Splitting Water to Store Solar Energy

MIT professor Daniel Nocera worked on a catalyst that could break water molecules to store energy. To give his dreams a better shape he started a company named “Sun Catalytix”, backed by Polaris Ventures. Seeing the energy crisis he started working on generating cheaper sources of energy generation. Sun Catalytix is working on an advanced system that will use low-cost solar panels to produce hydrogen. This hydrogen will then be stored and used to produce electricity in a fuel cell.

The key to Sun Catalytix’s technology’s success will be the use of Cobalt Phosphate catalyst. Cobalt phosphate is more efficient at splitting water into hydrogen and oxygen than other catalysts. Its USP is this catalyst will work under ambient temperatures and with a wide range of water quality. The laboratory has got water samples from Charles River in Boston and it worked well. Many commercial electrolyzers are available in the market that split water to make hydrogen. But their main drawbacks are they are costly and they need lots of energy to run. But, Sun Catalytix is testing an electroylzer, built around the catalyst that can be produced using cheap PVC plastic. The crux of the matter is to exploit solar panels to power the electrolyzer to produce hydrogen. This hydrogen would be stored in tanks. Whenever the need arises, the stored hydrogen would be put into fuel cells. Only three litres of water a day could power a home, or even a fuel cell car. This technology can be very well used in developed countries that hold a record of high consumption of electricity. But if we consider the case of developing countries where people don’t have so much energy to use, there three litres of water would make a world of a difference. Three litres would fulfil the power needs of many people. This technology is moving really fast.

Sun Catalytix is already at the engineering prototype design stage. The job of scientist for the development is over, now only the role of engineering is left. The company is having massive engineering effort right now to commercialise the scientific concept. Within two years we can expect a working system with high capacity. Research is currently being done to minimize the size of the large-scale systems, just like what happened at the evolution of computers. But it seems difficult that shrinking of size will also shrink the costs of production, as the price of batteries has not come down in past few years now. For the full commercialization of this product common consumer might have to wait for eight or ten years. Before getting the technology into market many loose ends have to be tied like, developing system for hydrogen storage( which is a daunting task), have cheaper solar cells (shouldn’t take long) and cheaper fuels cells.( doesn’t seem to be happening as the cost of chemicals used has remain fixed which takes most of the cost of the fuel cells)

Saurabh Mehta

[Image courtesy: http://cleanlantern.files.wordpress.com/2009/04/mitsolarhydro.jpg]