Labour leader Jeremy Corbyn claims his party’s plans for a “green industrial revolution” will transform society and create high-quality jobs.
Mr Corbyn restated Labour’s support for schemes such as a Swansea tidal lagoon ahead of a visit to Machynlleth, Powys.
He accused the UK government of a “failed approach” to climate change.
Mr Corbyn said Labour in power at Westminster would follow the Welsh Government’s lead on energy efficiency and in declaring a climate emergency.
Labour’s energy plans – outlined by Mr Corbyn at last year’s party conference – would also see the National Grid taken into public ownership and solar panels installed on nearly two million homes.
Speaking before a visit to the Centre for Alternative Technology on Friday, Mr Corbyn said: “The next Labour government will turn the Tories’ failed approach on its head with a green industrial revolution to tackle the climate emergency, create hundreds of thousands of good green jobs in every region and nation of our country and save millions of households money on their bills.”
He said Labour policies would “benefit working-class people by cutting energy bills, creating good jobs in new, green industries and fighting the climate emergency”.
Mr Corbyn also criticised the Conservatives and Liberal Democrats for the scrapping in 2013 of a homes insulation programme for England by the then coalition government.
He claimed the cancellation of the Warm Front scheme for poorer households had cost them a total of £3.7bn in potential savings on their bills while increasing emissions by the equivalent of an extra 8.6m cars.
Mr Corbyn said that by contrast, the Labour-led Welsh Government had spent more than £240m since 2011 to improve household energy efficiency through its Warm Homes scheme.
Following the Welsh Government’s declaration of a climate emergency in April, the Labour leader led a Commons debate on a similar call in May.
The proposal was approved without a vote to demonstrate the will of the Commons to declare a climate emergency, but did not legally compel the UK government to take any action.
Jane Dodds, the newly-elected Liberal Democrat MP for Brecon and Radnorshire, said she backed Mr Corbyn’s plans.
“We absolutely would back any proposals, any initiatives which would make sure the Swansea tidal lagoon is back in place, with the funding it deserves, as well as any other initiatives,” she said.
“The climate emergency is one of those things we cannot afford to be tribal about. So anything that any party puts forward, is really to be supported.”