikubwa. Vipuli vya mafuta pia ni watoaji wa nguvu wa uwezekano kwa kompyuta, vituo vya usindikaji wa kadi za mkopo, magereza, minara ya simu, vifaa vya uchimbaji madini, vituo vya burudani, vituo vya mawasiliano, vifaa vya urambazaji, viwanja vya ndege, ishara za barabara, mitambo ya ulinzi, mabasi ya usafiri wa mijini, na hata vacuums. Chembe za mafuta hutegemea mmenyuko rahisi wa kemikali ili kutokeza nishati. Ingawa kuna aina mbalimbali za chembe za mafuta, zote zikiwa na sifa zao za kipekee, kanuni ya jumla ni ileile katika bodi. Chembe ya mafuta hufanyizwa na elektroni iliyo kati ya elektroni mbili. Electrodes ni kushtakiwa, kawaida sahani chuma. Elektroliti ni dutu ambayo protoni za hidrojeni hupita kwa uhuru zinapotembea kati ya elektroni. Elektroliti hutengenezwa kwa vifaa tofauti-tofauti, na kwa kawaida hizo ndizo zinazotoa majina ya kipekee kwa chembe za mafuta. Mzunguko wa molekuli za hidrojeni huanza wakati umeme wa kwanza unaoitwa anode unapopigwa na umeme wa hasi. Anodi hiyo husababisha molekuli ya hidrojeni kugawanyika katika protoni na elektroni. Protoni huchukuliwa kupitia elektroni moja kwa moja hadi kwenye elektroni nyingine, iitwayo cathode, ambayo ina nishati nzuri. Elektroni, baada ya kuchukua njia tofauti kuzunguka elektroliti, zinakamatwa na kutumiwa kama mkondo wa umeme. Kisha elektroni hizo hujiunga tena na protoni katika katodi ambapo zote mbili hufunuliwa na oksijeni. Hidrojeni na oksijeni huungana na kutokeza maji safi ya kunywa na joto fulani. Kwa kawaida, kupitia mchakato unaojulikana kama cogeneration, joto hili la taka linakamatwa na kutumiwa katika joto na baridi ya kituo ambapo seli ya mafuta iko. Chembe ya mafuta ni sehemu moja tu ya mfumo kamili wa chembe ya mafuta ya kawaida. Kuna sehemu kuu tatu. Sehemu hizi tatu kuu ni reformer mafuta, stack mafuta kiini, na conditioner nguvu. Reformer ya mafuta, kwa kawaida kupitia mchakato unaoitwa uundaji wa mvuke (mchakato ambao huunda uzalishaji wa kaboni), hutenganisha hidrojeni safi kutoka kwa mafuta ya hidrokarboni (methani, ethanoli, propani, gesi asilia, nk). Ingawa hidrojeni hiyo ni safi, nyakati nyingine huitwa hidrojeni chafu kwa sababu ya jinsi inavyoundwa. Kisha hidrojeni hiyo huwekwa ndani ya kiunzi cha chembe za mafuta. - stack ya seli ya mafuta ni idadi yoyote ya seli za mafuta stacked pamoja ili kuongeza pato la nishati zinazozalishwa. Nishati inayotokezwa na stack ya seli ya mafuta ni katika fomu ya sasa ya moja kwa moja. - Power conditioner, au inverter, ni utaratibu kwamba inverts moja kwa moja sasa zinazozalishwa na seli ya mafuta katika mzunguko wa sasa. Inverting ya moja kwa moja sasa katika mzunguko wa sasa inahitajika kwa ajili ya maombi mengi ya nguvu ya kazi. Kwa nini chembe za mafuta zinavutia kama vyanzo vingine vya nishati? Fuel cells ni kuvutia kama jenereta ya nishati kwa sababu ya yao: - Safi yasiyo ya moto uendeshaji. Kwa mfano, chembe za mafuta hazitoi chembechembe za nyuzinyuzi, na hazitoi NOx na SO2. Ingawa seli za mafuta bado zina uzalishaji mkubwa wa CO2, ni 45% tu ya uzalishaji wa makaa ya mawe na 47% ya kiasi kilichotolewa kutoka kwa uzalishaji wa nishati kwa kutumia mafuta ya mafuta. - ufanisi wa juu ikilinganishwa na jenereta inayoendeshwa na mwako. Kwa mfano, kabla ya kuanzisha teknolojia ya cogeneration, kwa mfano, kwa kutumia chembe za mafuta, kwa mfano, kwa kutumia chembe za mafuta, kwa mfano, kwa kutumia chembe za mafuta, kwa mfano, kwa kutumia chembe za mafuta, kwa mfano, kwa kutumia chembe za mafuta. Kwa kutumia cogeneration, unaweza kuongeza ufanisi hadi 90%. Kwa kulinganisha na ufanisi wa 12-15% wa injini nyingi za mwako wa ndani, seli za mafuta zina ufanisi zaidi. - Uwezo wa kutoa nguvu ya kuaminika, isiyo na kukatika. Kwa kweli, chembe ya mafuta katika mfumo wa usambazaji wa umeme wa pamoja inaweza kutoa uaminifu wa 99.9999%. Hizi zote ni faida zinazopendwa katika wakati wa nishati isiyoaminika na yenye kuchafua. Aina ya seli za mafuta Kuna aina mbalimbali za seli za mafuta. Msingi wa utambulisho huu mbalimbali unategemea tofauti katika dutu inayotumiwa kama electrolyte. Tofauti hii katika electrolyte inaongoza kwa ufanisi tofauti, pato kadhaa la joto, na, kwa hiyo, matumizi ya kupendelea katika maombi mengi. Haishangazi kwamba aina moja ya electrolyte itatawala sekta zote za teknolojia. Badala yake, kila aina ya pengine kujaza niche maalum ya teknolojia kulingana na faida zao za jamaa na hasara.  Proton Exchange Membrane Fuel Cells (PEM) ni aina ya kawaida ya mafuta ya chembe. Kuna vipengele vinne vya msingi vya PEM Fuel Cell. PEM seli huendesha katika joto la chini, labda chini ya 41 ° F, na joto la wastani la karibu 80 ° F, ambayo hufanya kuwa bora kwa teknolojia za seli za mafuta za kubeba na matumizi madogo ya makazi. Ukubwa wao mdogo, uzito mdogo, kuanza haraka, na uwezo wa kubadilisha pato ili kukidhi mabadiliko ya ghafla katika mahitaji ya nguvu pia hufanya PEM seli za mafuta kuwavutia kwa wale wanaotafuta kuitumia katika vifaa vya kubebeka na vidogo, magari ya kazi nyepesi, na kama mbadala wa betri za kuchaji. Sifa zao mbaya ni gharama za juu za uzalishaji, matengenezo kamili, na mahitaji ya ukarabati. Matatizo haya hayakumalizika kwa chembe za PEM. Phosphoric asidi mafuta seli (PA) ni aina nyingine kuu ya mafuta seli na kwa sasa ni imewekwa katika zaidi ya 200 mifumo duniani kote. Chembe za mafuta za PA, ambazo hutumia aina ya kioevu ya asidi ya phosphoric kama electrolyte yake, zina joto la juu la kufanya kazi ya karibu 200 ° C. Joto hili la joto hufanya cogeneration, kwa kutumia mvuke uliotengenezwa kama bidhaa, chaguo la kuvutia zaidi kwa wale wanaotumia aina hii ya chembe za mafuta. Hata hivyo, joto hili la juu pia hupunguza matumizi ya seli za PA kwa matumizi ya kudumu. Vifaa vya elektroniki vya kibinafsi, kama vile simu za mkononi, kompyuta ndogo, au hata magari, kwa uwezekano mkubwa haitatumia seli za mafuta za PA.  Chembe za mafuta za Carbonate zilizochemka ni aina ya tatu ya chembe za mafuta. Wao hutumia aina ya kioevu isiyoweza kusonga ya mchanganyiko wa alkali carbonate kama electrolyte. Chembe za kaboni zilizochemka zina joto la juu zaidi la kufanya kazi, karibu digrii 650 C. Chembe hizi kwa sasa zinaendeshwa na aina mbalimbali za mafuta, ikiwa ni pamoja na hidrojeni safi, kaboni monoksidi, gesi asilia, propani, methani, dizeli ya baharini, na kuchochea bidhaa za gasification ya makaa ya mawe. Matumizi ya vituo hivi yameonyeshwa kwa mafanikio nchini Japani na Italia. Chembe za mafuta za Solid Oxide (SO) ambazo hutumia electrolyte ya zirconia iliyowekwa imara na yttria ya udongo, zina joto la juu zaidi la uendeshaji la digrii 980 C au zaidi. Kwa sababu hii, SO fueli seli ni mara nyingi kutumika katika maombi makubwa ya nguvu kama vile viwanda na kubwa-scale umeme vituo vya uzalishaji. Aina hii ya chembe za mafuta ina ufanisi wa juu zaidi, karibu 60%. Kwa sababu ya uzalishaji wao wa joto, wakati cogeneration hutumiwa na SO, ufanisi wa seli za mafuta unaweza kufikia asilimia 90. Aina nyingine za seli za mafuta ni pamoja na: seli za mafuta ya alkali, ambazo zilitumiwa na mpango wa anga wa NASA (kwa ufanisi wa 70%); seli za mafuta za Methanol ya moja kwa moja, ambazo huchukua hidrojeni kutoka kwa methane bila msaada wa reformer ya mafuta; na seli za mafuta za Regeneration, ambazo hutumia electrolyzer ya nishati ya jua na maji yao ya taka kuunda mfumo wa kujirekebisha. Leo, chembe za mafuta hutumiwa kibiashara au katika utafiti. Tunapata wapi hidrojeni yote inayohitajika kuendesha seli za mafuta? Inakadiriwa kwamba nyumba ya kawaida na mfumo wa chembe za mafuta na ufanisi wa 40% kwa kutumia 24 kWh kwa siku itahitaji 21,500 ft 3 ya hidrojeni kwa mwaka ili kuzalisha nishati. Hiyo ni karibu mita 60 kwa siku. Hizi hidrojeni zote zitatoka wapi? Hidrojeni ndiyo elementi iliyo nyingi zaidi katika asili. Hata hivyo, kwa kawaida haipatikani peke yake bali kwa kushirikiana na vitu vingine. Kwa sababu hiyo, ni muhimu kutenganisha hidrojeni kutoka kwa vitu vinavyo na hidrojeni. Kiasi cha kawaida hadi sasa imekuwa hidrokarboni gesi ya asili. Kwa sasa, Marekani hutumia zaidi ya trilioni 3.2 za futi za hidrojeni kwa mwaka, hasa zinazotokana na kurekebisha gesi asilia. Wakati kutumia gesi ya asili katika seli ya mafuta ni bora kuliko kuitumia katika injini ya mwako, bado si mbadala au uzalishaji bure. Chanzo cha hidrojeni safi isiyofanywa upya inahitajika kuwa upya kabisa na bila uzalishaji. Utafiti juu ya njia ya bei nafuu na yenye ufanisi ya kupata kiasi kikubwa cha hidrojeni umekuwa ukiendelea kwa muda fulani sasa. Ingawa ni kweli kwamba seli za mafuta zimebadilika kwa msaada wa mafuta yasiyoweza kurekebishwa, ni lazima tujue njia ya kutengeneza hidrojeni safi (na kwa hivyo safi). Miundombinu, ambayo inaweza kutoa na kusafirisha kiasi kikubwa cha hidrojeni kwa usalama na ufanisi lazima pia kuendelezwa. Yafuatayo ni baadhi ya mifano ya mbinu za sasa kwa ajili ya kukamata hidrojeni safi. Kuna mbinu nne za msingi za kupata hidrojeni safi (isiyotokana na hidrokarboni za mafuta ya visukuku). Mbinu hizo ni: thermochemical, electrochemical, photoelectrochemical, na photobiological. - Teknolojia za thermochemical hutumia mchakato wa kurekebisha mvuke kutengeneza hidrojeni kutoka kwa mafuta kama vile biomass ya gesi, gesi asilia, makaa ya mawe, methanol, na petroli. Hii inajumuisha michakato ambayo hupata hidrojeni kutoka switchgrass kukua juu ya ardhi marginal. - Mbinu za umeme za kemikali hutegemea electrolysis ya maji kutokeza hidrojeni. Hii ni kitu kingine ila kupitisha mkondo wa umeme kupitia maji. -Mchakato wa photoelectrochemical kugawanya maji, na hivyo kuzalisha hidrojeni, kwa kuangaza maji-immersed semiconductor na mwanga wa jua. Hydrogen safi (hydrogen si inayotokana na mafuta ya makaa ya mawe) ni kawaida zinazozalishwa kwa kutumia photoelectrochemical taratibu kwa njia ya matumizi ya paneli za jua. Paneli za jua hutengeneza umeme ili kugawanya maji kwa umeme kuwa hidrojeni na oksijeni kupitia mchakato unaojulikana kama electrolysis. Hata hivyo, gharama ya paneli za jua haifanyi mchakato huu ushindani kiuchumi na uzalishaji wa hidrojeni kutoka kwa mafuta ya visukuku. "Hata hivyo, ni bora kutumia umeme kutoka kwa paneli za jua badala ya kutumia umeme kutoka kwa ""seli za mafuta"" za umeme." - Mbinu za photobiological hutumia shughuli ya asili ya photosynthetic ya bakteria na algae ya kijani ili kuzalisha hidrojeni. Nyakati nyingine utaratibu huo huitwa biophotolysis. Chuo Kikuu cha Hawaii kimejenga kiwanda cha usindikaji chenye bioreactor ya kiwango cha maendeleo. Watafiti wa kisasa wanafanya kazi na turbine za upepo, ambazo hutumia umeme kutengeneza maji safi. Kwa nini si seli za mafuta zaidi zinazotumiwa leo? Sababu kuu ya ukosefu wa matumizi ya seli za mafuta leo ni kwamba seli za mafuta ni ghali sana. Gharama ya kuzalisha na kutumia seli za mafuta bado ni kubwa kwa sababu ya ukosefu wa uzalishaji wa wingi. Kama teknolojia nyingine yoyote mpya, lazima ifanye marekebisho na kisha itengenezwe kwa wingi kabla ya kuwa chaguo la kiuchumi zaidi kwa watumiaji. Seli za mafuta huathirije mazingira? Chembe za mafuta, zinapokuwa na nguvu na hidrojeni safi, safi ambayo haijapatikana kupitia marekebisho ya mafuta ya visukuku, hazina uzalishaji kabisa. Bidhaa pekee za seli, pamoja na umeme, ni joto na H2O safi ya kunywa. Kupitia cogeneration ya joto katika mvuke na regeneration ya maji kwa kutumia mchakato wa electrolysis, hata bidhaa hizi ni kutumika. Katika hali ambayo hazitumiwi, bado hakuna madhara yanayotokea kwa mazingira yanayozunguka. Hata hivyo, ukweli ni kwamba hidrojeni safi hutumiwa mara chache sana isipokuwa katika majaribio ya maabara. Mara nyingi vifaa vya kurekebisha mvuke hutumiwa kutenganisha hidrojeni kutoka kwa mafuta ya hidrokarboni. Marekebisho ya mvuke ni mchakato wa kuchanganya mvuke na hidrokarboni kutenganisha hidrojeni. Matokeo ya uzalishaji wa CO2 ni chini kuliko wale kutoka injini ya mwako. Utaratibu wa ufumbuzi wa mvuke hutokeza kiasi kidogo cha NOx na SO2. Hata kama matumizi ya mafuta kama vile gesi ya asili na propane si kabisa uzalishaji bure na si upya, matumizi ya mafuta haya kwa nguvu ya mafuta seli ni safi kuliko matumizi ya injini ya mwako na kuruhusu kwa ajili ya kuendelea kuboresha mafuta seli. Chembe za mafuta ni salama zaidi kwa mazingira kuliko teknolojia za kawaida za nishati. Chini ni kulinganisha ya kiasi cha uchafuzi zinazozalishwa na seli za mafuta dhidi ya teknolojia ya kawaida ya nishati.  Injini ya Chembe za Mafuta dhidi ya Kwa mfano, katika nchi za Ulaya, magari ya abiria hutumia kiasi cha marijani milioni sita kwa siku. Ikiwa magari 10,000 yangetumia mafuta ya chembe za mafuta, matumizi ya mafuta yangepunguzwa kwa galoni milioni 6.98 kwa mwaka. Kulingana na Idara ya Nishati, ikiwa asilimia 10 ya magari nchini Marekani yangeendeshwa na seli za mafuta, tani milioni 60 za CO2 zingehifadhiwa kutoka kwa angahewa. Kwa kuongezea, kiasi kikubwa cha gesi nyingine za chafu kama vile NOx na SO2 zitapunguzwa na mahitaji ya kuchimba mafuta yenye madhara yatapunguzwa katikati ya mifumo ya ikolojia dhaifu. <unk> Fuel Cell Generation vs. Standard Coal na Oil Generation Ikilinganishwa na uzalishaji ulioundwa na mitambo ya umeme ya kawaida, seli za mafuta zina uzalishaji mdogo sana. Solid Oxide (SO) seli za mafuta hutoa chini ya makaa ya mawe na jenereta za mafuta.  Fuel Cell Generator vs. Diesel Generator Ikilinganishwa na uzalishaji ulioundwa na aina ya kawaida ya micropower, jenereta ya dizeli, seli za mafuta ni safi zaidi kwa mazingira. Kwa mfano, jenereta za dizeli hutokeza kiasi kikubwa cha oksidi ya nitrojeni (NOx) na chembechembe, zaidi ya chembe za mafuta, na karibu kutokeza uzalishaji wa vitu hivi viwili vinavyobadilisha hali ya hewa. Karibu wazalishaji wote wa magari wanaojulikana wanapanga maendeleo na uuzaji wa FCEV. Kwa nini tusipige chembe ya mafuta kwenye mwezi na kupeleka nishati hiyo arudi Duniani? Ingawa karibu theluthi moja ya anga la mwezi lina hidrojeni, wazo la kutengeneza umeme ambao utahitaji kupelekwa umbali wa kilomita 384,400 ili utumiwe ni tatizo. Kwa teknolojia ya sasa, umeme husafiri kwenye nyaya za usafirishaji ambazo hazina ufanisi na ni ghali sana: nyaya za voltaji ya juu zinaweza kugharimu maelfu ya dola kwa maili, ambayo ni sehemu ya sababu kuna watu duniani ambao hawawezi kupata umeme. Hata kama Bill Gates angeamua kufadhili operesheni kama hiyo, hakuna kebo ya usafirishaji ambayo ingeweza kudumisha mkondo kwa umbali kati ya dunia na mwezi. Kwa kuwa hata nyaya bora zaidi hupata hasara ya nguvu ya karibu 10% kati tu ya kiwanda cha kawaida cha kuzalisha cha ardhi na mteja wake wa dunia, mkondo wa umeme haungeweza kamwe kufanya safari ya mwezi na kurudi duniani. Pia, nyaya hizo zingevunjika-vunjika kwa sababu ya mpangilio usio sawa wa mzunguko na mzunguko wa dunia na mwezi. Ingekuwa na ufanisi zaidi na gharama nafuu kuzalisha nishati kwa kutumia seli za mafuta. Lakini labda katika siku zijazo, tunaweza kuhamisha nishati ya hidrojeni kutoka mwezi hadi duniani bila waya.