Electricity generation from renewables increased 29%, from 64.7TWh to a UK record of 83.3TWh.
Figures from the UK's Department of Energy and Climate Change (Decc) show production of wind energy grew 26% year-on-year, as solar (86%) and bioenergy (28%) also grew.
Generation from onshore wind rose by 24%, from 18.6TWh in 2014 to 23TWh last year, while offshore wind generation increased by 30%, from 13.4TWh in 2014 to 17.4TWh.
The increase is due to a combination of higher wind speeds compared with 2014 and increased capacity, particularly for offshore wind, Decc said.
Decc's figures also show energy prices have fallen 1.4% due to falling demand and lower energy costs.
RenewableUK deputy chief executive Maf Smith said: "Putting the consumer first means putting renewables first. As old coal turns off, renewables is quietly taking its place, delivering energy security and value for money. It makes more sense than ever to fully support and take advantage of our natural resources".
The UK added 1.008GW of new capacity in 2015, approximately half that of the previous year.
Scottish Renewables said generation from Scottish renewable energy sources produced 57% of Scotland's electricity needs, exceeding the 50% target set by ministers.
However, Scottish Renewables director of policy Jenny Hogan warned the country may miss its 100% by 2020 target due to UK policy uncertainty.
"Despite having enough projects in the pipeline, recent changes to government support and hold ups in the consenting process for offshore wind farms have set us on a path to fall short of the 2020 target," Hogan said.