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  • Why Batteries Are Not the Future
     
    The announcement in April by Tesla Motors that more than 325,000 people had deposited $1,000 each for its new Model 3 suggests that consumer demand for battery-powered electric cars is growing. As The New York Times reported, last year Tesla sold only 50,000 of its current electric vehicles, the Model S and Model X.1


    Unfortunately for the Model 3 buyers, their quest to own ¡°the next new thing,¡± could quickly sour into the realization that they¡¯re stuck with ¡°the last old thing¡± when a superior technology comes along.


    That¡¯s precisely what the Trends editors anticipate will happen when fuel cell technology bursts onto the market in the next few years.


    According to Business Insider, sales figures from Motor Intelligence and Inside EVs reveal that Americans bought less than 114,000 electric vehicles (EVs) in 2015. That¡¯s just 1.4 percent of the car market, and it¡¯s a smaller share than in 2014.2


    The number isn¡¯t likely to jump in 2016 either, because the Tesla 3 won¡¯t be manufactured until next year. Even if all 325,000 of the customers who paid a deposit for the car actually take delivery in 2017, tripling the size of the EV market would only increase it to 4.2 percent.


    Why hasn¡¯t the market for EVs grown faster? Electric cars are severely limited by several drawbacks, including:


    - A shortage of charging stations.


    - High electricity costs.


    - Disappointing battery capacity that limits the distance the cars can be driven between charges.


    - Painfully long charging times. (According to the pro-EV organization Plug In America, ¡°To recharge a completely empty car battery from an ordinary 120-volt socket, the Chevy Volt plug-in hybrid would need ten hours and the Nissan Leaf EV would need twenty hours. Using a faster 240-volt outlet and a charging station, the Volt recharges in about four hours and the Leaf in eight hours.¡±)


    Meanwhile, researchers have made significant progress in perfecting fuel cell technology.


    According to Merten Jung, who leads the fuel cell program at BMW, which also makes plug-in electric cars, ¡°[A] fuel cell drivetrain combines zero-emissions mobility with the fast refueling time that¡¯s needed for long-distance driving. Moving forward, electric vehicles will have longer ranges thanks to advances in battery technology, but the refueling time won¡¯t be competitive with that of a hydrogen-powered model. It takes about three to five minutes to top up a hydrogen tank, and then you¡¯re set to go.¡±3 To repeat: That¡¯s three to five minutes, compared to four to twenty hours.


    Jung explained to Digital Trends that, aside from the superior energy technology, there¡¯s little difference between an electric vehicle and one powered by fuel cells.4 As he put it, ¡°The basic idea is that you take an EV with a large battery pack, and you replace the pack with a fuel cell, a hydrogen tank, and a smaller battery. From there on, the drivetrain is identical; the electric motor, the electronics, the gearbox, it¡¯s all the same?and they have the same driving experience, too. In both cases, it¡¯s pure electric so you can¡¯t tell the difference between the two when you¡¯re behind the wheel.¡±
     
    However, the difference becomes evident when the car needs to be recharged. That¡¯s where fuel cells have an advantage.


    According to University of Delaware Distinguished Engineering Professor Yushan Yan, ¡°Both fuel cells and batteries are clean technologies that have their own sets of challenges for commercialization. The key difference, however, is that the problems facing battery cars, such as short driving range and long battery charging time, are left with the customers. By contrast, fuel cell cars demand almost no change in customer experience because they can be charged in less than five minutes and be driven for more than 300 miles in one charge.¡±5


    The challenges for fuel cells are engineering challenges, not customer challenges. So, as an engineer, Yan worked on fixing the primary issue that keeps fuel cells from being used by car manufacturers: their relatively high cost, due to the need to use expensive platinum catalysts.


    Yan¡¯s team experimented with other metals to take the place of platinum. As they reported in Nature Communications, they discovered that they could get the same results by using nickel - which is a much cheaper metal - by changing the operating environment from acidic to basic.6 The result is a breakthrough called a miniaturized solid oxide fuel cell (SOFC) using an oxide-based thin-film electrode and porous stainless steel substrate.


    According to Yan, ¡°This new hydroxide exchange membrane fuel cell can offer high performance at an unprecedented low cost. Our real hope is that we can put hydroxide exchange membrane fuel cells into cars and make them truly affordable - maybe $23,000 for a Toyota Mirai. Once the cars themselves are more affordable, that will drive development of the infrastructure to support the hydrogen economy.¡±


    Other research on miniaturized SOFCs demonstrates the potential for fuel cells to supplant lithium-ion batteries in everything from drones to phones.


    At the Pohang University of Science & Technology (POSTECH) a team led by Professor Gyeong Man Choi of the Department of Materials Science and Engineering showed that a drone powered by an SOFC can fly for more than an hour. That¡¯s much longer than a drone can stay in the air when it is powered by a lithium-ion battery.


    As Choi and his colleagues reported in Scientific Reports, the sister journal of Nature, SOFCs could replace batteries in every device that needs high power density and the ability to turn on and off quickly, including smartphones, laptops, and cars. For example, a phone that runs on a fuel cell would only need to be charged once a week.


    These breakthroughs have resolved almost all of the problems previously associated with both batteries and fuel cells, such as:


    - Lack of fueling infrastructure: SOFCs can run on a wide range of fuels, including methanol, natural gas, and even gasoline. That means that they can be fueled in most places that cars are fueled right now.


    - High cost of electricity: Electricity is expensive to generate and transmit. A natural gas fueled SOFC can produce electricity at a lower cost than the electric utility used to recharge batteries.


    - Shortage of materials: Lithium-ion batteries require materials that are in relatively short supply. Unlike most other types of fuel cells, SOFCs don¡¯t require the use of expensive catalysts like platinum in order to operate efficiently.


    Looking ahead, we foresee the following developments emerging from this trend:


    First, car buyers will embrace vehicles that run on fuel cells once the infrastructure is in place.


    According to BMW¡¯s Jung, ¡°There are initiatives in various countries to set up an infrastructure. In Germany, the government has plans to install 100 hydrogen stations by 2018, which is sufficient to set up an initial network, and there will be up to 400 additional stations by 2023; the final number will depend on how many hydrogen-powered vehicles are on the road by then. The advantage is that you can convert existing gas stations to hydrogen stations, so you can build the network step-by-step.   In Europe, the leaders are Germany, the United Kingdom, and Scandinavian nations. In the United States, hydrogen is becoming increasingly popular in California, and Japan is making a big investment in the technology.¡± Not coincidentally, BMW plans to target each of those markets when it introduces its hydrogen-powered cars after 2020.


    Second, fuel cells will enable homeowners to generate energy from natural gas.


    According to Science magazine, Colorado School of Mines researchers led by Professor Ryan O¡¯Hayre determined that homes could use natural gas for power generation more efficiently through the use of fuel cells that convert the chemical energy of a fuel source into electrical energy close to where it is used. Consumers would benefit by having access to an energy source that would be more reliable, more environmentally friendly, and cheaper than the current electrical grid.8 As O¡¯Hayre explains, ¡°Our work demonstrates a proton-conducting ceramic fuel cell that generates electricity off either hydrogen or methane fuel and runs at much lower temperatures than conventional ceramic fuel cells. We achieved this advance by developing a new air electrode for our fuel cell that is highly active even at lower temperatures because it is a triple-conducting electrode (it conducts electron holes, oxygen ions, and protons all at the same time) and we applied a relatively new fabrication method that greatly reduces the complexity and cost for the fuel cell fabrication.¡±


    Third, SOFCs will not only eliminate the economic rationale for battery vehicles, they will cut electricity costs via decentralized generation.


    According to research from the Department of Energy¡¯s Pacific Northwest National Laboratory published in the journal Fuel Cells, natural gas powered solid oxide fuel cells, located onsite, would provide energy for at least 33 percent less than a centralized supplier would charge.9 That estimate is deliberately conservative because it assumes that facilities that pay for natural gas individually would buy it at twice the rate that a centralized plant would pay due to its larger scale. Eventually, the researchers believe that fuel cells will be mass-manufactured, which would lower the cost of using them to 8.2 cents per kilowatt-hour. That¡¯s not much more than the cost to buy energy from natural gas combined cycle plants at 6.5 cents per kilowatt-hour. However, fuel cells are even cheaper when the costs of distributing power are factored in; power plants lose energy as they transmit it through their power lines, and onsite fuel cells would not incur that cost. Therefore, the researchers estimate that the cost would drop to just 5.3 cents per kilowatt-hour; that¡¯s a clear win for retailers, hospitals, and multifamily housing.


    Fourth, power plants that are driven by fuel cells will increasingly provide an attractive alternative to other types of non-baseload power plants.


    According to a report in Power Engineering, Connecticut, Delaware, and California are now home to large-scale fuel-cell power plants.10 Beacon Falls, the largest fuel cell power plant on the planet, will be built in Connecticut in 2019 and will produce electricity for 60,000 homes. The entire plant will take up just eight acres, compared to 80 acres for a solar plant that would generate the same amount of power and would be less reliable.


    References
    1. The New York Times, April 7, 2016, ¡°Tesla¡¯s Model 3 Already Has 325,000 Preorders,¡± by Bill Vlasic. ¨Ï 2016 The New York Times Company. All rights reserved.

    http://www.nytimes.com/2016/04/08/business/teslas-model-3-already-has-325000-prospective-owners.html


    2. Business Insider, January 6, 2016, ¡°Electric Cars Are Cool But They¡¯re Still Only for a Small Set of People,¡± by Eugene Kim.   ¨Ï 2016 Business Insider Inc. All rights reserved.

    http://www.businessinsider.com/electric-cars-market-share-is-tiny-2016-1


    3. Digital Trends, March 27, 2016, ¡°While You¡¯re Charging Your EV, BMW Is Preparing for a Hydrogen Future,¡± by Ronan Glon. ¨Ï 2016 Designtechnica Corporation. All rights reserved.

    http://www.digitaltrends.com/cars/bmw-is-preparing-for-a-hydrogen-future/


    4. Ibid.


    5. Nature Communications, January 14, 2016, ¡°Nickel Supported on Nitrogen-Doped Carbon Nanotubes as Hydrogen Oxidation Reaction Catalyst in Alkaline Electrolyte,¡± by Yushan Yan, et al.   ¨Ï 2016 Macmillan Publishers Limited. All rights reserved.

    http://www.nature.com/ncomms/2016/160114/ncomms10141/full/ncomms10141.html


    6. Ibid.


    7. Scientific Reports, March 1, 2016, ¡°Micro Solid Oxide Fuel Cell Fabricated on Porous Stainless Steel: A New Strategy for Enhanced Thermal Cycling Ability,¡± by Gyeong Man Choi, et al. ¨Ï 2016 Macmillan Publishers Limited. All rights reserved.

    http://www.nature.com/articles/srep22443


    8. Science, September 18, 2015, Vol. 349, Iss. 6254, ¡°Readily Processed Protonic Ceramic Fuel Cells with High Performance at Low Temperatures,¡± by Ryan O¡¯Hayre, et al. ¨Ï 2015 American Association for the Advancement of Science. All rights reserved.

    http://science.sciencemag.org/content/349/6254/1321


    9. Fuel Cells, February 2015, Vol. 15, Iss. 1, ¡°The Case for Natural Gas Fueled Solid Oxide Fuel Cell Power Systems for Distributed Generation,¡± by L. Chick, M. Weimar, G. Whyatt, and M. Powell. ¨Ï 2015 John Wiley & Sons, Inc. All rights reserved.

    http://onlinelibrary.wiley.com/doi/10.1002/fuce.201400103/abstract/


    10. Power Engineering, February 2016, ¡°Fuel Cells to Play Important Role in Power Generation,¡± by Russell Ray. ¨Ï 2016 PenWell Corporation. All rights reserved.

    http://www.power-eng.com/blogs/power-points/2016/02/fuel_cells_to_playi.html