Water is at the heart of many of the most serious ecological crises we face, including the biggest one of all: the climate emergency. Alok Jha shows how water itself may offer solutions to give us hope.

Alok witnesses nuclear fusion in action at an experimental reactor in England. Simple seawater provides the fuel for this futuristic technology that has the potential to solve the world’s energy problems and eliminate fossil fuel power generation.

Meanwhile chemist Fernando Romo walks us through the fascinating science of artificial photosynthesis, which allows humans to mimic plants, drawing carbon dioxide out of the atmosphere and storing energy in the process.

But water historian Terje Tvedt cautions that the more reliant human societies become on water technologies, the more vulnerable we make ourselves to changes in the water landscape. An innovative 3D mapping project by activist geographer Hindou Ibrahim shows how technology must be married to grassroots organising and political action if it is to break out of the lab and help secure our water future.

(Photo: Water droplets on a leaf. Credit: Getty Images)