Letters to the editor: volume 18, issue 4

Why are we ignoring potential of SMRs?

We continue to see letters like the one signed by ten MPS that was published in the Daily Telegraph recently, claiming that renewable energy is cheap. But solar and wind farm owners do not pay for the energy-storage facilities needed to maintain supplies when there is little sun or wind. It is consumers and taxpayers who pay for the very expensive energy storage – to which must be added the hundreds of millions in taxpayer subsidies that help to fund solar and wind farms.

National Grid estimates that it will cost £3tn to decarbonise the grid and carry the load of millions of electric vehicle chargers and heat pumps, with an average capacity probably of 100,000MW. Wind farms and energy storage are far from cheap.

You can buy 100,000MW of small modular reactors for around £0.5tn, which – unlike wind turbines – can be located closer to centres of load, with less need for new transmission lines. Also, SMRs would require nothing like as much energy storage as wind farms and would avoid the need for periodic replacement of grid-scale batteries. Why is that option being ignored?

Roger J Arthur CEng MIET

By email

Emphasise climate change’s impact on us all

The April 2023 issue of E&T is hot on greenwashing, but does not hammer down enough the implications of inaction. The editor’s letter successfully explains greenwashing, and articles describe how climate change is leading to change in individual parts of the planet, but overall it makes the usual mistake of not stressing the inevitable impact on us – by which I mean on all life.

The Graphic ‘Doomsday Glacier’ melting fast shows the size of Antarctica alongside central and western Europe, and says that the melting of the Thwaites glacier could raise global sea levels by half a metre. Many parts of northern Europe are barely above sea level now! I have driven across the southern end of The Wash and can profess to its utter flatness. I know also that a significant part of the Fens to the south are below sea level now. The same applies to much of The Netherlands – hence its name. Why not have one map of Europe showing the bits of it that are below sea level now, and another showing the bits of it that will be below sea level once the sea level has risen by half a metre?

‘Let’s Talk Climate Action’ focuses on motivation, but completely misses the opportunity to cover what will ultimately motivate the human population, which will be how disastrous climate events will become as things get warmer and warmer. All of this carbon dioxide needs to go back into the ground where the coal, oil and gas from which it was made came from, or surely many important ways of life all over the world will cease to be viable.

My life will end before much of this happens, but think of this: studying geology in the mid-1970s in Shropshire, I was intrigued as to why 50 million years ago a region north of what is now the Thames estuary was an island. That island is where I sit as I write this and is now largely occupied by the conurbation of Southend-on-Sea, Hadleigh and Rayleigh. The reason it was an island back then was because carbon dioxide levels were much higher than immediately prior to the beginning of the Industrial Revolution, and so the climate was much warmer. Therefore, the sea level was much higher.

This is not doomsaying, this is pointing to what has happened before and is surely likely to happen again.

Until the implications of inaction are faced up to, the immense ingenuity that homo sapiens has already shown itself capable of will not be adequately brought to bear on this existential crisis that my children will be privileged to observe in more severity than I will.

Peter Swadling

By email

Plenty of potential for tidal energy

I completely agree with Stuart MacArthur (Letters, April 2023) that much more consideration should be given by the UK to using the power of tides; after all, we live on an island and the ebb and flow of the sea is totally predictable.

In fact, it would be possible to build structures in appropriate places that could incorporate other useful facilities, such as a desalination plant producing fresh water and sea salt. An electrolysis system could also be included to produce hydrogen for use as replacement for the fuel currently used in IC engines, together with a wind turbine and photovoltaic cells, thus making the most of all of the freely available green energy sources.

Peter Taylor CEng MIET

By email

Steel from the sea

Could the UK produce cheap green steel using tidal energy? The Hybrit process, in an advanced state of development in Sweden, uses green hydrogen instead of coal. Enough hydrogen has to be stored to keep the process going during lulls in the supply of renewable energy and the cost of storage will be a significant contribution to the cost of the process.

Using tidal energy to generate hydrogen would be particularly elegant as only enough hydrogen has to be stored to keep going for the predictable few hours when the tide turns. This hydrogen could be stored at low cost in undersea ‘bells’. The hydrogen would be generated close to the turbines, simplifying the need for electrical transmission.

The UK is noted for opportunities in tidal power, so ‘green’ steel should give us a distinct market advantage for export to countries serious about reducing their carbon footprint.

John Greenwood FIET (retired)

By email

On-the-go charging for EVs?

Following the recent announcement of a high-temperature superconductor, how long will it be, I wonder, before they are laid in main highways to run and charge electric vehicles so that they rarely need charging while stationary? It is possibly the only solution to providing sufficient static chargers when EVs are all we have, but personally I feel that hydrogen may be a better answer.

Derek Himsley MIET

By email

Applying food bank principles to energy

Your recent online news story ‘Calls to launch a social energy tariff for poorest households ramps up’ prompts me to suggest a scheme that could greatly help needy families, relieve peak-time generation at the electricity grid and give a needed boost to UK battery manufacturing.

The news is full of stories of needy families locked into extremely high electricity prices. With government support, a national scheme inspired by food banks could be a great help. A power bank would do the same – provide help with what is actually needed.

To mimic the gathering up of surplus food from supermarkets, a power bank would gather up surplus power generated at night at low marginal cost. The government would simply purchase, install and fill (at night) grid-scale batteries distributed at convenient locations around the country to load up a quantity of electricity to match the scheme’s daytime commitment to eligible needy consumers. This would be fed back into the grid during the day to match demand. Such a scheme could supply power at an exceedingly cheap social tariff (but ideally completely free), and at the same time provide some much-needed relief for the grid at peak times when demand is currently met by fossil fuel generation.

Back-of-the-envelope calculation: assume half a million needy households would be eligible, that their allowance (also to cover some heating) would be 25kWh/day and that the individual (grid) battery system size would be 600MWh. The power bank would consist of 21 battery systems dotted around the country at convenient locations for grid connection. Such a scheme could remove 12.5GWh from the daytime grid (at present powered by at least two expensive fossil-fuel gas power stations at peak times) and replace it with green electricity at almost zero marginal cost.

If we assume the (reducing) cost of grid-scale battery storage is now down to, say, £250/kWh, then each battery system would cost about £150m, making the total power bank cost just over £3bn for 21 of them.

Providing the battery systems would of course require this significant capital expenditure up front, which only national government is in a position to fund. However, the investment can surely be regarded as a very sound one, because government would then expect to receive a guaranteed payback in terms of savings in the benefits budget for all time thereafter. The scheme’s viability would only increase over the years as the proportion of green electricity (at night) is ramped up as planned.

If the above (non-expert) calculations are anything like correct, the cost of such a scheme looks relatively modest in the context of government’s huge spending on benefits generally (eg £100bn on working-age benefits alone).

Perhaps this all represents a techno flight of fancy by an IET member whose qualifications are long past their sell-by date: but there will be many others with up-to-date qualifications and experience able to judge the viability of such a scheme. Is it nonsense, or does it represent the kind of big picture within which all the necessary technical, financial and administrative detail could then be painted?

Nigel Morgan MIET (retired)

By email

Which net zero?

After reading ‘Carbon Concealed’ in the April 2023 issue of E&T, I am more confused than before on the exact meaning of net zero. Is it the IPCC definition, net zero from ‘cradle to grave’, territorial net-zero, unitary authority area net-zero (which I have seen used by my local council), Scope 1, 2 or 3 as defined in the article, or none of the above but just what I wish it to be defined as?

It should be noted that the article makes no reference to the IPCC definition. Please can E&T have one definition or, failing this, can articles make clear which definition is being used?

Shaun C Kerigan CEng FIET

By email

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