1.4GW !

Some solar panel farm owners have made no secret that their panels and battery combinations are to fill in the short(ish) periods when demand is high, and so is the (spot) price for buying in extra electricity. There is not necessarily anything wrong with maximising revenue by either generating and storing your own electricity or buying it in cheaply during off peak, storing it and then selling it back to the grid when the price is at a premium. This kind of operation is much the same as pumped storage.

I wonder how sustainable is this business model? As more of these facilities get built there may become a glut of excess electricity available to meet short term demands and there will not be premium prices paid. Is a solar farm viable when competing with other methods of generation when just supplying the base load? I'm excluding domestic solar feeding back into the grid as in future any capital investment would be by the householder.

Are the costs of generating by (commercial) wind and solar fiddled by the sale carbon offsets? Generate 1kwh of electricity by wind and have a

Do they get any subsidies for putting kit like this in? No problem with this if they installed it entirely at their own expense. Then they are helping to even out prices and supplies without it costing the taxpayer or consumer.

I also observe the main Comment piece in the Times today. This points out that Millibean's insistence on no more new oil/gas is going to have us ending up with no power. The writer has also taken on board the issue of the calm winter periods, and that wind is not necessarily the cheapest, and that you have to fudge the figures to make it so. Quite an eye opener, should provoke some reaction amongst the faithful.

The item says, IOW, a number of things that some of us have been saying for years.

That last line to me looks like a big clue guys that he might just be joking a little...

Andy

I think you may find that some of that waste is just slightly related to the nuclear weapons programme.

Andy

On 17/07/2024 17:52, Paul wrote: <snip>> However,

Presumably you are referring to this

which I hadn't heard of. But I can't see what the lesson learnt was that you are referring to.

(I could see that it had two fires even before it was commissioned!)

Andy

I have a feeling that this was one I started with, when trying to find the largest such battery so far installed, its capacity (in Wh), and its cost. These two numbers proved hard to find, as reports about some install or other tended either just to give the cost, or the highest discharge rate.

Anyway having obtained the two figures needed, using 30GW as a sort of average UK demand, and scaling the battery up to be large enough to provide 30GW for 5 days or so, was where I got my £1000,000,000,000 cost from.

I know they produced weapons - so I suppose it makes some sense that they're involved in decommissioning. Looks to be a nasty, expensive, and lengthy (100 years+) process.

the 100 year time is what makes it simple and cheap

It's disappointing facts like these that are the reasom why ArtStudents™ Never Do Sums They just join the greens or the Labour party instead

I'm afraid that "not doing the sums" seems to be inherent in looking at renewable power. I wondered about the possibility of using EVs as convenient sources of battery power for home use. After all, we are being forced to change to EVs over the next decade or two, so why not use that "battery on the drive" for backup power?

Turns out it's not so simple to have V2G as a usable power source. And, of course, the financial considerations haven't been looked at properly. See the second paragraph here:

It's decommissioning the waste from the bomb programme which is the nasty part. That related to power station waste is easier and well developed - as was described by Prof. Sue Ion of Imperial in 2011 (2012?) on that Life Scientific R4 programme.

As I posted the other day, you store the fuel rods in tanks of water for 10 years to allow the worst isotopes to disappear altogether, then convert the remainder into blocks of glass that can be stored. This is a routine process that has been the norm for 20 to 30 years now.

Some thinking seems to based on the majority of the population living in houses with off street parking. If people happen to be living in a town or city where a lot of buildings are of certain age then there may only be street parking, and often not outside the house. Solutions that may work in a an affluent suburb may not work for many millions of others living in different accommodation. Doing the sums may indicate X million EVs in the UK each with an average battery capacity of Y equals enough backup to support the grid for a day/week - eureka we have the solution. That's not real world where, say, like a near neighbour who only plugs in about once every two weeks because they don't do much mileage for long periods of the year. The "sum" is wrong because of the assumption of how many EVs are connected at any one time. Then there is the question of who controls the backup, the householder or a third party? I'm sure that if you use your EV to commute that you don't want to come out to a drained battery before you start your journey. Do you really want a third party putting your expensive EV battery through extra charge/discharge cycles and perhaps devaluing the second hand value of your vehicle?

Should read water cooled tanks of HNO3.

I'm not talking hill farms, I'm talking arable fields growing turnips or soy. Both of which have some element of human food but I think most of it goes to animal feed.

I agree that it would be better to put solar on poor agricultural land - eg thin chalk soil. I think it's already prohibited to put it on first and second class land.

People selling combustion appliances are pushing hydrogen, but electrolysing water, pumping hydrogen through a distribution network, and then burning it, is 5-6x less efficient than a heat pump. That's a huge extra running cost to pay and one that can't really be swept under the carpet.

Even swapping a gas boiler for a resistive electric one is going to be more efficient than using hydrogen - which would require a boiler swap anyway. High temperature heat pumps (with a two stage compression cycle) are less efficient than single stage ones, but require fewer system changes - so if you're going to swap you might as well install one of those.

Not sure what you do about combi boilers though. An electric shower plumbed into every tap?

Theo

IT has gone down a little, but remember 300 GW (or 188 GW) are total input energy. They include Natural gas chemical energy, which is only converted to electrical energy at something like 40% efficiency.

I seem to recall reading we might only need an average 100 GW electricity supply. My point was we would need massive green energy generation overcapacity to cater for variation in generation supply, consumer demand and inefficiency in storing energy.

This is only the case if we don't have a proper nuclear rollout, wouldn't you say?

Yes. Nuclear is relatively straight forward to understand.

All I'm saying with regard to batteries, is they're a part (an "expense") of using randomly available or inconveniently available power sources.

If you are paying a supplier to throw away power, how is that giving the cheapest power to families ? If the amount of solar can be "absorbed" by the grid is not exceeded, then no battery is needed.

One of our power companies, puts that information right on their summary page for power sources. They indicate the maximum amount of renewable that can be "managed" on the grid (and what percentage of renewable is currently connected). No where on such pages does it say "make 100% of the power sources solar if you want, we don't care". It doesn't say that. But up to a certain percentage, it can be blended in. The number might be, say, 13%. The rest is dispatch-able power sources, dependable ones, you just order them up for the day. With such a model then, these "cheaper" wind farms, up to the 13% figure, could give you "slightly cheaper overall power for families".

But any time you choose to violate whatever the grid designer determines to be the correct mix, then you had better have done the engineering to make it work. Otherwise the stories about paying suppliers to throw away power, will persist.

Power generators, have leading and lagging phase angle. One of the two directions, is "hard on the equipment", and the operator avoids driving the equipment in that direction. By adjusting the phase angle, you can adjust the amount of power you pump into the grid. Part of keeping the grid stable then, is not ruining any generators (no matter whether they're solar inverters or wind farm interties) while doing so. Part of running a grid, is preventing it from tipping over like dominos (on overload), or damaging equipment by forcing it to operate with the wrong phase angle.

Grids don't drop too often, and ours dropped years ago (while I was still working). It was pretty funny actually. We were out of doors, playing recreational league soccer. Game was over, we're headed for the parking lot. First I hear "I don't have dial tone, I'm on Bell". Then the next guy checks his smartphone "I don't have dial tone either, and I'm on Rogers". That is the first inkling we had, that the grid was gone :-) (At the time, NONE of the cell towers had backup power. NONE.) For the next several days, there were lots of requests of POTS phone users "um, could I borrow your phone for a minute", as that was the only kind of phone which still worked. Both the CO switching offices, and the POTS phone lines, had backup power. Today, ALL the urban cell towers have backup power, even if it isn't impressive backup power (have to refill tanks regularly). The tower nearest me has a shed with a light on it, which is where the backup power is located.

And the grid is not as big as it sounds. North America consists of a number of separate grids. One of them can drop, and the other grids stay up. In Canada, there is one place, if you stand with a leg on either side of the street, "the two 60Hz are not the same". They're not synchronous.

When Texas dropped, perhaps it and Florida might be on their own grid. Or perhaps Texas is all by itself. That is one of the reasons Texas citizens suffered. If politics had allowed them to join an adjacent grid, there's a good chance nobody would have been cold or faced with a $10K power bill a month or two later.

Somewhere, where you are, there is a report which indicates how much renewable can be connected, without the usage of batteries or other schemes to smooth it out. Normally, part of the sign off for projects, would be the knowledge the grid is still being managed properly.

And you can't change a grid or a power system, over night. It takes time. And you might not even have the human capital, to make the changes (he said, looking at the activity at the local substation recently).

If we needed to do anything in society in a hurry right now, how ready are we ? My guess is, not very ready. If we needed to build up grid capacity (more wires, thicker wires), who would do it ? No, it wouldn't be the staff at my substation. Although I would give them to you for one low, low, price.

Paul