Solar capacity in the UK could reach 18GW by 2020, and could soar to even higher levels if policy support for other technologies is diverted to solar in the wake of policy changes according to the latest Future Energy Scenarios report issued by the National Grid.

This year’s edition of the study, published on Wednesday, predicts the deployment of energy generation technologies depending on various economic and policy factors and determines what the risks to the National Grid might be.

Both the ‘no progression’ and ‘slow progression’ scenarios paint a tale of minimal uptake all the way into the 2030s with little support from government and a tough economic climate, while ‘gone green’ and ‘consumer power’ scenarios include continued support for renewable technologies, accelerating their adoption.

Under the consumer power scenario solar PV capacity could reach as high as 18GW by 2020, slightly missing former energy and climate change secretary Greg Barker’s ambition of 20GW by 2020, however the difference between that and the bleakest scenario of no progression is stark, with National Grid projecting just 8.6GW – a minute increase over current expected capacity as of Q1 2015.

By 2030 the consumer power scenario predicts solar capacity could have topped 29GW, a substantial increase over other scenarios which the National Grid said would be typified by favourable economical conditions promoting research and development of new technologies, coupled with a strong decarbonisation effort in the UK.

If the consumer power scenario is to ring true National Grid forecast 46% of energy generation demand in the UK could be met by solar PV and wind by 2035, but again the no progress model forecasts that just 11.3GW of solar capacity could be installed in the UK by 2030 if conditions are unfavourable.

Simon Booth, Managing Director, REI says “lots of facts and figures in this article, but the underlying spirit is that solar will meet a high percentage of the UK’s energy demands over the coming decades”.