Possible Energy Solution:
Hydrogen-Fuel Discovery May Spawn Solar Power, MIT Study Says
By Jim Efstathiou Jr.
July 31 (Bloomberg) -- A new, cheaper way to store electricity to run air conditioners or vehicles promises to make solar power competitive with traditional generation, Massachusetts Institute of Technology researchers said.
The discovery might shatter the biggest barrier to widespread use of solar, namely that it's unavailable after dark, said Daniel Nocera, an MIT energy professor. The process uses non-toxic natural materials to convert sunlight into gases, as described in a paper today in the online version of Science.
Electricity produced from sun rays by photovoltaic cells costs about four times as much as power from conventional coal- fired generators. The higher expense of storing solar power in batteries has undercut its acceptance as a dependable source of renewable energy.
Cheaply storing energy from sun rays would mean ``you've answered everything,'' said Kevin Book, senior energy analyst for Friedman, Billings, Ramsey & Co., before the study was published. For solar power, ``It's the difference between being on the sidelines and being the quarterback,'' he said in an interview.
The breakthrough uses a relatively simple way to use electricity to produce oxygen and hydrogen from water, said Nocera, senior author of the paper. When the two gases later are recombined in a fuel cell they cause a chemical reaction that spins off electrons that are forced through a circuit, reproducing the electricity.
MIT's process might be integrated directly into solar panels used today at homes and businesses, provided more improvements are made, Nocera said.
Efficient Fuel Cells
Fuel cells first need to be made more efficient, and engineering problems must be resolved, before the new process can be commercially combined with solar devices, Nocera said.
``The reason photovoltaics have never penetrated the market is you can't store any energy from them,'' Nocera said in an interview. ``This is a basic science discovery. People are going to run with this because anybody can do it.''
Within 10 years, homes could be powered in daylight using solar cells, and at night by using fuel cells running on hydrogen and oxygen produced from surplus solar energy, Nocera said. The energy source eventually could eliminate the need for electricity to be supplied by power plants and delivered to homes over transmission lines, he predicted.
``This is a major discovery with enormous implications for the future,'' James Barber, the Ernst Chain Professor of Biochemistry at Imperial College London, said in a statement from MIT. ``It opens up the door for developing new technologies for energy production.''
Colbalt and Phosphate
Today's paper describes a way to release oxygen from water using a new catalyst of cobalt metal, phosphate and an electrode placed in water. When electricity is passed through the electrode, the cobalt and phosphate form a thin film on the electrode, and oxygen is produced.
The process mimics a plant's ability to turn light energy into chemical energy, Nocera said. The main difference is that plants produce a solid form of hydrogen and use most of the energy they manufacture to survive.
In performing what amounts to artificial photosynthesis, all the potential energy of water can be captured in the form of a fuel, like gasoline or natural gas, Nocera said. Fuels store energy more efficiently than do traditional batteries.
``Sunlight is the only renewable and carbon-neutral energy source of sufficient scale to replace fossil fuels and meet rising global energy demand,'' according to the paper. ``Of the possible storage methods, nature provides the blueprint for storing sunlight in the form of chemical fuels.''
Much of the project was funded by the Chesonis Family Foundation, which gave MIT $10 million in April to begin an initiative for large-scale deployment of solar energy within 10 years. Funding also came from the National Science Foundation.
``The hard part of this was getting the oxygen out'' of water, Nocera said. ``We were doing it in high school, but we weren't doing it efficiently, and we weren't doing it cheaply.''
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