Low Electricity Demand and System Balancing Problems during The UK’s Coronavirus Lockdown

I don’t know what happens to the cost but I suspect the consumer will be in for a rude shock . If the industrial and commercial sector is not using ( and paying for the electricity the power generators will need to make up the difference elsewhere especially if the cost of running the system has gone up due to trying to deal with increased unreliability risk. At times of overall reduced demand prices should be falling just look at what has happened to other commodities especially oil.
Hopefully this experience together with the financial impact of the corona virus measures and the impact of Michael Moore’s film might cause Boris to have a policy rethink about this disastrous renewables path he is taking the UK down.

Paying renewables not generate, that is those operators have politically enforced mandates to make money for their owners. demonstrates that the climate scam was never about CO2 or climate.
Michael Moore’s unmasking the idiocy of renewables to his audience of Lefties will be ignored as well because of discomfort of cognitive dissonance it brings to his climate religion tribe.

As demand is lower, I expect to hear the pro-renewable lobby to claim loudly and proudly that the wind and solar generation is meeting and/or exceeding this demand during this crisis and this is why we need more of the same.

They will say nothing about the timing difference between generation and demand, the fragility of the system nor the overall cost of maintaining and operating such a variable source.

This is a good article but from the comments it seems that some of the important detail has not been fleshed out enough.
First of all let me say something about solar power in the UK.There is quite a lot of it, but none of it is metered centrally by the grid, and, as far as I know none of it is under central control. If you look at the demand curve graphs you will see that there is a big midday notch. I have been monitoring, via my website, Gridwatch, (https://gridwatch.org.uk) the same data as is used here, since 2011. There never was a midday notch until solar power came along, and this ‘notch’ is actually the effect of millions of domestic solar panels and a few commercial solar farms kicking in and feeding local demand. As far as the central monitoring is concerned this represents a fall in ‘seen’ demand and so ‘the notch’. A couple of years back Sheffield University, in a zeal for all things renewable, starting publishing their estimate of total GB solar power, based I think on sampling a few sites who agreed to share their output figures. I now incorporate that data with suitable caveats on the same website and database.

This solar power is absolutely ‘wild’ on the grid. As far as domestic panels go, there is absolutely no way to control the output centrally at all. I am less sure about the few commercial solar farms as to what their contractual arrangements are and whether (like wind) they can be ‘constrained off the grid’.

Wind farms are similarly wilful in their output, although both solar and wind are reasonably predictable to within a couple of GW several hours ahead, and a couple of GW is something the grid should be able to cope with – typically, if there is a massive and sudden shortfall if a power station trips out, the pumped hydro at Dinorwig and the small hydro sets get an alarm and can be up to power in seconds. So long as they can ‘hold the fort’ for half an hour or so without running out of water, that is enough to get the gas sets up and running. Similarly a sudden drop in demand is catered for by the inverse – hydro stops and then gas sets are shut down.

Contrary to popular belief not much ‘spinning reserve’ is kept online. I suspect that what actually happens is that the hydro plants are used to modulate very small and rapid fluctuations in demand over the timescale of minutes.

This however is not the instability which is the matter of concern here, what is a matter of concern is the grid frequency – nominally 50Hz± not a lot. Traditionally this was held to 50Hz exactly on average over the day so that synchronous electric clocks kept proper time, but minor fluctuation was tolerated. And a major part of that stability was inherent in the design of the generating plant – massive turbines and rotors in the alternators held to 3000rpm (for 3 pole designs) represent a surprising amount of stored kinetic energy. More than the average battery installation for sure, and in the case of – say – lightning striking a main grid link and shorting it – this is what supplies the overload current until the arc self extinguishes. Then of course we have electric trains which are constantly stopping and starting with power flows to and from the grid (most these days push braking energy back into the grid) .

This is all well and good until – because renewables have priority on the grid – there is hardly any conventional generation on the grid at all. Peak solar and a bit of wind is capable of putting over 16GW onto the grid and typically when Europe has a surplus in summer, we will be importing another 4GW via the undersea high voltage DC links. So that’s 20GW of ‘unconventional’ generation on a grid whose maximum total demand is in the middle of the day scarcely 30GW. Typically there will be a 3GW of wood burners at Drax plus about 6-8GW on nuclear power on the grid. And all the coal, gas and hydro shut down.

And this is where the problems start to get nasty. All those renewables, and the DC power under the sea, feeds the grid via inverters. Electronic circuits that chop the DC and shove it through high frequency transformers to generate an approximate 3 phase sinusoidal waveform that is fed to the grid via chokes and capacitors to improve the waveform . And this has to be in phase with the grid and locked to its frequency.
How do they know what the frequency is? They monitor it of course.

And what happens if the frequency, now hardly controlled by spinning turbines, drops due to a temporary overload?

THEY SHUT DOWN AND DISCONNECT THEMSELVES!

And instead of 2GW lost from the grid, because a reactor has tripped, that’s 20GW, and a total cascading blackout across the entire country.
That is the problem that is concerning engineers, myself included.
It’s mentioned but not explained in this report.

In between these limits, the operator must retain sufficient conventional, rotating plant to provide stabilising inertia, but also find room if required for the 23 GW of wind and 12 GW of solar power, both uncontrollable.

(I have never actually seen more than 12GW of wind , ever, and certainly not when the sun is shining, so he hasn’t got that bit right .There may be a reported 23GW of wind nameplate capacity, but at any time at least 15% is broken awaiting repairs, or constrained off, or simply not getting enough (or getting too much) wind. Yes if the wind is too strong they shut down to prevent damage)

In other words what this post is about is to explain why the operator must ‘retain stabilising inertia’ and what it is and the consequences of not doing so.

When renewable energy first came out I tried to explain the problems to people who didn’t want to listen
The first and easiest problem is power density. the late Professor David Mackay wrote the definitive book on that (which I helped him get published), called “without the hot air” which was the go-to book to see how much renewable energy there was for a given land or sea area. That alone should have been enough to condemn it out of hand as Michael Moore seems to have finally realised.

The problem he didn’t tackle, which I took on, was the problem of intermittency – that renewable energy is not only diffuse (low energy density, so needing BIG constructions over a lot of land or sea area) – but also variable Or as the term is used intermittent. Or to be pejorative unreliable.

Many ‘greens’ think the problem is one ofpredictability, but it isn’t, Whether you know in advance whet the sum will shine the tides will come on or the wind will blow is not the point. It’s having to start up a gas set when they don’t, and the excess of gas that it uses, which partially negates the carbon gains from not using it for 6 hours and letting it cool down, but also requires that you build an maintain the gas sets which are now runs so rarely that the capital cost of them and the necessary maintenance and staffing is not longer paid for out of generation income, so you have to start charging more money…and that as Professor Hughes pointed out, you end up in the situation where instead of nice (but expensive) efficient CCGT stations the temptation is to build cheap OCGT sets that use nearly twice the gas, or even worse, in the UK case, Diesel sets, because they are the cheapest to put in if you are only ever going to use them a couple of days in winter. Add in the carbon cost of building windmills on massive concrete pylons, and really – and this is borne out by total emission figures – there is no net carbon gain from renewables at all in the UK. Only where you have hydro power to offset, can you really make wind and solar work to reduce carbon emissions. And Britain does not.
Plus the fact that renewable energy has high peak to mean flow, you need to build expensive grid links to e.g. Scottish offshore power stations to transport the peak flows to the urban centres in England, but when the wind stops blowing these are idle. More expense for no return.

Renewables themselves by themselves may be cheap, but the cost of making them reliable and delivering them to the consumer is very expensive.

So that was the two reasons why renewables were pointless, the third one, why they are in fact actively dangerous, is what this article is all about, coincidentally exacerbated by the COVID19 lockdown and concomitant low demand.

(And whilst hospitals may have emergency generators, losing grid power is not something that happens without cost there, either)

What the current move to put batteries on the grid is all about is not keeping the grid alive when the sun goes down and the wind stops blowing – that is truly beyond any battery – but to provide active frequency stabilisation in the event of overload. Again, what was built in to conventional power stations has to be added to renewable generation ( increasing the cost and carbon cost and pollution cost), to make it work properly.

To summarise:
Renewable energy must always use a lot of real estate and have a negative impact on the environment because its source energy is diffuse. This makes it expensive.

Renewable energy alone is either inadequate (biofuel, hydro) or intermittent, and therefore must always be supplemented by another form of energy adding considerably to the overall cost of energy and negating its effect on CO2 reduction. In addition grid links must be uprated to carry peak loads or the wind companies paid not to generate them. The consumer pays. The renewable companies do not.

Renewable energy alone is unable to provide grid frequency stability because it has no stored rotational energy: So that too has to be bolted on (using batteries?) again at increased cost to the consumer (but never the renewable operator).

In short, when you hear someone declare that renewable energy is cheap, ask them who pays for its impact on the grid?