If adopted, the plan is expected to result in 2.1 million solar homes, 24,000 commercial rooftop and community schemes, 2,300 solar farms and about 57,000 jobs in solar and its supply chains.
Under its Solar Independence Plan for Britain report, the STA said the move would in 2020 only cost households about £13 a year.
The report recommends six policy changes including adjusting the feed-in tariffs (FiTs) to allow more growth and aiming for zero subsidy by 2020,
It is also seeking to safeguard the Renewables Obligation support regime for larger rooftops and smaller solar farms until March 2017.
The report recommends to enable solar a fairer share of the levy control Framework and adapt Contracts for Difference to benefit solar and small businesses.
It suggests to incentivise the incorporation of solar into new build houses and offices as well as address grid constraints.
STA CEO Paul Barwell said: "Our goal is to secure a strong British solar industry that can beat fossil fuels on price without subsidy, as quickly as possible.
"Our Solar Independence Plan shows that a carefully structured policy framework would enable Government to greatly increase its ambitions for the UK solar industry for surprisingly little additional cost.
"The global solar market is estimated to be worth $5trillion to 2035 [2] and we want to see British solar firms winning internationally, as well as at home."
Image: The UK government has been urged to adopt a higher solar ambition scenario with a target of 25GW by 2020. Photo: courtesy of graur codrin/FreeDigitalPhotos.net.
