UK Energy Policy
I suspect that the phrase ‘UK Energy Policy’ might well be an oxymoron. With the exception of subsidies given to wind farms, there is little to suggest any sort of comprehensive plan.
Here are some statistics that I find uncomfortable. Yesterday at various times, natural gas provided more than 50% of UK electricity power generation. Since the demise of coal, combined cycle gas turbine (CCGT) generators provide the lion’s share of UK power needs. They are efficient—up to 60% is claimed; the gas turbine exhaust heat is used to generate steam, which drives steam turbine generators—and notwithstanding the CO2 emissions, CCGT is relatively clean. They can also be started up in half an hour or so in order to meet rapid variations in demand.
So far, so good. But natural gas is a fossil fuel, and there are proven world-wide reserves of gas that will last for only slightly more than 50 years at current consumption rates. Undoubtedly more will be discovered, but the bad news is that more than 40% of known reserves lie in Russia and Iran, with Russia holding more than 24%.
Even the most liberal of observers could hardly claim that either country is a friend of the UK, so there must be a major question of security of supply; more than 50% of our gas is imported and our own natural reserves are now substantially depleted. As I remember well during the oil crisis of 1973, the OPEC countries increased the price of oil by 400% and the price of petrol at the pumps more than doubled within a few months.
It seems to me that natural gas may well be a strategic weapon of the future. Economies are based on the availability of electricity, and without gas to heat our homes and offices … True, there is a plan to phase out domestic heating with natural gas, and 30-40% of consumption is used for that purpose. I do wonder though at the reality and cost of replacing 22 million gas boilers over the next ten years. I suspect that, with a few exceptions, only new homes will be fitted with alternatives.
Nuclear power will not come to the rescue either. Hinkley Point C is enormously expensive although it is planned to provide 7 - 10% of our ‘current’ power needs, and there has been a shambles over financing and planning. Frustrations with financing have caused Hitachi to pull out of two new UK nuclear projects in the last few months. It is tragic that the UK, which produced the world’s very first commercial nuclear-powered electricity generation, is now not only dependent on imported technology, but seems unwilling to pay for it. And there is always the problem of security against hostile action. In these days of state-sponsored terrorism, anything is possible. A single, well-placed, air to ground missile could easily take a nuclear power plant off line for months, years, or for ever. Not even a missile would be needed. Remembering Chernobyl, what manager would risk operating a nuclear plant that had been damaged, no matter how slightly.
There is one more problem for future electricity generation that I suspect might be the elephant in the room. Within ten years no new petrol or diesel cars will be sold in the UK. All those new electric cars and other vehicles will need electricity. Apparently there are now in excess of 40 million cars, vans, busses, and lorries on UK roads. That is potentially a lot of extra electrical power needed in coming years.
The answer seems so burningly-obvious to me, that I wonder why we are not doing it already. One of the real successes of green energy policy, has been the proliferation of wind turbines. People moan that they are unsightly, although most are situated offshore. Others moan that the operators are sometimes paid not to generate electricity, but if that is the case, it is because they are flexible, and no-one yet has come up with an effective way of storing large amounts of electrical energy when generation exceeds demand. The main drawback of wind turbines is uncertainty in the wind. The website gridwatch.co.uk indicates how different technologies—nuclear, wind, solar, hydroelectric, CCGT etc.—contribute to UK power demand. Over the last few months, I have seen wind power provide from 40% of the country’s entire electricity needs, to just a few percent, entirely depending on the weather.
The one resource, untapped, eminently renewable, entirely predictable, distributed all around the country, and needing technology that has been mature for decades, is tidal power. The tides rise and fall twice every day. There is a monthly variation according to the disposition of the sun and moon, but that amounts to only 30% or so, and can be predicted with a high degree of precision. Furthermore, the time of high tide varies around the country.
The process is simplicity itself—and has been used for hundreds of years to power the milling of corn. Build a lagoon, and install turbine generators in the wall of the lagoon. As the tide rises, the water flows into the lagoon through the turbines and generates electricity. As it falls, the water flows out of the lagoon and generates electricity. In practice, sluices are closed at the beginning of the rise and fall to allow a head of water to build up; this reduces the availability of power generation to around 14 hours in every 24. But since there is always high or low water somewhere around the coast, careful positioning of generator sites could provide full, uninterrupted coverage.
There could be a further benefit. Much of the east of England, particularly Essex and Suffolk, is sinking into the sea. Since I lived at Wivenhoe on the Colne estuary in Essex in the 1970s, the sea-level has risen there by 40 mm. The cost of coastal protection is high and some say ultimately a waste of effort, since eventually the sea will overtop any man-made defences. But a tidal lagoon doubling as coastal defence would change the economics completely. Might this be an answer to the east-coast problem?
No-doubt there are some defects in these arguments, but I am certain that the basic principle is sound: renewable, relatively low tech, and distributed power generation, with added benefits, as part of future energy policy. Isn’t this exactly what the country wants right now? A massive infrastructure project providing employment for tens of thousands, and a real strategic asset for the whole country.
11/12/2020 09:46:44 am
Quite right, and since you're up against the petro-chemical/fossil fuel lobby, completely unthinkable. Also, using tidal power slows the Earth's rotation, although I don't think that our generation need worry unduly about the immediate effects of that one. I could see it as a tabloid headline however....
11/12/2020 11:26:02 am
I did worry about that a little, but since the energy locked up in the rotation of the earth, and of the moon around the earth, is two to the power of my overdraft, I think we're safe for a few hundred million years.
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Welcome to the Mirli Books blog written by Peter Maggs