By Chris Winward
Recently, I have noticed increased appetite among investors to explore renewable energy investment options. This is no doubt related to the numerous calls for a green recovery from the current economic situation resulting from Covid-19, as increasing renewable energy capacity now is imperative to avoid the worst effects of climate change.
With this, many potential investors have been asking me a simple question – how sustainable is anaerobic digestion?
My answer, of course, is ‘very sustainable’ and here’s why.
1. Proven technology
People have been harnessing the benefits from anaerobic digestion for thousands of years. Proven anaerobic digestion technologies have the potential to deliver 30% of the UK’s carbon 2030 carbon budget in the hardest to decarbonise sectors, provide green heat to 6.4 million homes and create 30,000 jobs by 2030. We do not have to wait for the technology to be developed, it is available now.
2. Powered by waste
Anaerobic digestion plants are mostly powered by waste materials, such as domestic food waste or agricultural waste like manure.
Waste is a reliable input. There are always going to be sources of unavoidable waste generated through human activity, which makes waste a sustainable feedstock option for anaerobic digestion. Even in the current economic shutdown, rubbish collections from councils have kept running, with only minimal disruptions.
Also, by using waste for power, anaerobic digestion plants can avoid peaks and troughs in the supply of energy generated. This differs from other forms or renewable energy technology, like wind and solar, which are weather dependent.
3. Reducing waste to landfill
The anaerobic digestion process makes efficient use of waste. Feedstock materials are broken down to produce biogas and a digestate bi-product which farms can use as fertiliser.
Given that the technology is available, I think it is socially unacceptable to send materials to landfill that could otherwise be used to generate power to heat homes and businesses. From 2023, all household food waste in England will be collected separately, which will help ensure it can be directed away from landfill.
4. Confidence in return on investment
For investors, a project must offer assurance of return on investment. In recent months anaerobic digestion plants have shown themselves to be resilient. All our operational plants have continued running despite economic shutdown, so their income has been maintained.
Anaerobic digestion plants currently receive a revenue stream in the form of RHI tariff guarantees for 20 years. This offers assurance and peace of mind, that once built, a new well-run plant should be able to run at a profit. Potential investors can be confident that there will be financial returns on an investment, and the project will be economically sustainable. Registration for RHI has recently been extended to January 2021, and the government is currently consulting on future support for low carbon heat, including green gas support.
Now is the ideal time to refocus investment into the green arena. Existing anaerobic digestion technologies offer a sustainable alternative to fossil fuel gas. There is a perfect opportunity to increase production of biogas through the development of new anaerobic digestion plants to generate energy from waste. These can contribute towards displacing the need for fossil fuels, decarbonising the economy and achieving net zero emissions.
For more information on how energy from waste can contribute towards a green economy visit our manifesto.