MIT’s press office saves humankind.
This lurid and misleading MIT press release claims a recent energy technology discovery is "revolutionary," has "enormous implications for the future prosperity of humankind," and is "nirvana." The New York Times and Los Angeles Times ignored the hype but gave the story so little space it was impossible to figure out what was discovered or why it might be useful. The MIT spin remained intact in several prominent blogs, with comments showing many were misled into thinking hydrogen will now be abundant and cheap. Here is my reporting with the context and probably more enthusiasm than the MIT discovery deserves.
Scientists at MIT have discovered an electrode and catalyst system with potential to reduce the cost and increase the efficiency of "electrolysis," the process in which hydrogen is generated from water by electricity. This discovery, first reported in Science on July 31, 2008, is being welcomed enthusiastically by proponents of a "hydrogen economy" to displace the "petroleum economy."
"Electrolysis" of water into hydrogen and oxygen has been practiced since about 1800 and is a common laboratory exercise in high school chemistry. When a direct current of sufficient voltage is applied to electrodes in water containing an electrolyte such as sodium sulfate, hydrogen gas forms bubbles and evolves from the cathode, and oxygen bubbles evolve from the anode. The choice of electrodes is quite important to the efficiency of the process and has been the focus of much research. Platinum makes a highly-efficient cathode, but all anode materials have been quite inefficient. As a result, only 50-80% of the electricity input is typically converted to potential energy in the produced hydrogen, the balance being wasted as heat. Wikipedia, Electrolysis of Water, downloaded 6 August 2008.
The MIT group has found that efficiency at the anode can be significantly improved by using an indium tin oxide electrode in a solution containing cobalt and phosphate ions, according to the online abstract in Science. This discovery has the potential to allow the design of electrolyzer equipment that wastes less of the electricity input than do currently available electrolyzers, and also to make the equipment itself less costly because cheaper indium and tin can be used in the anodes instead of platinum, which is the current default choice.
Developing a "hydrogen economy" is of interest to producers of electricity, especially the nuclear power industry and proponents of electricity from photovoltaics and concentrated solar thermal energy. If the electricity can be converted to hydrogen and stored with only minor losses, these sources of electrical power would be more versatile and/or more economical. Nuclear power plants could generate hydrogen at night when grid demand is low, and solar-generated electricity could be converted to hydrogen in the daytime and used at night. For example, the MIT press release suggests that the discovery makes it feasible for a single home or other isolated facility to supply all of its electricity needs around the clock without a connection to the grid.
Hydrogen is also being promoted as a replacement for petroleum products in highway transportation. Hydrogen presently has an advantage over battery-powered vehicles because hydrogen can be more quickly pumped into a vehicle's tanks at a filling station than a vehicle's batteries can be recharged with electricity. Hydrogen can be converted back to electricity in on-board fuel cells. However, in addition to the need to put in place a completely new distribution system, one of the main disadvantages of the hydrogen fuel cycle is that it wastes more of the original electrical energy and, therefore, is likely to be more expensive to operate than a battery-powered vehicle. The recent MIT announcement addresses one of the inefficiencies in the hydrogen fuel cycle, but there are others including the inefficiency of fuel cell electrodes in reconverting oxygen to water.
PS: This story doesn't change my view that hydrogen vehicles can't catch battery-powered vehicles.
Update on Friday, June 8, 2018 at 10:17AM by
Skeptic
The spinoff intended to commercialize the new catalyst is Sun Catalytix. A presentation by Prof. Nocera about its goals and progress is reported here. In early 2011, the company discovered that when certain substrates were coated with proprietary catalysts, immersed in water, and subject to solar radiation, there was direct evolution of hydrogen and water. This was dubbed the artificial leaf and led to an investment by Tata Group, reported here. In March 2013, Technology Review reported that Sun Catalytix had put on hold its "bold vision of enabling the hydrogen economy" (presumably meaning both the electrolysis and artificial leaf efforts) and had spent the last year and a half developing a flow battery for grid storage. In August 2014, the company was acquired by Lockheed Martin, which was interested in its flow battery technology.