At a factory in Finland, the "farmers of the future" are making food protein by feeding a microbe nothing but air and electricity, proving that protein can be produced away from traditional agriculture. "We want to tackle this problem of land use," says Pasi Vainikka, CEO of Solar Foods, "and replace, nutritionally, animals". Moving forward, cellular agriculture is increasingly seen as a green alternative to livestock farming, a major source of greenhouse gas emissions, the primary cause of global warming. IMAGES AND SOUNDBITES