FRETSGATE will develop a novel optical temperature sensor with the potential to reduce CO2 emissions from UK power generation by 1 million tonnes per annum (mtpa) through efficiency gains. Gas Turbines (GTs) for power generation produce 40% of UK electricity and 81mtpa of CO2. Combustion control is key to radically improving GT efficiency and reducing CO2 emissions, yet little high performance instrumentation is available for the harsh conditions. There is increasing interest in flexible fueling of GTs, including with hydrogen rich fuels from coal gasification, which bring issues with flashback instability and stall control, requiring fast sensor response times. These issues are currently addressed by running engines with wide safety margins leading to combustion not optimised for efficiency. FRETSGATE leverages the consortiums knowledge, skills and technology base to develop high speed temperature sensors for real time combustion monitoring at ?1200 degrees C.