Great Britain’s renewable energy auction has secured enough new clean electricity projects to power 11m UK homes after the Labour government made record funding available to suppliers.

The £1.5bn auction will support a total of 131 new projects including windfarms, solar farms and tidal power projects after the new government increased the amount of funding available to seven times the sums offered last year.

The sixth auction of its kind is expected to bring forward a deluge of new investment and jobs by giving developers a guaranteed price for each unit of clean electricity they generate, which is paid for by energy bills.

Ed Miliband, the energy secretary, said: “Today we have now achieved a record-setting round for enough renewable power for 11m homes, essential to give energy security to families across the country. It is another significant step forward in our mission for clean power by 2030 – bringing Britain energy independence and lower bills for good.

“These results show that together, this government and the energy industry are securing investment into our country. This auction has produced a record number of solar projects bolstering our mission for a solar revolution, we have powered forward with onshore wind, secured the largest commercial floating offshore wind project in the world and got the offshore industry back on its feet,” Miliband said.

The bulk of the funding was awarded to new offshore windfarms in UK waters. This could lead to enough new offshore windfarms to increase the UK’s capacity by 5GW, or enough clean electricity to power over 3m UK homes before the end of the decade.

However, the auction has secured only half the offshore wind capacity needed every year if the government hopes to meet its green energy targets, according to Greenpeace. Ami McCarthy, Greenpeace UK’s political campaigner, said the government “needs to take a hard look at how this system is working”.

“5GW of offshore wind is of course welcome, but it is only about half of what is required each year to meet the government’s 2030 target. The last renewables contract auction was a catastrophic failure, and in fact the biggest disaster for clean energy in almost a decade. Because of this, the new government has an uphill battle,” McCarthy added.

The auction also awarded contracts to about 90 new solar farms with a total capacity of 3.3GW and 20 new onshore windfarms with a total capacity of almost 1GW. Tidal power developers secured contracts for six new projects, and the world’s largest planned floating offshore windfarm also clinched a contract.

The success of the closely watched industry auction was considered crucial if the new government hoped to achieve its election pledge to double onshore wind, triple solar power and quadruple offshore wind by 2030.

Labour took action weeks after winning the July general election to increase the value of the auction by 50% compared with the funds promised by Conservative ministers. The move aimed to reignite investment in the UK’s clean energy industry after the previous government failed to award a single new offshore wind contract last year or remove the blocks on onshore wind.