Former Energy and Climate Change secretary and Liberal Democrat MP Ed Davey has landed three renewable energy advisory roles four months after his defeat in the general election.

Davey lost his seat as MP for Kingston and Surbiton to Conservative rival James Berry in a shock election result which saw an 18% swing in the vote. Davey’s position at DECC was in turn lost to Conservative MP Amber Rudd, and Davey had been out of the limelight until writing for The Guardian last week to question George Osborne’s policy cuts as “bonkers”.

Last week Davey was appointed chairman of community energy company Mongoose Energy, which is currently in the process of launching a community energy supply company.

Davey is to manage and provide advice to the company’s board of directors and said there was “great potential” for a huge increase in community energy projects across the UK.

“As secretary of state I was proud to launch Britain’s first ever community energy strategy and as chairman of Mongoose Energy I will be able to play a new role outside of government helping to shape the future of community energy in the UK,” he said.

But more contentiously, The Guardian reported on Tuesday that Davey is to also serve as a consultant for legal firm Herbert Smith Freehills, lawyers connected to the Hinkley Point C nuclear reactor and the Swansea Bay tidal lagoon, as well as a separate consultancy deal with Macquarie Bank to provide advice on rooftop solar projects the investment bank is involved in.

The Guardian has said Davey was granted Cabinet Office approval to start work with Herbert Smith on the basis he advises on renewable energy projects and not Swansea Bay or Hinkley.