If you tuck into a piece of meat today, in whatever form it may be, there’s likely to be a long supply chain behind it that is mostly invisible. There’s the animal it came from, obviously. Behind that is the feed that reared that animal to full size, usually soy. Behind the feed is the fertilizer that was used to grow the crop. And behind the fertilizer is the natural gas that was a feedstock for the Haber-Bosch process.
All of these steps have a considerable environmental impact – there are the greenhouse gas emissions from fertilizer production and livestock, the pollution from fertilizer, and the land and water use for growing the feed. Wouldn’t it be great if you could cut out the middle of the process – the feed – and just produce a kind of fertilizer for animals?
A company called Calysta has developed a technology that does more or less that, using micro-organisms that feed on methane. The gas is piped into a fermentation tank and consumed by the micro-organisms, which multiply. They are then separated from the liquid growing medium, dried and pressed into pellets. These protein pellets, called FeedKind, are then added to animal feed or fish food for aquaculture.
There are a host of benefits to this. For starters, almost no land is required. Analysis by the Carbon Trust estimated that one of Calysta’s factories would save an area of land the size of Birmingham or Chicago – enough to feed a quarter of a million people.
Water is saved too. During the separation process, the water is spun out and goes back into the tank to be re-used. That yields a water saving of 77 to 98% when compared to soy production.
At the moment FeedKind is being produced for fish farming, where it replaces fish meal. That’s made from wild fish, so producing it through gas fermentation reduces pressure on global fish stocks.
Finally, there are a number of different sources for the methane needed to run the process. If it was run off biogas, landfill gas, or waste gases from industry, then we’d be able to file it as a low carbon process too.
The whole idea is new and pretty radical – but it’s not theoretical. The first plant producing feed from gas opened in Teeside last year, and it shipped its first four tonnes of feed last week. This is a technology to keep an eye on.