Complex sentence: The gas-fired station opened in 1991 and was the first CCGT power station to supply electricity to the United Kingdom's National Grid, but was mothballed in 2012 after a proposed biomass power station was cancelled.
Split into simpler sentences: The gas-fired station opened in 1991 and was the first CCGT power station to supply electricity to the United Kingdom's National Grid. It was mothballed in 2012 after a proposed biomass power station was cancelled.