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Letters to the editor: volume 16, issue 4

Image credit: Patrick Tomasso/Unsplash

Readers discuss the implications of abandoning gas central heating, whether renewables can meet peak electricity demand, the deadly legacy of asbestos in buildings and more.

Central heating switch won’t be simple

There are several things that concern me about a move away from gas central heating to electricity. First, how do we expect poorer people to afford it? Many already have problems at the moment. My own analysis of the full cost of gas and electricity over the last 15 years shows that electricity has varied between three times and six times the cost of gas. Over the past five years this has been between three and a half times and six times.

This is with a cast-iron boiler, which is less efficient than the more modern gas boilers. From my reading on the internet, both air-source and ground-source heat pumps are about 300 per cent efficient, which means up to twice the overall operational cost unless houses are much better insulated. Of course, air-source heat pumps get less efficient as the temperature drops.

How is this going to be achieved with existing houses? This will involve replacing boilers and radiators while possibly installing underfloor heating. Expensive and creating a lot of waste.

I fully support thinking about using potential alternatives such as hydrogen, which should mean maintaining the existing infrastructure. What is the environmental impact of millions of homes in Great Britain removing energy from the air and ground at a time when it can be quite cold already? What impact might this have on wildlife and plants?

Peter Tuson CEng MIET

By email

The cost of going green

The last few days have been almost totally still – no wind. Looking on the National Grid site as I write, wind accounts for just 1.8 per cent of UK power generation, solar is zero (it’s dark) and 1.7 per cent is coming from hydro, so the total percentage from renewables is 3.5 per cent. 62.8 per cent is being generated by fossil fuels, mostly gas, 11.3 per cent is being imported from the continent and 22.8 per cent is ‘other’. The figures have been much the same for the last three days.

The government plans to electrify our homes and cars, which will at least double the load on the grid, and intends to build more wind farms to supply clean energy. However, with the weather as it is at the moment it doesn’t matter how many wind turbines there are; if there’s no wind, there’s no power generated.

If I want to boil the kettle using electricity, 62.8 per cent of the energy comes from a power station using gas to make steam by boiling water to generate the electricity, losing about 10 per cent in the process. The electricity is transmitted to my house, losing another 10 per cent or so in the process, and used to boil the water. The alternative is to boil the kettle using gas without suffering any of the losses, and the cost of the gas is roughly one-fifth that of the electricity.

A similar issue arises with the argument that the cost of running an electric car is cheap because electricity is cheap. Petrol is only expensive because it highly taxed; petrol itself is cheap, whereas electricity is actually very expensive and not so heavily taxed (yet). Charging an EV battery tonight would be effectively filling it using 62.8 per cent of fossil fuels and losing roughly 20 per cent in the process through generation and transmission losses. It would be like filling with petrol and pouring 20 per cent of it onto the forecourt.

Is it me, or is there flaw in the policy of electrifying everything?

John Cowburn FIET

By email

What happens when there’s no wind?

I am not sure that I share Steve Macken’s enthusiasm for wind generation (Letters, March 2021). Sitting with the sun streaming through my window, clear blue skies and the barometer nearly off the top of the scale I look at what is happening on the National Grid (gridwatch.templar.co.uk) and find, as expected, wind is contributing almost nothing – less than coal in fact. Moreover, it has been like that for the past four days. The answer I hear is to install storage capacity, but how many days of storage capacity do you allow for? Then it needs recharging, which requires extra generating capacity and takes time. How many days of recharging will you need before you can cope with the present weather situation again?

Roger N Holden CEng MIET

Stockport

E&T Letters section cartoon Volume 16 Issue 4

Image credit: E&T

IEE centenary memories

I have followed with interest reports in E&T about celebrations to mark the IET’s 150th anniversary. I was privileged to take part in the IEE’s Centenary celebrations in 1971, before it became part of the IET. At that time I was honorary secretary of Sheffield sub-centre of the IEE, and was invited, together with the sub-centre chairman Jim Barratt and our wives, to take part in the celebrations in London.

The main events were a service of thanksgiving in Westminster Abbey followed by an opening ceremony in the Royal Festival Hall; a centenary banquet in the Guildhall hosted by IEE President Lord Nelson of Stafford and attended by the Prime Minister, the Right Honourable Edward Heath MBE; and a conversazione in the Royal Festival Hall, attended by HM The Queen and the Duke of Edinburgh.

In Sheffield, we staged an exhibition showing the history and development of the telephone. We had on the sub-centre committee the head of British Telecom in Sheffield, Rex Thompson, and he was able to obtain a number of historical items from London. The exhibition was held over several days in Telephone House in Sheffield, and was well attended. It had a particular relevance in Sheffield, since it was here that in 1879 John Tasker installed one of the first provincial telephone exchanges in the country. Tasker also installed private telephone exchanges for Queen Victoria at Windsor Castle and Balmoral, and the Sheffield exchange was visited by the British Association for the Advancement of Science.

We also arranged a competition for local schools. I can’t remember what they had to do, but the standard reached was very high and we presented each school with a commemorative shield bearing the IEE Coat of Arms in the shape of a car radiator badge that the Institution used to sell. Such badges were popular at the time, but I imagine very few are now extant.

I joined the IEE as a student in the early 1950s, and when the IEE became part of IET I received a lapel badge commemorating 50 years of membership that I still wear with pride. I no longer play an active part in IET activities, but always read almost all the articles in E&T. I wish the Institution every success in the celebrations, and in the future.

Roy Smalley CEng MIET

By email

Load management won’t be popular

If there is really going to be a significant increase in the use of electric cars soon, it’s likely that many residents will want to install charging units at home. Recently, the distribution network operator (DNO) for the area where I live has replaced all its buried cable and renewed the local transformer. This was done on account of cable failures that have caused a batch of local power failures due to insulation faults. It appears that this was, more or less, done on a like-for-like basis (albeit using a lot of plastic cable ducting under some drive entrances, not directly burying all the new cable). The cable is downrated by about 15 per cent, according to the supplier, in a duct compared with direct burial, no doubt to keep its temperature under control.

If all the residents eventually increase their load due to EV charging, it could be that even more underground works will be required. Historically, load diversity would not be used in the sums for this. The alternative may be to increase ‘load management’ to avoid the need to upgrade the network. Whether the customers (who are mostly customers of various utility suppliers, not the DNO) would like it is another matter. I note that in BS7671, there is an entry to this effect: “722.311.201 Load curtailment, including load reduction or disconnection, either automatically or manually, may be taken into account when determining maximum demand of the installation or part thereof.”

It may be that the current structure of the industry is inimical to the concept of using load management across the system, with a range of different contracts between customers and utility suppliers. However, I’m aware that at least one of the utility firms operating locally does offer a system that can be remote controlled for variable pricing etc. It’s not clear how that will work in a competitive market.

John Keepin MIET

By email

Interdisciplinarity myopia

I recently contacted an E&T reader for advice on problems facing an artist trying to communicate with scientists. As part of his response he drew my attention to the letter from Peter Tuson in the December 2020-January 2021 issue. Having spent much of the past 20 years supervising arts-based doctoral projects, I’m entirely in agreement with what he says. However, we need to be realistic about the problems involved.

Recently I was contacted on just this issue. Having presented arts-led work at a conference, an artist was invited to submit a paper on her doctoral work to a science journal. Despite numerous attempts to respond to referees’ comments, she was finally told the journal could not publish her work as it was insufficiently scientific. She responded by explaining to the editor that her inability to act like a scientist was due to working as an artist.

The editor responded in turn by expressing sincere disappointment at not being able to include her work, conceding that scientists like to think they work with artists but instead convert their work into something more acceptably scientific. She was also applauded for holding her ground. Finally, she was thanked for causing the editor to stop and think about the ways in which journals and their editors undermine artists’ contributions to vital debates. Significantly, however, this response was sent from the editor’s private email address.  

This account confirms my view (as a former journal editor) that the constituencies journals represent are often profoundly resistant to broadening their understanding beyond disciplinary concerns, often despite paying lip service to notions of ‘interdisciplinarity’. A myopia that, in this age of socio-environmental problems, we now urgently need to address.

Dr Iain Biggs

Honorary research fellow, University of Dundee; Visiting research fellow, Environmental Humanities Research Centre, Bath Spa University

Hidden threat of asbestos

I read with interest the article in the April 2021 issue of E&T on the increasing prevalence of asbestos-related illness and deaths in the UK. I have recently moved into a house that was originally built in the 1930s, and our building surveyor identified a number of possible asbestos risks. We have decided to have the asbestos properly removed, but what has really concerned me is the number of people, including tradespeople, who have suggested boarding it over, effectively hiding it.

We are aware it is there because our surveyor spotted the tell-tale signs, in our case an Artex ceiling as well as some smooth ceilings with wooden battens on them, these latter ceilings being constructed from asbestos cement boards held in place by the battens. If these were hidden by skimming the Artex or boarding over the battens the asbestos would still be there, but the visual indicator would be gone, placing a huge obligation on the integrity of us and future owners of the house to inform future purchasers.

It would only take one forgetful, or unscrupulous, owner in the future for this chain to break down and a subsequent owner to be unaware of the presence of asbestos, placing themselves, their families and any tradespeople working in the house at significant risk.

Even without carrying out any work, consider the situation where a burst water pipe causes a ceiling to collapse into the room below, spreading asbestos-containing material which the owner does not know is present. From what I’ve experienced it seems that hiding asbestos in this manner is very common and I fear could lead to significant cases of unwitting exposure in years to come. I am surprised it is allowed.

David Cowdry MIET CEng

By email

Smart meter benefits are here

For those who doubt whether we will ever get value from the millions of smart meters across the electricity network I can confirm some good news. They send half-hour voltage readings from customers’ incoming terminals, and studies have revealed an alarming fact – many customers are receiving voltage which is outside the upper statutory limit.

Distribution network operators have traditionally maintained the despatch voltages at the upper end of the statutory range in a belief that voltage drops across the network. With far-end generation the drop is less and at times the ‘send’ voltage exceeds the upper statutory limit of 253V.

In 1993 the nominal UK voltage of 240V was harmonised with the EU at 230V but network operators did not alter their policies and continued to push out volts in the range of 230-250V.

An innovative project with Northern Powergrid and the community of Boston Spa in Yorkshire has found that volts can be dropped by about 5 per cent. This brings the benefits of a 5 per cent reduction in energy bills, reduced carbon dioxide emissions at power stations, and a release of capacity on the distribution network. And the clever part of the ongoing project is that the system will operate in an active closed-loop control system where ‘live’ customers’ smart-meter voltage readings will be used to vary the primary 11kV system such that voltage will be optimised downwards to bring all the benefits but with protection so that the far-end customer voltage does not fall below the lower statutory limit.

Yes, reduction in voltage does reduce energy consumption (contrary to simplistic counter arguments that amperage will rise and energy remain constant). The expectations are that when this new control system is rolled out all of the four million customers in Yorkshire and the North East will get savings of 5 per cent (about £40) every year.

What a pity our distribution engineers did not join up the dots and realise that voltage has been too high for over 20 years. Thanks to smart meters we have realised the inherent problem and here in Yorkshire our DNO, Northern Powergrid, has warmly welcomed the challenge to correct matters. Other DNOs should follow suit for the benefit of customers, the climate, and their networks.

Keith Jackson CEng FIET

Boston Spa

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