In the latest issue of Pig World, AHDB knowledge transfer senior manager Ben Williams discusses the exciting potential of hydrogen technology for pig farms
I am a critic, not convinced of the ability of technology to deliver what we require. This is not the fault of the technology but the inability of policy, society and markets to provide a suitable ‘ecosystem’ in which that technology can deliver returns.
AHDB recently commissioned NFU Energy to produce an analysis of existing and emerging technologies in light of our buildings survey. The pork GrowSave report is a starting point for suggesting energy solutions UK producers may wish to invest in as the UK agriculture continues to drive towards net zero and face the increasingly rigorous demands of permitted agriculture.
Stalwart solutions – air scrubbers, heat exchangers, insulation and renewables – topped the discussion, but some different things, those exciting ‘what ifs?’, have also emerged, often already being trialled in the far corners of UK pig production.
One for me that needs to be explored is that of generating hydrogen from slurries, not because I believe we should switch the world to a hydrogen economy, but because it captures the true value of the pig – a circular economy.
Pigs, for me, are the great improver, they take ‘waste’ – by-products from other industries – and make them useful, as feed, bedding, and now their own ‘wastes’ may power their environment, the machinery that produces their and our feed and so on.
Hydrogen electrolysis is a commercially viable solution backed by research. Electrolysis of ammonia in waste water consumes just 1.55 kWh of electrical energy to produce 1 kg of hydrogen. When used as part of a fuel cell, 1 kg of hydrogen can produce 33 kWh of electrical energy.
If the electricity for electrolysis comes from renewables (wind and solar), there is no ‘direct’ release of CO2 in generating the hydrogen or burning of it for power. So what are the barriers to making the most of this seemingly abundant, clean (the waste product is water) and potentially valuable energy source?
Some UK pig farmers have used this method to produce hydrogen. Simply put, it’s worth circa £300,000 per year on a 500-sow unit (£20 per finished pig). It can also be part of a strategy to achieve zero emissions.
Using heat recovery with segregated air inlets via underground cooling ducts for all-year-round temperature stability, with harvested heat used to evaporate water from slurry, producing saleable pelleted fertiliser, means there is no need for a slurry store.
Hydrogen technology is not new – hydrogen has been extracted from ammonia sourced from fertiliser production for years – but it could be fossil-fuel free. There is still work to do on changes needed to government policy on local energy generation and making sure the technology is accessible to producers and adds up to a clearly defined return on investment.
The future is now. AHDB will continue to support producers to drive towards net zero. Starting with slurry cooling and moving forwards, we’ll produce more resources to see what technology can deliver and what it will return for their business.