The future of low-carbon energy in the UK became a little clearer on Tuesday when a new player entered the nuclear race and the government published a shortlist of four potential carbon capture and storage projects that will compete for funding.

The Japanese industrial company Hitachi has agreed to buy the nuclear consortium Horizon, a former project of the German utilities RWE and E.ON, which they put up for sale when they decided to bow out of UK nuclear energy in March.

Hitachi, which faces a nuclear shutdown in its home market after the Fukushima incident last year, will pay £700m and hopes to construct up to four nuclear reactors across the country. Horizon plans new reactors at Wylfa on Anglesey, north Wales, and Oldbury in Gloucestershire.

One of the world's leading naturalists has accused US politicians of ducking the issue of climate change because of the economic cost of tackling it and warned that it would take a terrible example of extreme weather to wake people up to the dangers of global warming.

Speaking just days after the subject of climate change failed to get a mention in the US presidential debates for the first time in 24 years, Sir David Attenborough told the Guardian: "[It] does worry me that most powerful nation in the world, North America, denies what the rest of us can see very clearly [on climate change]. I don't know what you do about that. It's easier to deny."

Coal is enjoying a renaissance, with the highest consumption of the fuel since the late 1960s. The unexpected development threatens to put climate change targets out of reach – and much of the reason is the rise of a supposedly "green" fuel, natural gas.

The controversial use of shale gas in the US, where it now makes up a quarter of electricity generation, has brought down carbon emissions there – but the greenhouse gases have simply been exported elsewhere, meaning no net gain for the planet, research by the Guardian and other sources has found.

The European Commission has launched an investigation into the UK government's approval of a £1bn gas-fired power station in Pembrokeshire following complaints by environmental campaigners.

RWE npower's 2GW Pembroke power station opened last month and is thought to be the largest of its type in Europe, capable of powering 3.5 million homes.

But a complaint by Friends of the Earth Cymru to Brussels has resulted in officials this week writing to the Department of Energy and Climate Change (DECC) asking it to clarify the impact of the power plant on surrounding coastal water.