Despite it still being early in the year, Saturday and Sunday the 25th and 26th of March saw very high levels of solar generation in the UK, with this flattening the demand shape for coal and gas plants over this weekend period, aside from the evening peaks.

Energy consultancy EnAppSys told Power Engineering International that, based upon forecasted levels of solar power generation, solar provided almost 30 per cent of power at its peak; with 45 per cent of power coming from renewable sources during this peak period in the middle of the day. Accounting for levels of nuclear generation, 64 per cent of power generation during this peak came from clean sources, with 29 per cent coming from gas plants and less than 1 per cent from coal-fired power stations.

“The growth of solar certainly creates challenges for the market but power prices remained at typical levels for a spring weekend; with no sign that the market faced undue challenges meeting the evening peak, despite the flattening of demand in the middle of the day,” Paul Verrill, director, EnAppSys, told Power Engineering International.

“Spring is often characterised by a highly changeable market, driven by large shifts in levels of wind and solar generation and while the weekend saw low levels of wind generation, the impact that solar can now have was highly apparent over this weekend period.”
Solar power and sun
The consultancy said that as renewable levels grow in size, a long-term requirement for storage looks highly likely within the market, but without significant price volatility, the immediate market for shifting large volumes of renewables is not apparent yet without storage projects being given additional support. 

“Until that point comes, gas-fired plants are learning how to become more flexible in their operational activity and to fit in around this increasingly changeable market, managing the generation requirements and ensuring that increases or decreases in power output are achieved as cost-effectively as possible. As time goes by achieving this goal becomes more challenging, creating increased opportunities for OCGTs, OCGT-conversions and small flexible generators, whilst decreasing the typical run hours being achieved across the wider market.”

Leonie Greene, head of external affairs at The Solar Trade Association, said it was a “landmark” achievement for UK solar.

“It proves just how much clean power is now being supplied locally by distribution-connected solar. This landmark clearly points the way towards the future strategic evolution needed on our networks. The next steps, which can’t come soon enough for the solar industry, are expediting the transition to an active DSO [Distribution System Operator] model and opening up markets including in network deferment, where storage has a huge role to play,” she said.

Verrill added that in the short term it is clear that the GB power market is decarbonising, and decarbonising quickly, ‘with coal having been pushed to the very margins of the market and with renewables continuing to hit new heights.’