Methane (Environment and Climate Change Committee Report)

Earl of Leicester Excerpts

Tuesday 13th May 2025 Grand Committee

[The Earl of Leicester (Con)]

My Lords, I had the honour of joining the Environment and Climate Change Committee just as it embarked upon this inquiry into CH₄, which, as we heard from many of our American witnesses, is something called methane.

Let me share a useful analogy with noble Lords. In January 2020, I attended the Oxford Real Farming Conference, where one of the seminars discussed methane emissions and cattle. Methane was like the school bully who, on your first day at school, punches you in the face: Christ, it hurts, but you soon get over it. Carbon dioxide, on the other hand, was more like a malevolent teacher who takes an instant dislike to you on day one and plagues the rest of your educational career throughout your time at school.

We should be proud that our country has led the world on methane reduction; indeed, between 1990 and 2020, we reduced our methane emissions by 62%. Currently, the UK is responsible for just 1% of global emissions—and falling, albeit slowly. That is about 1.5 megatonnes of methane. China is responsible for nearly 70 megatonnes, and rising fast.

Before I go any further, I should pay tribute to our wonderful clerks, who, as our chair elaborated, had to change. They were always professional, hard-working, diplomatic and ready to listen to committee members’ suggestions as to who might be invited to give evidence as expert witnesses. This is an important factor because, too often, it is tempting for clerks to invite those who make the most noise: lobbyists and activists; or, perhaps, their own kith and kin, in the shape of civil servants in government departments whose work is centred around the inquiry’s subject matter. Of course, for obvious reasons, it is essential to invite academics who study the said subject.

Make no mistake, I am very happy to listen to all of the above; indeed, their evidence was essential. However, sadly—for it is often they who can provide the solutions—all too often it is the people who do not get invited who are those folk at the sharp end: the practitioners. They are the people who actually undertake the work, and whose experience of what works and what does not is the most valuable.

I was very grateful to the clerks and the chair, who supported my suggested witnesses, often from the private sector, agriculture and the Agriculture and Horticulture Development Board, particularly Professor John Gilliland, who is an innovative farmer in Northern Ireland. I state my interests, as set out in the register, as a regenerative farmer and landowner in north Norfolk, with a large herd of suckler beef cattle and the ownership and management of the largest, and arguably most important, national nature reserve in the country, Holkham NNR. I shall return to that at the end.

As agriculture is the largest source of domestic methane emissions in the UK, at 49%—and is the sector I understand most—I shall limit my comments to this area. Some 85% of these emissions come from the enteric fermentation process within a cow’s stomach. For the sake of clarity, the vast majority of methane is emitted from the front, not the back, end of a cow, and then a further 15% is emitted from slurry manure. As our chair has mentioned, it is also important to note that we are harnessing methane very successfully in agriculture through the increasing number of anaerobic digesters in the UK, which mimic a cow’s stomach on a much larger scale, capturing the methane and pumping it into the national grid. Crucially, given what happened in Spain recently, this provides a baseload form of energy supply.

It is important to note that globally between 1990 and 2020 it is believed that agricultural methane emissions increased by approximately 12%. Most of this came from less developed countries where populations have increased rapidly and where a gradually improving economic situation has increased the demand for meat in people’s diet. The inquiry looked at various solutions for reducing emissions. The noble Lord, Lord Trees, mentioned diet, feed additives, such as Bovaer, and cattle health, which are very important. Two weeks ago, on a field trip to the Netherlands for our nitrogen inquiry, we saw some really good manure and slurry management which reduces methane emissions.

I have difficulty with the recommendation to reduce the number of large ruminants—by that, obviously, I mean cows. It is true that in the West and the emerging East we all eat too much meat, but we get into very dangerous territory when we start telling people how much meat they can eat. We should, of course, try to educate people on these matters. We must also question the figures emanating from the UN on the standard UN cow used in all methane calculations. A feedlot Hereford bullock eating a diet of maize is very different from an extensively grazed Galloway heifer eating grass all its life, which itself is very different from a Brahman cow in India. There are huge differences in diet, size, length of life and doubtless many other factors. The noble Lord, Lord Trees, made very important points regarding the differences between GWP100 and GWP*.

It is also true that Henry Dimbleby, in his national food strategy, showed that the total biomass of farmed animals has increased by a huge factor since 10,000 BC, when only 2.5 million humans were a tiny proportion of the total biomass of wild animals. That was at the start of the Holocene epoch, when global temperatures entered an unprecedented period of stability and agriculture became possible. Today, the combined weight of all livestock bred for human consumption dwarfs that of the combined weight of all wild mammals and birds, and even adding the combined weight of the now 7.8 billion human population and our domesticated animals, such as pets and horses, it is still much smaller than that of the livestock that we are producing for human consumption.

We clearly have a number of problems: a burgeoning population, leading to a problem of how to feed the world, which we are pretty good at—although we are doing it in perhaps too intensive a way that is not helping biodiversity, et cetera; some of the food is grown in the wrong place; and we have plenty of inequality. Some 50% of the world’s habitable land is put down to agriculture, but of that, 77% is down to either livestock or, pertinently, the production of crops to feed said livestock. In the UK, that figure rises to an astonishing 85%, according to Dimbleby’s food strategy report, although that is partly down to our hilly topography, high rainfall in the west and our temperate climate, which promotes exceptional grass growth. Let us not forget that well-managed, diverse grasslands are very effective carbon sinks, pulling carbon dioxide out of the atmosphere and sequestering free nitrogen in the ground. Grassland is an important tool in the fight against climate change, and we should be careful when we recommend excessive tree-planting schemes— I apologise for the slight diversion.

With regard to methane emissions from cattle, we heard from some eminent academics who favoured beef cattle reared in huge feedlots in the USA and Australia, suggesting that because they were being reared on protein-rich diets and thereby putting weight on quicker, and thence being taken to slaughter quicker, over their shortened lifespan they emitted less methane. That is true, but only in isolation. Where did all that food come from? I have just mentioned the percentages of land use—vast acres growing cereals and maize in the USA, and vast quantities of soya being imported from South America. All those feedstuffs are grown with huge tonnages of nitrogen artificially produced using the Haber-Bosch process, which is heavy on energy consumption, with resultant carbon dioxide emissions leading to excess nitrogen pollution, the subject of our current inquiry. Some 50% of nitrogen applied to fields is lost through leaching into watercourses and into the atmosphere. Further, all are cultivated with large machinery emitting another pollutant, nitrous oxide.

In Britain, where we rear beef cattle for human consumption, the vast majority of animals are extensively reared outdoors for six to eight months when the grass is growing, which is all they eat during that time. Hardier breeds such as Belted Galloway, Blue Grey and Highland cattle spend all year outside. They are an essential component in the carbon cycle and the facilitation of healthy biodiversity.

I return to the nature reserve and the cattle. At home, we have to manage the NNR within strict parameters given to us by Natural England. Yes, the cattle are emitting methane while they chew the cud, but they are also chomping the grass to the correct sward lengths—through careful management as to how long they stay on a particular freshwater marsh, how much grass they eat and how low they eat it to—by which these differing heights and conditions of grassland allow a rich assemblage of differing visiting breeding birds, such as waders, waterfowl and raptors, including marsh harriers, to breed. Of course, their muck returns natural nitrogen to the ground, among other organic matter, and provides essential habitat for dung beetles and all manner of insects at the bottom of the food chain to breed, thereby starting the whole cycle over again and supporting all life.

As we are learning in our current inquiry into nitrogen, reducing emissions is a complicated job. If one concentrates too hard on one reduction, then the law of unintended consequences often leads to an increase in another area.