President Barack Obama is about to announce the first US national fuel and emission limits for vehicles, including a fuel efficiency standard of 35.5 miles per gallon, that should see new models in 2016 made some 30 percent cleaner and more efficient than this year's crop.  

Executives from the 40 largest cities in the world, meeting in Seoul, have been urged by former US President Bill Clinton to act swiftly to reduce their emissions. Globally, cities occupy just two percent of the Earth's surface but house more than half its population and produce over two-thirds of all greenhouse gases. 

Here's another reason exploiting Canadian tar sands is not a good idea: oil sands emit between 5 and 15 percent more CO2 than average crude over the "well-to-wheels" lifetime analysis of the fuel.

Bioplastics made from waste that can be broken down into biofuel after use are a step closer to being commercially viable, new research presented at the 109th General Meeting of the American Society for Microbiology suggests - so long as some really efficient enzymes can be found.

Smart power grids are suddenly all the rage, with the European Union embarking on an EU-wide roll-out of smart meters for homes and businesses that could reduce energy use by 10 percent by 2020. Stephen Cunningham, CEO of the world's largest smart meter manufacturer, gives a lowdown on the technology and Europe's plan in this week's BBC "Green Room" comment.

Speaking of smart grids, the US Department of Energy has upped the individual project funding for smart grid initiatives from $20 to $200 million, which should see more large-scale projects undertaken.  

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