More electricity has been generated from solar in the UK in a full day compared to coal for the first time according to analysis from Carbon Brief.
The UK's solar panels produced an estimated 29GWh of electricity on 9 April, beating the 21GWh generated from coal and providing 4% of the country's usage. Sheffield Solar, a research project at the University of Sheffield supported by National Grid uses data from over 500 sites to estimate the current half hourly generation from PV systems in the UK, showed that Carbon Brief's findings were repeated on the following day when 39GWh was reportedly generated.
The National Grid is unable to monitor real time figures for solar generation as this energy is not metered centrally. Carbon Brief compared data from Sheffield Solar and Gridwatch to reach its findings.
Despite representing a first for the UK's energy mix, Carbon Brief pointed out that this was a "largely symbolic" milestone as solar output has already regularly topped coal during the middle of the day. However, it is expected that this change in usage will become more prominent going into the summer months as energy consumption decreases.
High levels of solar generation have already continued since 9 April, with aggregated daily figures from Sheffield Solar showing 38GWh was generated from PV just yesterday (13 April). According to Aldous Everard, engineering manager for the Sheffield Solar Microgen Database, this trend is set to continue throughout the coming months.
Speaking to sister publication Solar Power Portal earlier today, he said: "Generation from solar will increase into the summer because there's more sunshine but also there were a lot of installations done in the back end of last year and the beginning of this year as a result of the feed-in tariff cuts and the price reductions solar has seen.
"As a result we will see an increase over last years generation from solar and, as there is usually a decrease in overall energy use during summer, solar is likely to provide a greater proportion of the energy mix during those months."
It has yet to surpass the fossil fuel across a full week or longer but data from 9 April puts on display the changing energy mix of the UK.
While the huge surge in solar has been partly attributed to it overtaking coal, the ongoing shift away from the fossil fuel has been deemed to be the main cause. UK coal use has fallen considerably in recent years, culminating in energy minister Amber Rudd's pledge to phase it out by 2025.
In contrast, recent analysis by Finlay Colville, head of intelligence at Solar Media showed solar deployment has grown to over 10GW in the UK in a short space of time, generating 2.2% of the UK's electricity in 2015 compared to almost 0% in 2011. Due to recent cuts to government subsidy across the board, a number of large scale sites and domestic PV systems were rushed to completion earlier this year.
This added significant amounts of new capacity to the grid and while reduced subsides are likely to see deployment slow, UK solar is still expected to increase throughout the year as the last large projects come online, the commercial rooftop sector continues to take off and wider use of PPAs is adopted.
This means solar will continue to become a more important part of the UK energy mix, particularly as the growing generation being supplied to the grid could replace the reduced power being supplied by coal.
Leonie Greene, head of external affairs at the UK's Solar Trade Association said: "Solar is highly reliable. It can be deployed rapidly and it can be accurately forecast. Analysts expect solar will attract a third of all energy investments globally until 2040, so it is set to play a major role in tackling climate change and delivering clean power.
"It is also one of the cheapest major renewables and the most popular with the British public, so why the UK government has stepped back from supporting this winning technology is difficult to understand. Current policy needs an urgent rethink if we are serious about saving consumers money and transforming our power system at the pace climate change demands."