The Liberal Democrats are aiming to stimulate at least £100 billion of private investment in the UK’s renewable energy infrastructure and want a third of the UK’s energy demand to be met from renewable sources by 2020.

The party has set the targets in its 2015 election manifesto, launched today by leader Nick Clegg at an event in south London.

The document outlines the party’s five “green laws” focused on improving the UK’s commitment to the environment with energy policy playing a central theme.

Clegg stated that his party had been instrumental in the trebling of renewable energy generation recorded since the current coalition assumed power in 2010 and outlined a number of ambitious targets for the adoption of and investment in renewable technologies.

The party has worked with the Committee for Climate Change (CCC) to establish a decarbonisation target for the power sector of 50-100g per kWh by 2030, and the party also aims to work towards a “Zero Carbon Britain” status – to be monitored and audited by the CCC – by 2050.

To achieve the decarbonisation figure the Lib Dems are targeting to generate 60% of the UK’s power demand from renewable sources by 2030, triggered by giving the Green Investment Bank full borrowing powers to boost investment in low-carbon technologies and complement the £100 billion private investment it intends to stimulate.

Also included in the manifesto is an expression of support for energy storage and various other energy efficiency technologies, and an abolishment of unabated coal energy plants by 2025.

The Lib Dems are the fourth major party to unveil their manifesto this week, following Labour on Monday and both the Greens and the Conservatives yesterday morning.

With UKIP set to follow later today, all parties appear split on energy policy and the support offered to solar and other renewable energy sources.