Hybrid solar /natural gas plant concept ready to yield steady energy output

solar gas reactor

Greentech Lead America:  While solar energy relies on other fuels for power generation, the reverse could also become true in the near future, reveals the latest research from Pacific Northwest National Laboratory in Richland, Wash.

Researchers at Pacific Northwest National Laboratory are preparing to test a new way that uses solar power to generate electricity from natural gas, according to this New York Times piece.  The process uses sun’s heat to release the energy content in natural gas.

The advantage of this hybrid solar/gas plant is that it can supply steady levels of electricity as opposed to other solar technologies that are unable to yield steady power output.

The concept is simple: While sun shines, you get solar electricity, and when it’s cloudy or dark, natural gas turbine supplies the same amount of electricity.

A natural gas molecule contains one carbon and four hydrogen atoms. Energy is required to break the bonds between the individual atoms and release hydrogen- the real fuel in natural gas.

The new system uses sun’s heat to break open the molecules of natural gas and water and reshuffle them to get something that burns better: carbon monoxide and pure hydrogen. The result also has byproduct- carbon dioxide, but in traces.

The process could cut the consumption of natural gas – and the greenhouse gases emitted – by 20 percent, researchers claim.

“We can reduce carbon dioxide emissions, and the consumer doesn’t get hit,” said Robert Wegeng, the researcher in charge of the project.

The system works wherever solar energy is available, but it is more valuable in places where natural gas is relatively expensive- for example in countries like Japan, or where an energy company is incentivized for producing less carbon dioxide.

The project has procured $4.5 million financing from federal stimulus fund. The cost of the technology is yet to be established. The process is also several steps away from commercial availability.

The highlight of Pacific Northwest design is that it relies on sunlight that is abundantly available on earth. Solar energy is trapped using parabolic mirrors. It can heat water and natural gas to700 degrees Celsius.

Researchers have also introduced a second innovation as part of this project. Before the synthesis gas is sent to the turbine for burning, heat is extracted from it. That heat can be sent back to the chemical reactor which can again be used for the synthesis of the new gas mixture, thus improving the efficiency of the entire process.

The cost benefits of the project as revealed by Pacific Northwest National Laboratory are: “If the system starts with one million B.T.U.’s of natural gas, the standard unit for pricing, then the synthesis gas has a value of about 1.25 million B.T.U.’s That means turning $4 of gas into $5.”

Photo courtesy: Pacific Northwest National Laboratory