The implications of embedded generation on the NGC transmission system

Since the restructuring and privatisation of the UK electricity supply industry, the principal method of power generation has undergone a shift from large conventional coal, oil and nuclear power stations to gas turbine based plant in combined cycle (CCGT) and combined heat and power (CHP) configurations. Whilst much of this new plant is connected to the National Grid Company (NGC) transmission system at 275 or 400 kV (station size ranging from around 300 MW to 2000 MW), an increasing trend in the connection of generation embedded within REC distribution networks has been observed (station size ranging from below 10 MW up to approx 350 MW). This paper addresses the effects that an increased volume of embedded generation could have on the planning and operation of the NGC transmission system