Renewable energy can be stored as gas
Breakthroughs in the USA and Germany-Austria enable surplus renewable energy such as that produced by wind farms or waves on stormy nights, to be economically turned into hydrogen or methane.
The breakthrough in the USA is the discovery of a catalyst about one seventieth the cost of platinum that enables the efficient electrolysis of ordinary sea or river water to produce hydrogen without the need to acidify it or add some other electrolyte first.
The new catalyst is a molybdenum-oxo metal complex, designated (PY5Me2) Mo-oxo which has been discovered by Hemamala Karunadasa, Christopher Chang and Jeffrey Long. All three hold joint appointments with Berkeley Laboratory's Chemical Science Division and University College Berkeley's chemistry department.
Long said, "This metal-oxo complex represents a distinct molecular motif for reduction catalysis that has high activity and stability in water. We are now focused on modifying the PY5Me ligand portion of the complex and investigating other metal complexes based on similar ligand platforms to further facilitate electrical charge-driven as well as light-driven catalytic processes. Our particular emphasis is on chemistry relevant to sustainable energy cycles."
The Austro-German breakthrough is to then react hydrogen, which is difficult to store and transport, with carbon dioxide. The plan is to generate methane that can be injected into the already existing natural gas storage and distribution system, or compressed and used as an automotive fuel, presently powering millions of vehicles in Pakistan and India.
The process was developed by the Center for Solar Energy and Hydrogen Research Baden-Württemberg in cooperation with the Fraunhofer Institute for Wind Energy and Energy System Technology. Solar Fuel Technology, an Austrian partner company, is responsible for industrial implementation. A demonstration system is already said to operating successfully in Stuttgart. A system with a capacity of 10MW is to be launched in 2012.