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Letters to the editor: volume 18, issue 1

Image credit: Patrick Tomasso/Unsplash

In the February 2023 issue of E&T, readers discuss recycling, regulations for domestic wiring and more.

Can we ever achieve a zero-waste economy?

Reading the article ‘Is Chemical Recycling Greenwashing?’ in the December 2022 issue of E&T, I wondered why landfilling plastic waste does not qualify as a method of carbon capture. If plastics are made ultimately from hydrocarbons and if they last for millions of years in the environment, as is so often the complaint of green campaigners, then why not make a virtue of it?

I dutifully recycle because it reduces my waste-collection bill and by now I have internalised the habit and its innate ‘goodness’. However, I long ago realised that it means I am also donating my time and some of my money to the cause as I wash the items in hot water and detergent to clean them first. I also fear that much of what I recycle ends up in developing nations and eventually in the ocean, where it kills marine life.

While the circular economy is a laudable goal, I cannot see how it will ever be 100 per cent. Even prehistoric man did not manage to be ‘zero waste’.

Dr Jacqueline Walker MIET

Limerick

Responsibility, not regulations, improves safety

Society is destroying itself with more rules, regulations and unproductive employment, and the UK’s well-designed and installed domestic wiring systems provide an example of ‘If it isn’t broken, don’t fix it’.

If testing involves disconnecting fixed wiring this will lead to cracked insulation and weakening of the current capacity of copper wire that often does not show up the source of a future fire. Most electricians are trained in a heated building. Domestic wiring is often installed in the depths of the winter, with sub-zero PVC cables and cold hands. Stripping the insulation becomes far more difficult and often the cutter has put a nick into the copper wire which on later regulation tests, when it is flexed, reduces the current capacity.

The most common source of failures in wiring that requires attention is the overheating 13A socket. Sockets consistently used for, say, a kettle, tumble dryer, or iron take a lot of current. The socket brass clamps that grip the pins lose their tension and the socket heats up. If you are lucky the plug feels hot and signals the need for change. No test used at present can check for this potential fire source.

The future in domestic wiring is going to be long-duration loads such as electric cars and heat pumps. Heating being the square of the current, high current for long periods could lead to many more fires. Again, regulations and inspections at intervals will not eliminate these problems.

Why are electricians skimping on the five-year testing? Because they are frustrated with the weaknesses of over-regulation caused often by knee-jerk reaction on the part of investigation teams who believe they ‘must be seen to do something’.

The UK’s talented electricians are frustrated with the current testing system as it hardly guarantees there will be no fire caused by a circuit in the next five years. The country is becoming less and less productive as a result of red tape and is heading for a huge drop in living standards. The national press could educate people about electricity far more effectively by giving examples of electric fires and why they were caused, followed up by what action the occupier should be taking.

Individual responsibility, not government regulations, will see us out of the present quagmire.

Mike Travers FIET

Saline, Fife

Tests don’t reveal hidden dangers

There have been a number of articles and letters on fire hazards associated with electrical wiring, and the importance of proper testing and documentation in E&T recently; but do these tests actually identify the hazard?

In 2003 I moved to a three-bedroom bungalow built in 1963. The previous owner had had it ‘rewired’; that is, the multitude of individual fuse boxes had been replaced by a modern 14-circuit consumer unit and the sales documentation included all the relevant electrical certificates. There was one problem: the survey showed that sometime in the past a ‘playroom’ had been created in the ample loft space, but its construction had broken every rule in the book, and I was told to remove it. There was plenty of usable space and I thought I could put in stairs, so in 2004 I contracted a reputable specialist to build a loft conversion.

When the contractors removed the floor, the wiring was exposed and I was horrified at what I found. The wiring was modern (2003) PVC with a mixture of twin and earth, singles and singles plus earth. This is very untidy but not, in itself, a hazard; however, wires were connected in open terminal blocks and in some cases just twisted together. An accident waiting to happen. This primarily concerned the lighting circuits; the power circuits were a bit better, but with a number of inaccessible junction boxes. As this was before Part P of the Wiring Regulations was introduced I was able to take corrective action to tidy the wiring and to ensure that all connections were made in proper, accessible junction boxes.

Would insulation testing, or even loop-resistance testing at the consumer unit have discovered any of these problems? How many other properties are out there with valid certificates but a hazardous installation?

Roger Edwards CEng MIET

By email

We must still meet the renewables shortfall

The November 2022 issue of E&T reported that the increase in total global electricity demand (kWh) in the first half of 2022 was met by renewables. To put this in perspective, however, on some winter days the UK’s total wind and solar power capacity in kW represents less than 2 per cent of the country’s maximum demand.

This helps to explain why we will need enormous amounts of hydrogen to be produced and stored – to meet the 98 per cent shortfall and keep the lights on when there is little sun or wind, bearing in mind that solar and wind power output averages little more than 30 per cent of nameplate (kW) capacity.

That would go some way towards explaining why National Grid ESO estimates that decarbonising the grid will cost around £3tn, or £120,000 per household. To that has to be added the cost of upgrading transport and industry.

Roger J Arthur CEng MIET

By email

February 2023 letters section cartoon

Image credit: E&T

UK metrication a ‘missed opportunity’

I was interested in Hilary Lamb’s article on metrication in the November 2022 issue of E&T. The UK government made a commitment to metrication and SI units in 1965. A metrication board was set up and substantial progress was made in the first five years. There was even a plan to metricate highway signage.

Following a change of government in 1970, the pace slackened, despite our joining the EEC. The plan for highways was put on hold. In the 1980s, unit pricing of goods was introduced to assist the consumer, but this was done in imperial terms. This was a missed opportunity; metric unit pricing would have introduced metrication in a consumer-friendly way.

From 2000, not without some pressure from the EU, metrication became compulsory on nearly all goods sold by unit quantity. In supermarkets now, nearly all merchandise is labelled exclusively in metric units.

There is a glaring exception – road signage. It is one aspect but it has a huge visual impact. The Highway Code has many references in metric, some exclusively so; the distance at which one should be able to read a number plate, for example. Public notices of roadworks give distances exclusively in metric, and marker posts alongside motorways are 100 metres apart. Yet distance and speed-limit signs continue to be in imperial.

Apparently, we are expected to estimate distances in metric though signs show imperial. On new upgrades, such as smart motorways, the new signs in the old units appear to be an anachronism. Analysis of cost of fuel for a journey is difficult. Miles per gallon is not easy now that fuel is no longer sold in gallons, but litres per hundred kilometres does not cut it either, with road distances still posted in miles.

Ireland converted its road signs on a piecemeal basis, from the 1980s, at very little cost. In due course it converted speed limits over the course of one weekend at a cost of €12m – a tiny one-off amount compared with total highways budget. Yet in the UK we still do not even have a plan.

The government consultation that opened in June 2022, eliciting views on a partial return to imperial units, closed on 26 August, but at the time of writing the results still have not been published. I can only guess what it will find, but my perception from news reports and social media is that far more oppose this idea than support it.

Other Commonwealth countries, like Australia and New Zealand, completed their metrication programmes within ten years, as was originally suggested for our own programme. The slow progress  in the UK is due not to emotional nationalism but to lack of foresight and planning by successive governments.

Denis McMahon MIET

Basingstoke

One woman deterred by 1940s attitudes

Like Rosemary Taylor (Letters, December 2022) my sister and I lived in Stockport in 1944, and my sister worked as a technician at an engineering company. After the war ended we moved to Surrey and she took a Higher National Certificate course and started work as an engineer. However, she found the sexist behaviour of her male colleagues so unacceptable that after a short time she was glad to take a job as a draughtswoman and to forget work as an engineer. I hope that nowadays women engineers receive better treatment.

John Little MIET

By email

BBC’s Flying Scotsman first

King George VI’s coronation in May 1937 was not the BBC’s first television outside broadcast, as claimed in ‘BBC Broadcast Tech: Then and Now’ (December 2022), though it was probably the first significant one. Before that, the Flying Scotsman locomotive, LNER 4472, was brought up to the small terminus then behind Alexandra Palace in London. A camera was brought out on a long lead and a programme broadcast.

John R Batts

Banbury

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