Tidal lagoons could be more cost-effective over 60 years than other forms of power generation, according to a review for government by former energy minister Charles Hendry, reports the Financial Times. The review backs what it calls a “pathfinder” scheme proposed for Swansea Bay in south Wales, reports the Guardian. Hendry urged the government to “stop dithering” and push ahead with the scheme, reports the Press Association. Hendry says tidal lagoons can play a “cost effective role”, reports Reuters, while a Bloomberg headline says tidal power “may be cheaper than Hinkley”. In a blog republished by Business Green, Richard Howard of thinktank Policy Exchange says the lagoon would be “folly”. He says the firm behind the scheme has “tweaked” financial estimates that “obfuscate the true cost of the project”. The Financial Times Lex column says that while the pilot may look expensive, it “should go ahead regardless”. The project is “very expensive” and limited funds would be better spent elsewhere, according to an unnamed “Whitehall source” quoted by the Times. The Independent Mail Online and Business Green have the story.

Investment in clean energy worldwide fell by 18% to $288bn in 2016, reports Reuters, covering new research from Bloomberg New Energy Finance. Sharp falls in unit prices for renewables and less spending in China and Japan were behind the fall, Reuters says. Despite the lower spending, wind and solar capacity increased by 19%, reports Bloomberg. The fall in spending is the biggest one-year drop recorded, reports the Financial Times, after record spending in 2015. It notes that a record 70 gigawatts (GW) of solar capacity was built in 2016, up from 56GW in 2015. Climate Home and Business Green also have the news.

Putting an immediate end to new coal-fired power stations in southeast Asia could save around 50,000 lives a year by 2030, reports Bloomberg, covering a study by Harvard University and Greenpeace International. Currently planned or under construction coal plants could raise annual air pollution deaths linked to coal from 20,000 to 70,000, the study says.

National Grid, which operates the electricity network across much of the UK, will be restructured under a deal proposed by regulator Ofgem, report the Financial Times and others. The company had faced calls for break up because it not only runs the grid but also owns some power infrastructure, creating potential for conflict of interest. The move to create a legally separate entity responsible for balancing grid supply and demand will help create a more proactive, flexible electricity system reports the Telegraph. The Times and Reuters also have the story.

Sales of electric vehicles increased 60% in January to November 2016, reports Reuters, reaching 402,000 vehicles. It says China wants five million plug-in cars on its roads by 2020 and notes that more electric cars are sold in the country than in the rest of the world combined. Most sales are cheaper local models, with foreign firms only able to access subsidies via joint ventures.

Global economic output will fall as the world warms, write Brian Deese and Jason Furman, advisers to president Obama. Losses could reach nearly 4.5% of global GDP by 2100, they say, but “most of these damages can be avoided with smart policy”. If global emissions are reduced to net zero by 2080, losses would be reduced to less than 1% of global GDP, whereas failing to invest in climate mitigation “could leave the global economy, and the US economy, worse off in the future”. These estimates are uncertain and may be conservative, they note, since they do not account for damages that are hard to value or impacts that are hard to model. They conclude: “Countries must weigh the costs of policy action against estimates of avoided climate damages…We should be clear-eyed about the fact that effective action is possible, and that the economic and fiscal costs of inaction are steep.”

A new report from the US National Academy of Sciences recommends “major updates” to the way government agencies view the costs of future climate change, explains Chelsea Harvey in the Washington Post. The incoming Trump administration appears to be seeking to downplay or do away with the so-called social cost of carbon measure, she says. But the new report could have the opposite effect, Harvey writes: “[Its suggestions] could help address growing scientific concern that we’re underestimating the damages global warming will cause.”

Those that argue the £1.3bn cost of the proposed Swansea Bay tidal lagoon would be better spent on alternative technologies or energy efficiency “posit a false choice”, says a Time editorial. Britain’s power consumption is already falling, it notes, and there is “an opportunity to refashion the country’s power supply to make it cleaner, cheaper and more dependable than ever. The clear message of the Hendry report is that tidal power should be a part of this supply”.

By 2100, the projected increase in heat stress in China could cause an average yield reduction of −7.1% and −17.5% for winter wheat and spring wheat, respectively, according to new research. While it’s possible the losses can be fully compensated by CO2 fertilisation, the authors urge great caution against assuming this, since crop models don’t yet fully capture the decrease in this effect over time and other factors that may limit growth. Wheat is one of the two major cereals consumed in China, with about 60% of the population eating the grain daily.

A new study takes a fresh look at the practice of fingerprinting the human influence on extreme weather events, commonly termed “event attribution.” Where lack of data and limits to computer power necessitate the use of atmosphere/land-only climate models, this can lead to overconfidence in the estimate of human influence if the event in question is a function of the ocean state, say the authors. Using case studies of the northwest coast of South America and northern-central Siberia, the study is a guide to where and when attribution researchers should be concerned about the use of atmosphere-only simulations.