Increasing grid penetration of intermittent renewable power from wind and solar is creating challenges for the power industry. There are times when generation from these intermittent sources needs to be constrained due to power transmission capacity limits, and times when fossil fuel power plant are required to rapidly compensate for large power fluctuations, for example clouds pass over a solar field or the wind stops blowing.
There have been many proposals, and some actual projects, to store surplus power from intermittent renewable power in some form or other for later use: Batteries, Compressed Air Energy Storage (CAES), Liquid Air Energy Storage (LAES), heat storage and Hydrogen being the main alternatives considered. These technologies will allow power generation during low periods of wind and solar power, using separate discrete power generation plant with specifically designed generator sets. But these systems are time-limited so at some point, if intermittent renewable power generation does not return to its previous high levels, fossil fuel power generation, usually from a large centralized power plant, will be required to ensure security of supplies. The overall complexity of such a solution to ensure secure power supplies leads to high capital costs, power transmission issues and potentially increased carbon emissions to atmosphere from the need to keep fossil fuel plant operating at low loads to ensure rapid response.
One possible solution is to combine intermittent renewables and energy storage technologies with fast responding, flexible natural gas-fired gas turbines to create a reliable, secure, low carbon, decentralized power plant. This paper considers some hybrid power plant designs that could combine storage technologies and gas turbines in a single location to maximize clean energy production and reduce CO2 emissions while still providing secure supplies, but with the flexibility that today’s grid operators require.