A key feature of cities around the world, underground public transport systems are just waiting to be made more sustainable. Researchers in Switzerland have just conducted a breakthrough study - on the back of decades of research - which could see cities harnessing the warmth from metro tunnels to heat local homes. Read on

A promising energy storage technology is being developed in Alzenau, Bavaria: Organic redox flow batteries. The concept, which derives from the biology of the human brain, could revolutionise mass power production. Read on

So-called "blue energy" has previously been branded too expensive for practical use. However, a new process - with no moving parts - could see its start-up costs plummet. Read on

A new energy storage system - consisting of huge quantities of rocks - is being tested in the Port of Hamburg. Read on

Swedish startup Enjay has developed a way to clean up the catering industry's greasy carbon footprint - by capturing restaurants' dirty waste heat and turning it into usable energy. Read on

On the African continent, the lack of eco-friendly transportation is being tackled by innovators who are tapping into the region's abundance of solar power. In Jacqueville, a small beach town on the Ivory Coast, the latest arrival is taxis fuelled by the power of the sun. Read on

A group of collaborators at MIT have come up with a remote assessment platform for rooftop solar that allows any community in the world to discover - and exploit - their underlying solar resource potential. Read on

There may be more to eggs than meets the eye. German researchers have just managed to transform eggshell biowaste into a rechargeable battery - in what looks to be a world first. Read on

Uganda's startup scene is booming, but all too often, the benefits of new innovations don't make it beyond the nation's capital. The non-profit ENVenture is working to develop inclusion strategies for remote areas - ensuring that clean energy solutions are available wherever they are needed. Our RESET writer in Uganda visited them to find out more. Read on