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We are informed that the wholesale price of natural gas has tripled since April…

We are informed that the wholesale price of natural gas has tripled since April and that this is forcing many fuel supply companies into closure, threatening the production of carbon dioxide and ammonia. Farmers are unable to send their pigs and hens for slaughter or get the fertiliser they need, and the government is in its usual spin trying to get a grip on fuel prices while maintaining the productive economy. I’ve been banging on about CO2 being the cause of all our problems and now it appears there is not enough of it. What on earth is going on?

Use of carbon dioxide

In my second article in this series ( 18 August ), I wrote about CO2 as the gas mainly responsible for climate change. It is produced mostly by combustion of fossil fuels, including natural gas, but it does also have some uses, indeed over 13 million tonnes (Mt) of it are used across the world each year, 20% (2.6Mt) of this in Europe.

It is used in the food industry to make flavourings, to keep food fresh in packaging, to carbonate drinks and to extract caffeine from coffee. It is used in medicine to make some drugs like aspirin and in laser and keyhole surgery. In frozen form, it is used in refrigeration and for cleaning machines, and in the chemical industry it is used as a feedstock and for extraction of contaminants. In agriculture, it is used for silage fumigation and to increase greenhouse productivity. It is the usual means of rendering animals less conscious prior to slaughter. And it is used in firefighting and welding.

Ideally, we should use the CO2 produced in combustion processes in a virtuous circle for these purposes and, to some extent, we do. For example, some big breweries capture the CO2 produced by fermentation and use it to carbonate drinks and for other purposes in the production. But most industries, notably cement, ammonia and lime manufacture, power generation plants, and aluminium and glass manufacture, capture little if any. It is a waste gas cast into the air, thus contributing to climate change. Extraordinarily, all those industries that use CO2 in the UK appear to rely on two small fertiliser factories capturing the gas and selling it. Those factories have now found that the increased price of gas will require them to cease production.

Ammonia

Ammonia is key to the production of fertilisers and is a topical example of the inter-connectedness of climate change and industrial activity. Ammonia (NH3) comprises nitrogen and hydrogen, and is made by combining these two gases at high temperature and pressure, using an iron-based catalyst. The nitrogen is derived from the air, but the hydrogen is made from the methane in natural gas, a process that requires a lot of energy and produces CO2 as a by-product. The energy is provided by electricity, so the process can be doubly dangerous in terms of climate – fossil fuel, usually natural gas, provides the energy and CO2 is given off.

Indeed, worldwide ammonia production is estimated to produce some 450Mt of CO2. However, the CO2 can be captured, and this is the main source of the gas for the commercial market. If the process uses renewable electricity, it can be said to produce green ammonia.

Some readers will remember making ammonia in school chemistry classes; once smelt never forgotten, as it is a very pungent gas which can be painfully fatal in industrial accidents. Nevertheless, it is useful for making fertilisers (giving its nitrogen to plants), for making explosives and many other chemicals, and as an energy store and potential fuel. However, it requires eight million Watt hours (MWh) of energy to make one tonne of ammonia which holds only 5MWh of energy, so benefits in terms of climate from its use as a fuel must be from the use of green energy in its manufacture.

Gas supplies

It would be nice to think that our use of natural gas is provided for by our own production from wells in the surrounding seas, as our coal gas was once provided by our mines. However, we only produce about 48% of the gas we seem to require. In 2020, we produced 438 billion Watt hours (TWh) worth of gas and imported 478TWh. Two thirds of this came from Norway but significant amounts in liquified form came from Qatar, USA and Russia. We used 299TWh in our homes, 231TWh in electricity generation, 94TWh in other industries and exported 94TWh.

In 2020, emissions of CO2 in the UK totalled 300Mt, of which 56% (168Mt) came from natural gas. It is thus now our major producer of CO2 and therefore driver of climate change, and must be a target, along with oil, for rapid reductions in use. Those 168Mt from gas that go to waste dwarf the 3Mt required annually by the food and other industries.

The current dramatic rise in wholesale gas price seems to be related to a rise in worldwide demand related to economic recovery from COVID-19, together with restricted supplies from Russia, presumably for political reasons, and problems with pipelines. It would appear that this is compounded in the UK by lack of adequate storage facilities for gas, a consequence of government short-termism and over dependence on the private sector and fragile supply chains. The knock-on effects are a revelation, at least to me.

The lessons

This episode is an object lesson in the reasons for having an overall energy policy in the UK. Changes in the price of a commodity we produce ourselves and the use of which is driving climate change has caused what will be huge and disproportionate costs to the least well-off to keep themselves warm. It has also had effects on fertiliser, food production and packaging, with the potential to cause food price increases and disastrous effects on food processing, delivery and prices, by a chain of events that would be a joke were it not so serious.

These disastrous effects, not yet realised as I write, seem to be a consequence of lack of natural gas storage facilities for more that a few days and concentration of the UK’s production of fertiliser and commercial CO2 on two small factories. Such a bottleneck would in wartime have been a tempting target for enemy bombers. No doubt the Kremlin is aware of this.

I hope that by the time you read this, the short-term problem will have been solved. An obvious answer is rapid government support for the energy costs of the fertiliser factories and arrangement of a more diverse supply chain for CO2. The alcohol industry is an obvious source since they are major producers and almost all their CO2 goes into the atmosphere.

In the longer-term, we need to balance our production of natural gas to our declining use of it and to direct this decline particularly to imported gas. And to stop using gas, each of us will need to reduce our personal need for it and urge the government to accelerate the development of wind, solar, wave, tidal and nuclear energy. This is what an energy policy is about.

Anthony Seaton is Emeritus Professor of Environmental and Occupational Medicine at Aberdeen University and Senior Consultant to the Edinburgh Institute of Occupational Medicine. The views expressed are his own

By Anthony Seaton | 22 September 2021

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