Balancing the production and demand on electricity grids has been critical since the first grids. All the equipment and facilities connected to the grid require the voltage and frequency to be maintained within tight limits – in the UK this is 230 volts -6%, +10% and frequency within ±1% of 50Hz. As the public switch on or off appliances or businesses use machines, the electricity demand fluctuates, and the grid must respond accordingly.
Historically the grid was simple. Made up of a relatively small number of large power stations, the demand predictably followed the working day and the seasons. The National Grid control room would call the electricity generators and request that they ramp up or down, supplemented by fast-responding pumped hydro schemes. Similarly, they might call large electricity consumers and ask them to reduce their use in periods of high demand.
The grid has become far more complex and dynamic. Now comprised of the few large predictable mainly coal power stations it’s an increasing complex landscape of renewables generators – there are 1,336 solar farms alone in the UK. In addition to domestic electricity production the UK now has nine electrical interconnects to other countries, totalling 7.8GW capacity, which is nearly matched by grid storage batteries, with 7.4GW expected by the end of the year. Meanwhile, there are fewer of the large industries that created a stable baseload demand, with an increase in unpredictable demands such as heat pumps and vehicle charging.
... to continue reading you must be subscribed
