By 2050 there will be another 2.5 billion people on the planet. How to feed them? Science's answer: a diet of algae, insects and meat grown in a lab

Sub-Saharan states need to move to renewable energy sources as $15bn in aid is outstripped by $18bn in oil imports, says IEA

OECD report says pollution will become biggest cause of premature death, killing an estimated 3.6 million people a year by 2050

Urban air pollution is set to become the biggest environmental cause of premature death in the coming decades, overtaking even such mass killers as poor sanitation and a lack of clean drinking water, according to a new report.

Bolivia has vast reserves of lithium, seen as the green energy fuel of the future, which it wants to exploit on its own. But the lithium is locked underneath a 10,000 sq km salt flat

Bolivia has more lithium than anywhere else in the world but its potential to fuel lithium-ion batteries for electric cars is in danger of failing.