Handy electricity grid decision tree for clueless policymakers

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At the time of writing, it seems that the present Prime Barnacle has finally been dislodged, or at least has admitted his intention to allow himself to be detached from his rock in the autumn. His successor will need to look at the UK’s electricity grid as, I think, their number one priority. The problem with our electricity supply is that after a long time when its utility was measured by the entirely rational benchmarks of how reliable it was and how cheap it was, along came a third quality which was a) not related to its utility at all and b) was unfortunately orthogonal to the other two. I speak of course of the electricity supply’s carbon dioxide emissions, in the pursuit of the Avalon of Net Zero.

The introduction of the third quality could be absorbed for a time, just as a branch can absorb being sawn through for a time. It is however obvious to everyone with a dozen or more firing synapses left that the UK electricity grid has now been sawn through to the extent that only desperate propping up is holding it together.

A new PM will have to decide whether to keep sawing merrily away at the same time as hiring workmen to prop up the branch he or she is sitting on, or instead put in place a stable and reliable system. With that in mind, I provide a handy decision tree to help them figure out which kind of generator they should choose to expand the use of.

Can’t get there from here?

The system is already a mess and unravelling it will not be straightforward. What follows is therefore naïve and wrong. It generally reduces what is now a complex mix to a far simpler system. Nevertheless, it’s a starting point.

Coal

Coal produces carbon dioxide emissions when burnt. It is the archetypal “dirty” fuel. However, its emissions of actual pollutants are no longer significant hindrances to its use. Because it has a massive spinning turbine, a coal-powered generator contributes to grid stability. Fuel is easily stored in massive amounts in special organic batteries, known to energy specialists as “heaps.” In countries with coal reserves, generation can be sited to minimise transport emissions and costs. At the same time, generators can be placed close to industrial sites, thus minimising transmission costs and losses.

Even if you don’t think you need your old coal-fired power stations, you should retain them. Do not be gleefully blowing them up as if you are defeating a vile enemy.

Coal is clearly the cheapest and best option for reliable electricity, unless you must create electricity without creating carbon dioxide.

Trilemma qualities: Cheap, Reliable, Net Zero

Nuclear

Don’t worry about nuclear waste! The principal concern for waste is not the ability to store it, but the fact that it will remain hazardous for many decades. A constant expense will be necessary to monitor the waste. Nuclear has a number of obvious properties in its favour. It produces no carbon dioxide in the operational phase, if you care about that. Its spinning turbines contribute to grid stability. It has a very high energy density in terms of its physical footprint and in terms of fuel: a small amount of uranium goes a very long way, thanks to the large amounts of energy contained in atoms (against which the chemical energy of combustion is, by comparison, tiny).

Unfortunately, the constant opposition to nuclear has made it more expensive. The consequence of Sizewell B’s opposed and very protracted birth was a hiatus in new construction (made almost inevitable by a pincer movement from the “dash for gas”). Engineers retired or left the profession, so that in the UK at least, any new construction had to come from a standing start rather than from an overlapping conveyor-belt series of new plants.

New plants are generally individually engineered one-offs, which makes them prohibitively expensive. Modular construction, where new generators are nth of a kind rather than 1 of a kind, would improve this situation. New coolants have the potential to greatly reduce long-term waste.

A problem is the lack of flexibility, because current nuclear technology works best when run flat out. Therefore, the most you would want in your grid is the minimum baseload you require. That means you need another dispatchable generation technology to provide the difference between the minimum baseload and the maximum demand.

Trilemma qualities: Cheap, Reliable, Net Zero

Wind and Solar

Both wind and solar power have the advantage of not emitting any carbon dioxide during the operational phase. However, they both have a number of critical weaknesses that discount their large-scale use unless the alpha and omega of your policy is to be the absence of CO2 in electricity generation.

Both kinds of generator are weather dependent. Because the weather is erratic, so is the electricity produced by these generators. This obvious point has been overlooked by many of their advocates. They are very low-density power sources, and therefore you have to cover very large areas of land or sea with them to provide significant contributions to a modern civilisation. For wind, the most important resources are distant from population and industrial centres, necessitating long and expensive distribution networks. Solar generators have to compete with other uses for limited land space. Thus, we see prime cropping areas converted to low-power, intermittent electricity generators.

Neither generator contributes to grid stability. The more of them you add, the less stable your grid will be. They are the very definition of parasites.

Wind and solar on their own are a perfect choice if you want expensive and intermittent electricity.

Both generators are likely to be manufactured in other countries, because it is cheaper to manufacture them there. In fact, the higher the proportion of wind and solar in your grid, the less likely your country will be able to manufacture anything competitively.

Wind power will kill otherwise protected birds, so you will have to issue derogations for such generators.

To a very small extent,  the generation profiles of wind and solar are complementary, with production peaks at different times of day and/or year. Do not plan on this making anything other than a trivial difference to how unreliable they are.

Were it not for the “climate emergency”, neither wind power nor solar power would have been more than token presence in the electricity mix. That’s because they aren’t very good.

Trilemma qualities: CheapReliable, Net Zero

Heath Robinson

If you are determined to have carbon-dioxide-free electricity, have a poor hydropower resource, fear nuclear, and still want to keep the lights on, Heath Robinson is the generating strategy for you.

It’s built on the “green” technologies of wind and solar power, but instead of letting the lights go out when the wind doesn’t blow and/or the sun doesn’t shine, Heath Robinson has a large array of ingenious and expensive devices bolted onto the grid to keep it going.

You’ll need to build giant flywheels whose inertia can stabilise the grid frequency (in future times people will gaze in wonder at their rusting hulks and ask one another: what were they thinking? You’ll also need millions of batteries to store thousands of GWh of energy.

If you build out enough wind and solar to power your entire grid some of the time, you are likely to have excess energy quite a bit of the time as well. In an ideal world this excess could be diverted to useful work, e.g., production of hydrogen. But this is likely to be an inefficient process, and the storage and use of hydrogen as an energy carrier is not straightforward.

It might be useful to put in a large order for exercise bikes and distribute them to the public. Dynamos can be attached so that when the lights go out, as they inevitably will, your public will be able to turn them on again with a bit of exertion. As a bonus, cycling will keep them warm, so they won’t miss the lack of central heating. And as a double bonus, it will be great for their hearts, thus saving the NHS money.

Trilemma qualities: Cheap, Reliable, Net Zero

Renewables plus Gas

If you end up in the cul-de-sac called “Wind and Solar”, do not despair. There is a way out, and it’s called gas. You’ll need enough gas power to energize the entire grid, i.e., as much as if the wind and solar generators weren’t even there. But some of the time the gas-powered generators will sit idle. Naturally, this will add to their costs, but it doesn’t matter, because you’re not paying, eh? When the gas plants sit idle, not much gas will be being used, but the turbine will have to be kept spun up. That way it can respond quickly to lulls in the wind or the appearance of oppressive clouds, as well as contribute to frequency stability.

It’s a win-win, except the addition of all those weather-dependent generators means you now have a grid that is probably five times bigger than it needs to be.

Trilemma qualities: Cheap, Reliable, Net Zero

Hydropower

If you have suitable terrain, this is an almost perfect source of electricity. If you do not, you can only look wistfully across the sea at those who do. Or maybe invade them?

There is no carbon dioxide emitted during generation. Electricity produced is reliable and on demand, and the inertia of the spinning turbines contributes to grid stability.

Prolongued droughts and/or long periods of excess demand can undermine electricity availability. Hydro is weather-dependent, but with a large buffer, unlike wind and solar which are affected by moment-to-moment variations in the weather.

Production may be distant from point of use. Large amounts of concrete may be needed. If dammed rivers flow into other countries, there may be geopolitical considerations from reduced or less variable water flows there.

There may be ecological concerns over migratory fish.

Trilemma qualities: Cheap, Reliable, Net Zero

Gas

Gas-fired power stations are reliable, produce dispatchable electricity and contribute to grid stability. Negatives are the carbon dioxide emissions and the lack of easy storage. Transport via pipeline is relatively easy compared to the transport of coal (remember, wind and solar have no fuel at all). The ease of transport makes gas an ideal fuel for distribution to homes for domestic hot water. It is so good at that job that it may seem wasteful to burn it for electricity, but the amount used in heating is far greater.

The UK’s North Sea resource may be dwindling, but there is potential for fracking to recover large amounts of gas from the Bowland shale. Alternatives to domestic sources include nearby dictatorships.

Gas power would complement a baseload of nuclear.

Trilemma qualities: Cheap, Reliable, Net Zero

Conclusion

There are no easy answers. But there are obvious ones.

via Climate Scepticism

July 7, 2022