Hybridizing fossil plants with solar thermal technology.
Charles W. Thurston is a Fortnightly contributor based in Sonoma County, Calif.
Several U.S. utilities are experimenting with hybrid concentrated solar thermal technology to boost generation at gas, coal, and even geothermal power plants. These projects are aimed at reducing fossil fuel consumption and carbon emissions, and to fulfill renewable portfolio mandates. As a result, concentrated thermal solar is emerging as a viable baseload or peaking-power option—as an add-on to an existing plant, or as part of a greenfield endeavor.
Adding a solar thermal plant to an existing generating facility can be more cost effective than adding a stand-alone solar photovoltaic (PV) plant. But new technology developments with solar thermal are helping to drive down costs even further. Heat storage capability and scalable modular design are two such development factors now being tested by utilities.
Since much of the connection, control room and power plant equipment at an existing generating facility can be shared by the solar addition, the cost of installing the solar equipment needed for a hybrid facility can be half or less of what would be required for a standalone solar unit, according to Hank Price, a director of technology at Abengoa Solar.