More Maize Madness: Far from being a climate change panacea, producing Biogas helps intensify its consequences

Tackling climate change is one of the most pressing and urgent things facing humanity, alongside (and related to) the 6th Global Extinction crisis. Some suggest that tackling Climate Change trumps all other considerations.

One of the biggest consequences of climate change facing the UK is severe flooding due to increasingly intense rainfall.

But flooding is exacerbated by unsustainable types of land-use. Maize is one of the most unsustainable and environmentally damaging crops it is possible to grow in the UK.

maize field flooded

Somerset Levels Maize field, flooded.

One of the reasons for this is that Maize is harvested so late in the season that the ground is too wet to do anything with, after the harvest. So fields are left either with stubble over winter, or rough-ploughed. This field is in the Somerset Levels, the scene of intense flooding two years ago.

Maize harvesting involves a forage harvester driving up and down over the field and tractors and trailers driving alongside collecting the maize harvest. So all the traffic across the field compacts the soil which leads to water running straight off the compacted surface – akin to a tarmac-ed car park.

It is therefore somewhat ironic that the NFU are pushing for much more Maize to be grown – to supposedly help alleviate climate change. Maize for biogas, they say, will help mitigate climate change by replacing fossil-fuel derived natural gas with biogas, produced by fermenting maize. the NFU would like to see well over 200,000ha of land converted to grow biogas Maize. I’ve previously criticized the maths underpinning the idea that growing biogas Maize actually saves any carbon at all; and the ridiculous double subsidies that support its production. What I hadn’t appreciated then was how much maize is needed to fuel these Anaerobic Digester (AD) plants.

We have an AD plant on the outskirts of Dorchester at Rainbarrow Farm, next to Prince Charles’ model village of Poundbury. In fact the plant is partly owned by Prince Charles via his Duchy of Cornwall. I imagine Duchy farms in the area (for there are many) also grow the maize to fuel the plant. I was a bit surprised, last Autumn, to see tractor with trailers full of Maize trundling through the streets of Dorchester on their way to the digester.

Anaerobic Digestion can in theory turn all sorts of green waste into environmentally friendly biogas. But in the case of Rainbarrow Farm, two thirds of the plant’s feedstock is maize – that’s 26000 tonnes of maize. If that sounds a lot, that’s because it is a lot. Maize is highly intensive crop, producing around 50 tonnes per hectare of farmland. That means over 500ha (1200 acres) of farmland is needed, just to supply one small AD plant. Still, you might think that’s worth all the environmental damage, increasing the risk of flooding, destroying the wildlife (and fishing) quality of rivers by filling them with polluted sediment. After all, what’s more important than tackling climate change?

The only problem is this: apart from the fact that growing maize to produce biogas has a much bigger carbon footprint than anyone in the industry likes to admit, this AD plant creates enough gas for around 2000 houses per year. With 200,000 households in Dorset, we would need to be growing 50,000ha of maize to supply them with gas.

That’s half the area of arable land in Dorset.

Meanwhile the NFU continues to push for landowners to be paid for the loss of crops when floodwater is stored on farmland, following the successful case last week. This would presumably include loss of Maize crops grown for biogas, on land that had formerly been permanent pasture. Pasture which, until it had been converted into Maize, had been very good at holding and storing flood water, without any damage to the grass crop. As Private Eye would say, Trebles all round.


About Miles King

UK conservation professional, writing about nature, politics, life. All views are my own and not my employers. I don't write on behalf of anybody else.
This entry was posted in Anaerobic Digester, biogas, climate change, flooding, Floodplains, Maize and tagged , , , , . Bookmark the permalink.

25 Responses to More Maize Madness: Far from being a climate change panacea, producing Biogas helps intensify its consequences

  1. hilw3 says:

    Reblogged this on hilarywhitehead and commented:
    Something needs to change!

  2. Tim w says:

    Meanwhile in somerset… check out this picture of a digestate lagoon under construction. No Planning Permission required!

    • Miles King says:

      thanks Tim – and thanks also for pointing me towards your excellent website. There certainly is a lot of Maize being grown around the plant at Cannington – coincidence I’m sure! I’ve written many times on the biogas maize scam – you might be interested to have a mooch through the blogs.

      • Sue Everett says:

        Vercourt just bought Cannington agricultural college farm apparently. Wonder what type of farming that college teaches? Shall we hazard a guess …. Hmmm

  3. Vern says:

    No coincidence. It is well known around here that the company is looking for 3000 acres to grow maize and some fodder beet specifically for the digester. That’s about 48 000 tonnes per year. The company will still take in waste from London, Swansea etc to make up the 65 000 tonnes input our local councils permitted.
    As you point out, subsidies make this a very profitable business. The rents offered for farmland near the digester are now much higher than someone looking to enter farming can afford. Meanwhile landowners can get more money by letting land for maize than using the same land to produce food.
    Why is a field full of solar panels not classed as agriculture but a field full of maize grown for the same purpose is and therefore gets all the planning advantages and subsidies which are meant to help those who produce our food?

    • Miles King says:

      thanks Vern. It’s a very good question as to why solar panels require planning permission but growing maize doesn’t. It dates back to the 1947 Town and Country Planning Act when Agriculture was included in the General Development Order, and exempted from requiring planning permission. According to the law only “development” requires planning permission; converting, say, an old permanent pasture into a maize field, even if specifically to grow maize for biogas, is not considered to be “development” in law, and therefore does not require planning permission.

  4. Reblogged this on Peddling and Scaling God and Darwin and commented:
    An excellent post on the scourge of growing maize.

    In Lancashire you can see the damage after harvest when the soil is bare.

    Not that it is soil but rather some kind of infertile dust which is then washed into streams and nearby roads

    His best comment is seeing Climate Change as trumping every other consideration. Once we see everything though a myopic and distoring lens of Climate Change we , in fact, do far more damage to the environment than Exxon or Shell could ever do

  5. Reblogged, as it is what I see in Lancashire

  6. We need (perhaps you can supply) a full analysis of the environmental impact of maize (in the US, of course, “corn”) biofuels. I read somewhere that if you take into account the carbon dioxide produced by the land being tilled, the carbon footprint of this so-called renewable is greater than that of fossil fuels.

    • Miles King says:

      thanks Paul. I did some of my own calculations on this a while back – see what you think.

      • I think you are far too generous to maize. It is double counting to take credit *both* for CO2 saved when the fossil methane is not burnt, and *also* for all the CO2 absorbed by growing maize, when CO2 equivalent to that first saving will be re-emitted anyway when the biofuel gas is burned. In fact, you would need to consider the fate of the entire maize plant. Is it effectively buried in the soil (good), or do bacteria ferment it and release methane into the atmosphere (far more injurious, for many decades, than the CO2 absorbed in growth)?

        I’m beginning to think that the entire present biofuel industry is based on a failure to think things through. Climate change makes business as usual unacceptable (it does); therefore we must do something, and biofuels are something. So let’s do it, without pausing to ask whether it might actually be makes things worse. Rather like the argument for certain military interventions.

      • Miles King says:

        thanks Paul – that is a very good point! I have missed out the CO2 produced when the methane is burnt. That makes the idea that biofuel maize does anything other than line a few people’s pockets even more ludicrous.

  7. Sue Redshaw says:

    Hi, Miles I have noticed how bad maize is for the land around here (East Sussex) BUT, interestingly, a local farmer told me that they are now required by DEFRA to grow a crop, such as mustard, under the maize to stabilise the soil. Could you comment on this, please. Sue

  8. Sue Redshaw says:

    I believe this is mustard and it seems to be growing OK. I will keep an eye on it and, if I see Richard, I’ll quiz him some more! This was an issue mentioned on Countryfile a few months ago.

  9. Pingback: The continued growth in maize cultivation in Devon – A Dartmoor and Devon blog

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  12. Tina Cox says:

    I live in a very small village through which trundle tractor after tractor on the way to AD just outside Dorchester. We do not have so much as a pavement to walk on and the narrow and bendy road takes an appalling battering from the tractors. The noise is dreadful. Many of the tractors come off the A35 and come through the village (and one other) to get to the digester when they could stay on the A35 and turn off at Monkeys Jump roundabout which would mean the only building they would pass by would be McDonalds. I do not understand why a business is able to cause so much disruption.

  13. Pingback: Climate Action, food and farming: a seismic shift for the NFU? | a new nature blog

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