Solar energy generation surged by around 153% over the last year in the UK, based on the most recent figures from the analyst company EnAppSys — with average daily electricity generation being around 1.37 gigawatts (GW) during the second quarter of 2015.

The new report also notes that, while solar photovoltaic (PV) generation accounts for only 4% of the UK’s electricity supply (as of the second quarter of 2015), that growth in the industry was already causing “oversupply” to the grid — thus contributing to negative market prices during some periods.

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The report follows this observation up with the statement that, owing to the intermittent nature of solar energy generation (as well as wind energy generation), coal and gas-fired power plants need to be better able to rapidly switch off when grid oversupply occurs.
The director of EnAppSys, Paul Verill, commented that gas + coal generators will have to become more flexible with the growth of solar PV generation.

Renewables are playing an increasingly important role in meeting Britain’s energy needs and as the contribution increases, it must be assumed that its impact on pricing and supply issues will continue to grow.

If the capacity and output of solar PV and other renewables continue to grow, conventional power generates such as CCGT and coal will have to be more flexible to avoid oversupplying the network and paying the penalty of negative power prices.

On that front, the second quarter of 2015 saw the UK receive roughly 20% of its electricity from renewable energy sources — as compared to 50% from gas + coal, 22% from nuclear energy facilities, and a further 8% from outside countries. Owing to seasonal variations (primarily with hydroelectric generation), the share held by renewables regularly goes a bit higher.