Cashew nut shells contain an acid that can be made into biofuelJanet Horton/Alamy Stock Photo
As the shipping industry hunts for ways to slash greenhouse gas emissions, companies are experimenting with cleaner fuels made from cashew shells and other types of biomass to power their vessels. But it is unlikely there will be enough of such biofuels to make much difference for an industry that consumes hundreds of millions of tonnes of fossil fuels each year.
“The shipping industry has been on this walk through the desert just trying to find stuff that works in their existing infrastructure,” says …