The Green Wombat is blogging from Australia this week. On Monday I spent the day at the government-funded Commonwealth Scientific and Industrial Research Organisation’s Energy Centre, where I met with scientists developing a solar hydrogen technology that produces "solar gas" that can be carried through pipelines. The technology also can produce pure hydrogen that could be used in fuel cell vehicles. The big upside: solar energy can be "bottled," allowing it to be stored and transported. The downside: there are greenhouse gas emissions associated with the process.
CSIRO, with private partner Solar Heat and Power, has built an 85-foot (26 meters) solar tower at the Energy Centre in Newcastle, the coal capital of Australia located about a 100 miles north of Sydney. A field of 200 small mirrors tracks the sun and concentrates 500 kilowatts of solar energy on a receiver mounted on the tower. The solar rays superheat a reactor containing natural gas and water and the resulting chemical reaction produces a solar gas with about 26 percent more energy than natural gas. Because natural gas is used, any pure hydrogen produced from the solar tower would have greenhouse gas emissions as a byproduct. But there would be a 30 percent drop in emissions over conventional methods of making hydrogen from natural gas.
"One idea is that you could put the solar tower on the roof of a car park or shopping center and use it a hydrogen fueling station," says John Wright, director of CSIRO’s Energy Transformed program. And because Australia’s sunniest regions also tend to be sites of natural gas production, solar towers could be built next to pipelines.
The reactor will be installed on the tower next week but CSIRO
demonstrated the technology works in a reactor that was attached to a solar concentrator dish.
Anne Gerd Imenes, a Norwegian scientist working on the solar hydrogen
tower, said the cost of the dish made mass production prohibitive. So
CSIRO switched to a heliostat field to generate solar energy, taking a
Home Depot approach that uses off-the-shelf components. The solar
array? Bathroom mirrors glued on to steel frames.
Wright stresses that solar gas is a transitional technology in the
experimental phase. Still, with the Australian government’s
announcement this week that it will consider creating a carbon trading
market, interest in technologies that can reduce the global warming
effects from Australia’s heavy reliance on fossil fuels is sure to make
solar hydrogen a potentially attractive option.
Solar hydrogen is just one of several cutting-edge technologies
being developed at CSIRO’s Energy Centre with a view of being spun off
or licensed to startups or other companies. Stay tuned to the wombat
for further posts this week on what’s up with green tech Down Under.
Green Wombat 
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