Anaerobic Digestion in Chatteris – Renewable Energy for Cambridgeshire

maize08:08 Thursday 24th April 2014
BBC Radio Cambridgeshire

[P]AUL STAINTON: Proposals to build an anaerobic digestion plant in Chatteris are being put out to consultation. If it gets the go-ahead it will see a huge plant built near the Mepal Outdoor Centre which will process maize and then turn it into energy. It could be a lifeline for some farmers, who could grow maize on their farms and then turn it into energy and act as a second income. .. Joining me on the line now is Matt Hindle who is a policy manager at the Anaerobic Digestion and Biogas Association. Matt, good morning.
MATT HINDLE: Hi there Paul.
PAUL STAINTON: Just tell us a little bit about your association. What does it do?
MATT HINDLE: We’re the trade association for anaerobic digestion. In the UK we represent about 350 businesses who are involved in all parts of developing anaerobic digestion plants, and that can be on farms , that can be to treat food waste from homes and businesses, on food production sites and for water companies on sewage treatment sites.
PAUL STAINTON: In a nutshell, if you can, could you simplify what anaerobic digestion actually is?
MATT HINDLE: It’s not the most nattily titled technology.
PAUL STAINTON: No it’s not. I’ve been struggling with it all morning. energy from waste is easier
MATT HINDLE: Well that can encapsulate a number of things, and anaerobic digestion is one particular process. It’s a natural process. It uses bacteria to break down organic matter from the sort of material I’ve just mentioned, so food waste, farm material and sewage waste. But anything with organic content basically. That’s broken down in the absence of oxygen, hence anaerobic. And that produces biogas, which is captured to produce renewable energy, and is a very flexible form of renewable energy.
PAUL STAINTON: So there’s no burning going on, or anything like that. It’s just a natural way of doing it.

Is this different to the other systems like the Terminator in Waterbeach? Is that different?
MATT HINDLE: I’m afraid I’m not familiar with Waterbeach.
MATT HINDLE: But it’s certainly different to pyrolysis or incineration or as you say forms which directly use combustion to release energy. This produces a gas which can be made very similar to natural gas, to go into the pipeline. And it’s one of the only forms of renewable gas that can do that, so that’s a particularly exciting area.
PAUL STAINTON: Is it particularly green? Is it safe?
MATT HINDLE: It’s particularly green for a number of reasons. Firstly because it’s using naturally occurring bacteria it’s very low carbon. And also the anaerobic digestion process recycles the nutrients in that organic matter, so they can go back to farmland as a form of renewable fertiliser.
PAUL STAINTON: This sounds like a win-win situation. It sounds absolutely brilliant. Why are there not more people doing this all over the country? Is there a downside anywhere, apart from the fact that you’re going to turn over acres and acres and acres of your farmland to grow maize?
MATT HINDLE: Well I imagined we might come to that, but first of all part of the reason that it’s not more common than it is is the capital cost for putting the tanks in to do this has historically been quite high. And that has been falling, and we’ve seen quite an increase in the number of plants across the country, even in the last few years. We’ve grown from about 50 plants in 2010 to around about 140 now. So it is very much a growing sector, lots of UK companies, UK manufacturing.
PAUL STAINTON: Is the only downside then that you’ve got to give over a certain amount of acreage to rather than food production, to energy production?
MATT HINDLE: Well I think we should recognise that land in general has always been used for food production and fuel production, used for fibre, for clothes, used for leisure and recreation. So land use is a very mixed picture. But biogas is a particularly good form of bioenergy, and we need bioenergy from land in some form to keep lights on, to reduce our carbon emissions. The Committee on Climate Change are very clear on that.
PAUL STAINTON: Sure. Does it smell?
MATT HINDLE: There generally isn’t an odour problem with plants on farms. So there are about 140 plants. There have been a very few incidents at some plants, but that’s typical of both farming operations and anything treating any form of organic waste. There are ways that plants can minimise that, and it’s obviously something that the Environment Agency regulates.
PAUL STAINTON: Bob Lawrence is with us as well, the County Chairman of the National Farmers Union. Bob, morning.
BOB LAWRENCE: Good morning.
PAUL STAINTON: We should all be rushing, shouldn’t we, to build these all across the country, shouldn’t we? It sounds fantastic.
BOB LAWRENCE: I don’t think we should all be rushing.
PAUL STAINTON: Why is anybody against it Bob?
BOB LAWRENCE: I think it’s a protection problem really, that we’ll be suddently growing maize everywhere, and I don’t think that’s actually the case. And I think that AD, and maize production for AD can sit nicely in a farm and complement the production of food quite nicely. And it’s not about food or fuel. They both sit alongside each other pretty well.
PAUL STAINTON: Yes. It’s quite a lot of hectares need to be given over though to growing maize for this plant, isn’t it? In one respect I suppose that’s a nice little earner, isn’t it?
BOB LAWRENCE: You can earn money from it alongside food production as well. If you think that currently in Cambridgeshire we’ve actually got two AD plants going, one at Littleport and one at Chittering, and they roughly from our last calculation took up about 3,500 hectares of maize, which is less than 1% of our productive agricultural land in Cambridgeshire. So we’re not going to all of a sudden see acres and acres of maize growing everywhere. Perhaps near the AD plants I’m talking about there will be a concentration of maize, but we’re not suddenly going to be short of food just because we’re growing maize for AD production.
PAUL STAINTON: Is it something though that increasingly farmers are having to look towards to other income streams, whether it’s growing maize for anaerobic digestion or putting solar panels or wind turbines on their land? Is it something increasingly farmers are having to do?
BOB LAWRENCE:¬†Farmers are looking at all the things you mentioned plus other things as a means to diversify and have productive profitable farms and businesses. And I think that’s very important and they can be complementary to food production. As your previous guy spoke, particularly in the Cambridgeshire area, AD fits well with what we’re doing, because with all our vegetable processing plants there’s a lot of waste produced, whether it’s carrots, leeks, onions. And they can all be fed into these plants as well. So the maize is used as a high energy feed bank as part of the feeding of the AD plant. So it actually fits really well. And then of course there’s the by-product, which has a nutrient value at the end, which can be spread back onto farmlands. So it should be a good environmental story for us.
PAUL STAINTON: Is there any downside for farmers out there? Can you see any downside to it?
BOB LAWRENCE: The downsides are in really tricky wet autumns, when potentially you’ve got issues with vehicles on the road, which you would do with any crop anyway. But as long as those issues are carefully managed, it should sit well in a farming system.