We need to find a way to reduce waste, and the answer could be moving to a circular economy, which seeks to design out wastage by making use of byproducts and reusing materials. “The circular economy is an excellent way to deal with many of the major crises that we are facing,” says Anne Velenturf, a circular economy researcher at the University of Leeds. “Producing stuff takes a lot of energy, and if we make better use of our products then we also save much of the carbon embodied in them.”
Half of the world’s insulin comes from this factory in Kalundborg, Denmark, and its production relies on vast fermentation tanks full of yeast broth. Manufacturer Novo Nordisk passes its spent yeast slurry to Kalundborg Bioenergi to make biogas. “Any leftovers, you can put on the fields as fertilizer,” says Kalundborg Bioenergi CEO Erik Lundsgaard.
AeroFarms grows kale and lettuce in stacks in an old steel mill warehouse in Newark, New Jersey, planting seeds into cloth made from recycled plastic bottles and misting seedlings from the bottom up to save 95 per cent of water over field farming. Precision LED lighting uses only spectra relevant to plants to avoid wasting energy. But smart farming can only go so far: we bin a third of the food that we produce, some 1.3 billion tons a year, according to the UN. “Reducing production and consumption can limit the damage done to the environment,” says Velenturf.