Q4 2019: Power system records

by Dr Iain Staffell – Imperial College London

2019 saw all clean electricity sources break their previous records for annual production. 

For wind, solar and biomass, these were all-time highs; for nuclear, it was the lowest output recorded this century. Wind supplied more than a fifth of Britain’s electricity for the first time, while coal fell to a new low of just 2%. 2019 was also the first year where Britain’s electricity averaged below 200 grams of CO2 per kWh.

On the 8th of December, wind supplied a record 43% of demand through the day, and total generation from low-carbon sources exceeded 30 GW for the first time ever. Overproduction and constraints in the transmission system led to wholesale prices reaching a new low of –£73 per MWh, and the first ever day with a negative average power price. Just two days later, wind broke its instantaneous record, surpassing 16 GW output for the first time ever.

1: Note that Britain has no inter-seasonal electricity storage, so we only report on half-hourly and daily records. Elexon and National Grid only report the output of large pumped hydro storage plants. The operation of battery, flywheel and other storage sites is not publicly available.