Navitron Renewable Energy and Sustainability Forum

General Renewable Topics => General Discussion => Topic started by: nowty on June 13, 2018, 10:41:48 PM



Title: Gridwatch Overnight Tonight 14/06/18
Post by: nowty on June 13, 2018, 10:41:48 PM
How low is gas going to go overnight with storm Hector boosting wind generation ?

Gas currently 7.7GW @ 22:40 with wind at 7.6GW.

With about 5GW of demand to drop off and wind probably going over 10GW gas is going to be near zero in the small hours.

And tomorrow its still going to be windy with quite a bit of solar so maybe another record gas low in the daytime too.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: dan_b on June 13, 2018, 10:46:09 PM
Gas has dropped to 6.1GW (22:50) but there’s still 0.5GW of coal on the grid?  Weird!  Mind you Biomass has dropped back to 1GW too - it’s normally almost always higher than that


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: knighty on June 14, 2018, 12:38:33 AM
coal 0.26
nuke 7.3
gas 4.73
wind 7.68


12.46am

:-)


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: MeatyFool on June 14, 2018, 02:58:19 AM
Coal .48
Nuke 7.54
Gas 3.78
Wind 7.62

03:06!

Meatyfool..


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: oliver90owner on June 14, 2018, 06:52:36 AM
I think they would keep some gas running at all times.  Wind generation may well need to be curtailed for this to happen but they need some form of frequency control and fast response generation, should the high winds speed close down a large wind farm, for example. 

Pumped storage would be filling on cheap energy and would not wish to generate at such periods.

It is a balancing game - whether to keep gas as spinning reserve only or to make some power.  It costs money to maintain the grid in a state of readiness, one way or another.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: oliver90owner on June 14, 2018, 07:06:52 AM
Doubtless(?) some journalist will soon be spouting about a new record for wind production - continuously exceeding gas generation for more than eight hours...


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: brackwell on June 14, 2018, 07:29:48 AM
Wind was probably curtailed last night  https://www.bmreports.com/bmrs/?q=generation/windforcast/out-turn

Prices went negative and the French and Dutch interconnectors went negative.  https://www.bmreports.com/bmrs/?q=eds/main

The lowest i have ever seen the gas go was  1.2 Gw about 5yrs ago and coal went about the same.   Interesting they are keeping the coal spinning in rediness but they get special payments for this.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: dan_b on June 14, 2018, 07:34:45 AM
Wind definitely curtailed - this from EnAppSys on Twitter

As the wind generation builds this evening it is highly localised with 5GW in Scotland stuck behind the various Scottish constraints. Almost 3GW being bid off at an average of £70/MWh and Foyers and Cruachan absorbing power for free. enrenew.netareports.com/#gbwindbylocat… ^PH


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: GarethC on June 14, 2018, 07:47:00 AM
So when more inter connectors are built, international and to Scotland, there will be much less curtailment in times like this?


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: M on June 14, 2018, 07:51:19 AM
So when more inter connectors are built, international and to Scotland, there will be much less curtailment in times like this?

Yep, and the steady deployment of storage and EV's that should prove to be very complimentary and timely.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: M on June 14, 2018, 07:52:11 AM
Just updated Gridwatch and coal has gone zero.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: linesrg on June 14, 2018, 08:17:42 AM
So when more inter connectors are built, international and to Scotland, there will be much less curtailment in times like this?

As I've recently commented I understand the need for more interconnectors but have a different view when it might mean having one as little as 0.6km from our house!!!!!!!

Have charged the Zoe here at home overnight - a mere 38.7kW.

Regards

Richard


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: nowty on June 14, 2018, 08:45:09 AM
I'm guessing that wind must have been curtailed because it only peaked in the early hours at around 8GW, hardly up from earlier in the evening. Gas bottomed out just under 3.5GW.

Octopus Energy has an Agile tariff which occasionally (like twice per year for a couple of hours) pays the customer to use energy. I wonder if last night was one of those times.

I still reckon we might break a weekday record this afternoon if the sun comes out.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: dan_b on June 14, 2018, 08:59:44 AM
They could have done with the Western Link being up and running at full capacity last night - that was the whole point of that link wasn't it, to reduce/avoid curtailment ?


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: dan_b on June 14, 2018, 09:03:42 AM
This is frustrating and never noticed this before, but the Crown Estate Asset Map for UK wind doesn't actually include the Scottish windfarms.

http://www.thecrownestate.co.uk/en-gb/our-places/asset-map/#tab-2


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: dan_b on June 14, 2018, 12:56:42 PM
Lowest ever working weekday carbon intensity on the UK Grid. Last record was 108 gCO2/kWh 11:30 7th June 2017 and it’ll probably go a little lower still.



(https://s22.postimg.cc/bymlox5q5/carbon.jpg) (https://postimg.cc/image/bymlox5q5/)


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: M on June 14, 2018, 01:20:04 PM
Well that's jolly good news old chap!  exhappy:


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: gnarly on June 14, 2018, 01:59:46 PM
Also just spotted this which is a forward prediction of carbon intensity... for next 96 hours !  Has an API too

http://carbonintensity.org.uk


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: MeatyFool on June 14, 2018, 02:16:51 PM
just installed the app dan_b uses - first result 91 gCO2/kWh!!!!!

70.7% top three sources (non-FF, wind, nuclear, solar)

Meatyfool..


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: phoooby on June 14, 2018, 03:24:44 PM
That carbon intensity link above is good. South West region is currently 2g co2 per kWh !. Mostly solar, wind and nuclear, with 0.8% gas. Very impressive !


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: djs63 on June 14, 2018, 03:36:12 PM
The north east data is very similar to phooby’s south west. Bit cheesed that so much electricityis coming from nuclear which produces a bit less CO2 but has other problems sh*tfan:


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: dan_b on June 14, 2018, 03:46:18 PM
Seeing as we've got them we might as well keep using the nuclear plants, surely?

I'm not sure if this App accounts for embedded wind in its calculations?


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: azps on June 14, 2018, 07:29:06 PM
Seeing as we've got them we might as well keep using the nuclear plants, surely?

Well, maybe. Let's think about the economics. How much does it cost to produce one marginal unit of nuclear electricity? Based on the plant has been dropping off the US grid because it can't compete with gas, about £20/MWh. So far so good, that's pretty cheap. Now we just need to add in an estimate for the third party liability risk. Now, that's highly uncertain, but based on the work of a German specialist in scientific advice to the insurance industry, Versicherungsforen Leipzig GmbH, it's in the range €2011 140-6730/MWh. Let's take the bottom of the range (even though UK plants are now quite old and have known problems such as the graphite block cracking). That puts our estimate of the social cost of nuclear at at least £140/MWh. There's all the waste and everything too, but already we can see that even with a carbon price of £150/CO2e, gas still looks better than nuclear.

So, economically, it probably is more efficient to close down the nuclear plants now, if we will substitute them with gas in the short term, and renewables within a year or two. How quickly could we build say 10 GW of onshore wind and 10 GW of PV? Probably 2 years. So really, yes, we should be telling nukes now to wind down, no more refuelling (which gives them a 6-18 month life expectancy or so). And get on with building renewables at full pace.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: djs63 on June 14, 2018, 08:45:51 PM
Yes we should go for renewables quickly but do we also need storage even on a daily basis?

PV presumably potentially peaks at midday though it depends on clouds etc which does not coincide with evening peak demand. Wind is variable. Yes to renewables but need a smoothing system.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: phoooby on June 14, 2018, 09:08:55 PM
Add the economic cost of £20 to the social cost of £140 per MWh gives a figure higher than the tidal lagoon which has equally reliable and predictable output.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: desperate on June 14, 2018, 09:46:46 PM
Seeing as we've got them we might as well keep using the nuclear plants, surely?

Well, maybe. Let's think about the economics. How much does it cost to produce one marginal unit of nuclear electricity? Based on the plant has been dropping off the US grid because it can't compete with gas, about £20/MWh. So far so good, that's pretty cheap. Now we just need to add in an estimate for the third party liability risk. Now, that's highly uncertain, but based on the work of a German specialist in scientific advice to the insurance industry, Versicherungsforen Leipzig GmbH, it's in the range €2011 140-6730/MWh. Let's take the bottom of the range (even though UK plants are now quite old and have known problems such as the graphite block cracking). That puts our estimate of the social cost of nuclear at at least £140/MWh. There's all the waste and everything too, but already we can see that even with a carbon price of £150/CO2e, gas still looks better than nuclear.

So, economically, it probably is more efficient to close down the nuclear plants now, if we will substitute them with gas in the short term, and renewables within a year or two. How quickly could we build say 10 GW of onshore wind and 10 GW of PV? Probably 2 years. So really, yes, we should be telling nukes now to wind down, no more refuelling (which gives them a 6-18 month life expectancy or so). And get on with building renewables at full pace.

Shouldn't we be comparing that social cost of nuclear with the social cost of dumping all that co2 into the atmosphere. Serious question here,what would the likely insurance premium be against the climate going a bit nuts?

Desp


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: Philip R on June 14, 2018, 11:16:43 PM
azps,
Your accelerated nuclear closedown proposals are very dangerous. Increased CO2 emissions, higher gas and electricity prices,  less diversity in the uk Electricity supply, and greater reliance on some tenuous gas supplies. All in all heading for a nationwide grid system failure.

I believe the climate change panel recommendations put a massive cost to society if climate change accelerates.

Philip R


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: azps on June 15, 2018, 01:30:01 AM
Shouldn't we be comparing that social cost of nuclear with the social cost of dumping all that co2 into the atmosphere. Serious question here,what would the likely insurance premium be against the climate going a bit nuts?

Definitely: that's why I included a carbon cost of £150/tCO2e. Estimating marginal social damage cost of carbon is difficult, but a range of £100-£200 is in line with the upper numbers in the literature. If we were talking about long-term increases in emissions, that would be a serious problem. But we're not. We're talking about a very small number of gigawatts of emissions for a couple of years.

As for Philip R's "nationwide grid system failure", no, not at all. Plenty of countries manage perfectly well without any nuclear and don't have this nationwide grid system failure. Higher prices? Well, that's a question of how the costs are allocated. As I tried to show with the calculations above, there is a net gain in economic efficiency from a phase-out of nuclear and a corresponding ramp-up in renewables. That means a net economic gain for the country. Does it mean increased gas consumption? Well, with the renewables getting built at about the same rate as the nuclear is decommissioned, then no, it doesn't. However, even if it did mean burning a bit more gas for a couple of years, the cost calculations are still favourable.

Yes, that certainly should set some alarm bells ringing: can it really be true that the marginal liability costs of nuclear are so large that they become larger than the marginal damage costs of carbon from burning a bit more gas? It does depend on a whole bunch of things that we have very limited information on, which means there is very high uncertainty on it. Crucially, what is the probability of a UK nuclear accident of the scale of Fukushima or Chernobyl? NB this is not asking what are the chances of identical accidents of either (negligible); but rather, what are the chances of a release of radioactive material through any cause on that scale (non-negligible)? And if it were to happen, what are the odds that the material would end up on economically productive parts of the country, rather than (as happened after Fukushima) there being incredible good luck (after the terrible luck of the earthquake & tsunami) that resulted in almost all of the airborne material being blown out into a gigantic ocean where it was very quickly diluted and carried away from detectable harm. Because had those winds blown in another direction, towards Tokyo say, then the Fukushima nuclear disaster wouldn't have cost a mere £100-200 billion or so, it could have been ten or fifty times higher. And that's how the liability costs risk become inordinate. That's why no sane insurer would dream of taking on that risk. And if they wouldn't, why should the taxpayer do so?

Regarding phoooby's point: I think the lagoon is still the wrong answer, because it's more expensive than onshore wind or PV, and is unlikely to produce as much power as our remaining nukes. Tidal barrages across all our major estuaries could produce mean power of that order (I reckon around 5.6 GW for England (https://claverton-energy.com/tidal-barrage-potential-in-england.html) plus some for Scotland), but that would be a 10 to 20-year project to build them. Now, I think we probably should build them (we'll need the barrages for flood protection from rising seas anyway, so may as well make them generate power too), and we should start now, but that's a little too slow to help with the economic inefficiencies of keeping our old nukes running.

For djs63's question: yes, we do need additional support for things like frequency reserve and storage: and what we've learnt from the recent capacity & frequency auctions is that building that stuff is much cheaper than most of us had dared to hope for. So right now, the marginal costs of wind and pv intermittency on the British grid are very low.

One way to balance out all these trade-offs is to structure the market so that it can discover an efficient allocation. That means taxing fossil fuels at the upper end (because of the asymmetric risk) of their marginal social damage cost; and taxing nuclear at its marginal social risk cost. I'd expect that we'd see is both fossil fuels and nuclear vanishing off the grid fairly promptly, and renewables getting built far faster than we've seen to date. Yes, that would definitely make the cost of energy shoot up for a while, until the substitutes were built. It would also bring in huge amounts to the exchequer which could be distributed back to citizens and non-energy businesses, thus leaving them no worse off on average. And it would mean that many energy-efficiency measures suddenly become a lot more viable economically.

A


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: M on June 15, 2018, 07:30:19 AM

One way to balance out all these trade-offs is to structure the market so that it can discover an efficient allocation. That means taxing fossil fuels at the upper end (because of the asymmetric risk) of their marginal social damage cost; and taxing nuclear at its marginal social risk cost. I'd expect that we'd see is both fossil fuels and nuclear vanishing off the grid fairly promptly, and renewables getting built far faster than we've seen to date. Yes, that would definitely make the cost of energy shoot up for a while, until the substitutes were built. It would also bring in huge amounts to the exchequer which could be distributed back to citizens and non-energy businesses, thus leaving them no worse off on average. And it would mean that many energy-efficiency measures suddenly become a lot more viable economically.

A

The problem here is that the cost savings are hidden, since they are either paid via general taxation, such as NHS costs, AGW mitigation, insurance/liability, whilst the RE costs are highly visible and slapped onto the energy bills via the green tariff.

For the majority of the public, a shift from the hidden to the visible will yet again convince them that RE is pushing up costs. My position is simple, all RE subsidies are a result of FF costs, therefore they are not RE costs, but FF costs, but try telling that to someone complaining about the bills going up.

I'm not against what you are saying, I support it entirely, just pointing out that the 'big picture' is not one that many bill payers are interested in looking at, sadly. It's far easier to blame the 'greenies'.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: dan_b on June 15, 2018, 07:52:03 AM
Thanks for the detailed responses there - good insight and some key issues raised I’d not thought about.

On the flip side, UK wind has gone from a curtailed 13GW to 4GW in the space of 24 hours and last week was basically at zero for a couple of days.  As we continue to add wind capacity those peak and trough deltas are only going to increase - do we really have faith that sufficient storage capacity can be built at a cost that doesn’t then make wind massively costly again?


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: oliver90owner on June 15, 2018, 08:07:26 AM
AZPS,

Sorry but something flawed here.

Another 10GW of each of wind and solar is a drop in the ocean.  Only a week or so ago the wind generation was down to 50MW (according to gridwatch).  No solar in the dead of night and minimal in the depths of winter.

Supplying summer midday demand with wind and/or solar might be one thing but reducing carbon intensity throughout the year would not occur by closing down all the nuclear plants in short order.  Need a lot more storage and a lot more renewable generation for that to occur.  But let’s get on with it and climb out of the fossil burning and nuclear options.

Tidal generation would be better - at least it is predictable and covers most of 24 hours.  Lagoons or flow, it matters not.  Cost of storage needs to be included for solar and wind generation, of course.  But a zero CO2 intensity is still a good target to aim for.  Then close down the nuclear facilities as and when possible.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: brackwell on June 15, 2018, 08:37:59 AM
At the moment wind is "having its cake and eating it".  Due to the merit order effect wind and solar generation gets a kind of priority which at present levels is fair enough. However as the RE increases its gets paid for curtailment, has as just happened.  This in my opinion is a burden on the consumer and needs to stop immediately. This curtailment needs to be considered as part of the investment decision.  Investment will then continue until a balance point is reached where CF (capacity factor) is balanced against cost as an investment decision/calculation.  The tech guys will then develop ideas to use the excess to increase financial returns such as colocating wind with sun with storage with gas production etc.

Who knows how far down the line this development would go coupled with changing demand times,smart meters,EV charging and V2G etc.

Ken


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: azps on June 15, 2018, 09:24:12 AM
Another 10GW of each of wind and solar is a drop in the ocean. 

It's about 3.5 - 4GW of clean power on average. That's about 10% of electricity supply. Our nuclear fleet is aging, in decline and shutting down. Over the next few years, it's going to average about 10% anyway.

Quote
Only a week or so ago the wind generation was down to 50MW (according to gridwatch).  No solar in the dead of night and minimal in the depths of winter.

Yes, they're exogenously variable. And, the costs of managing that variability are now very low, as we've seen in the capacity auctions and the frequency-reserve auctions. And new transmission capacity is relatively cheap too.

Quote
Tidal generation would be better - at least it is predictable and covers most of 24 hours.  Lagoons or flow, it matters not.

Oh, it really does matter: lagoons do little or nothing for flood protection. If we build lagoons, and then have to build barrages outside them, it's going to be an deeply inefficient use of resources.

Quote
But a zero CO2 intensity is still a good target to aim for.  Then close down the nuclear facilities as and when possible.

The UK's old nuclear plants will be closed long, long before that. While the UK continues with its nuclear vanity projects, that sends a strong negative signal to renewables investors that they can and will get sidelined whenever the government feels like it, in favour of more expensive nuclear projects. And that negative signal means that investors require higher returns, pushing up prices. That's why Germany's signal to investors in 1999 that nuclear was being phased out, was so important, and so effective in getting huge amounts of capacity built, and getting lots of investment in wind & PV manufacturing.

On brackwell's point re renewables getting paid to generate and to curtail: well, yes - all other generators are eligible for those payments too, so I don't see any reason why renewables should be excluded from them. Wind, when generating, can be an amazingly fast responder to changing demand - that's a valuable service, and it should get paid to provide it, just as gas plants do. A lot of the time wind can do it better than gas can, too. We're just starting on a big transition. Existing markets certainly aren't fit for purpose any more. There will be a short period when we over-pay for ancillary services, in order to stimulate the innovation needed (and given how low the prices are in those markets, the over-payment isn't onerous at all). That's a good thing, as long as it's only a temporary circumstance. The sort of negative prices that Germany and Denmark see are a good thing: they're stimulating innovation in demand response, storage, and a bunch of other things. We'll know when there's been enough innovation, because the negative prices will shrink away, as long as we've restructured the markets to enable the demand-side to express itself fully.

I've no wish to gloss over the exogenous variability of wind and sun. They're big and interesting challenges. We know we've got solutions for them. We don't know what the most cost-effective mix(es) of solutions look like yet, and to a very large extent, we're only going to discover that by asking the market. We do at least have very strong evidence that the market will fully solve this, and that we will as a country and a planet be able to afford it. I realise that this won't please those people who see it as a jigsaw puzzle, and who need to see the lid to get the full picture before starting to solve the puzzle. But radical transitions just aren't like that. Instead, we have an idea of many of the shapes in the picture, and many of the colours. But there isn't a single picture to aim for - there's a range of possible good-enough pictures, and we have the resources to make useful extra pieces as we go along. Some innovations we don't have time for - it's senseless to put things on hold until fusion or magically cheap small modular nukes appear - the time from early prototype to commercial-scale roll-out is too long. Other innovations are happening in good time - the huge cost reductions in offshore wind, in battery storage, in PV, in smart grids, electric vehicles, and so on, bears that out.

A zero-carbon target is important. Let's remember it's not the only challenge we've got. We are still resource-constrained, which means that we cannot ignore the economics. And right now, the economics favours early closure of nuclear plants. I agree with M that the cost savings are hidden, while the expenditure is not, and that that is a challenge for politicians. It does require politicians to be a lot franker with the public about the actual trade-offs. The challenge is that about half the public are insisting that they can have their cake and eat it, and they've been led to believe that by politicians who know full well that those sort of fairy stories end in bitter tears.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: pdf27 on June 15, 2018, 01:00:24 PM
I always struggle with the rationale behind the "social cost of nuclear" calculations, mostly because the statistical basis for them is extremely weak.
  • For radiation protection modelling, we use the linear no-threshold model: this assumes that cumulative radiation exposure is what matters, and that risk scales linearly with exposure - reduce the exposure by a factor of 10 and you also reduce the chance of cancer by the same factor. We have two good data points where people were exposed to known, high levels of radiation and tracked through their lives to give excess cancer rates - Hiroshima and Nagasaki. There is strong reason to suspect that this curve is not in fact linear but that high dose rates are much more damaging than low dose rates - but nobody really knows what shape this curve is: there are even still people who (rather implausibly IMHO)think that low dose rate radiation is actually protective against cancer.
  • A large fraction of the cost of an accident is related to how the cleanup is done, and that is largely a matter of what is acceptable to the public rather than being based on a measurable and acceptable level of risk. The Fukushima evacuation, for instance, almost certainly killed more people than it saved: the radiation levels across most of the zone are no worse than the naturally occurring levels in Cornwall, and we know that forcing elderly and vulnerable people to leave their homes will cause an increased rate of mortality. At the same time it would have been utterly acceptable to the Japanese public not to evacuate everybody in a zone where there was a measurable increase in the background radiation level, whether or not this would be good for them. The key point here is that the size of the cleanup/evacuation zone (and hence of the economic impact) will depend enormously on the public reaction to any accident - and this will be heavily influenced by both the prevailing culture in a country and the way the authorities handle the aftermath. The Japanese government and TEPCO both handled things poorly here, and due to the legacy of Hiroshima and Nagasaki I would expect the Japanese public to be more than usually sensitive to any release of nuclear material.
  • Location & weather conditions at the time of the accident are both hugely influential as well, for instance an accident at Bradwell when the wind is coming from the North-East would be very different to one where it is coming from the West. The only real way to approach this is to do a huge number of Monte Carlo simulations to predict the probability of each scenario, for each nuclear site and accident combination. That's a rather large task, so it would be very tempting just to take a particular site and study it alone, then extrapolate for other sites around the world.
The Leipzig study is at https://www.versicherungsforen.net/portal/media/forschung/studienundumfragen/versicherungsprmiefrkkw/20111006_NPP_Insurance_Study_Versicherungsforen.pdf - I'm struggling a bit with some of the terminology, but if I'm understanding it correctly the calculations were done based around the solvency requirements for insurance companies which require a 99.5% probability of making a profit where enormous risks are being insured.
The biggest variation seems to be how long after the premiums start to be paid that the insurance company must be able to pay out the loss insured for - compound interest has a massive effect, and all nuclear scenarios are extremely unlikely (1 accident per million years being a common standard to design to). If you want the insurers to be able to pay out after 10 years, the premium in the study was calculated at ~500 Billion Euros per year per power plant: however, from year 11 onwards the insurers have got sufficient money to cover any accident (indeed, because it is invested they are making a profit on it) and any further premiums are pure profit too. Because the study was limited to Germany, they seem not to have investigated the alternative way of lumping all the power plants worldwide into a single risk pot, which minimises the impact of compound interest and gives you a halfway decent chance of understanding what the social cost of nuclear power actually is, because as far as I can tell the 140-6730/MWh is the amount that a commercial insurer would have to charge to be able to assume full liability in a nuclear accident, which given the restrictions they operate under is not at all the same thing.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: knighty on June 15, 2018, 02:44:01 PM
As I've recently commented I understand the need for more interconnectors but have a different view when it might mean having one as little as 0.6km from our house!!!!!!!

why?

I don't understand the nimby mentality


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: M on June 15, 2018, 03:44:02 PM
A zero-carbon target is important. Let's remember it's not the only challenge we've got. We are still resource-constrained, which means that we cannot ignore the economics. And right now, the economics favours early closure of nuclear plants. I agree with M that the cost savings are hidden, while the expenditure is not, and that that is a challenge for politicians. It does require politicians to be a lot franker with the public about the actual trade-offs. The challenge is that about half the public are insisting that they can have their cake and eat it, and they've been led to believe that by politicians who know full well that those sort of fairy stories end in bitter tears.

As you say we don't yet know what to aim for, but here's some more good news that 60% leccy from RE (actually just wind and PV) is looking fine:

Solar and wind could provide 60% of UK power without jeopardising reliability, study finds (https://www.solarpowerportal.co.uk/news/solar_and_wind_could_provide_60_of_uk_power_without_jeopardising_reliabilit)

I'm sure I remember being told that 20% was an upper limit, then 30%, when we hit 20%, then 40%, 50% etc. The naysayer limit always seems to be just above where we are, whilst investigations seem to suggest ever higher potential.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: dimengineer on June 15, 2018, 08:30:34 PM
As I've recently commented I understand the need for more interconnectors but have a different view when it might mean having one as little as 0.6km from our house!!!!!!!

why?

I don't understand the nimby mentality

|There's Nimby and theres' Nimby. 600m is actually quite a way away. I have a tube line 600m away in suburbia - could be 100km. I never see it or hear it. But if it were just across the bucolic valley in full sight, I might think different


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: djs63 on June 15, 2018, 08:45:46 PM
Pdf27
I get your analysis with no buts or ifs. However, working with radioisotopes in a medical situation I used to believe that particles emitted might collide with a DNA or protein molecule and cause a change but given that there is lots of space between molecules the chances are small, but, the more particles emitted the greater the chance of a damaging collision. I thus tried to minimise exposure.

However, how you scale that hypothesis up to the world of nuclear reactors and drums of radioactive waste and thereby calculate the risk of damage to people and the environment is a mystery to me.

So
I would go back to the basic assumption that damage arises by chance collisions inside body cells and that more radiation means more risk.  And the energy in the particle....... linux:

Wind, PV and hydro sound good to me.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: pdf27 on June 15, 2018, 09:51:11 PM
Pdf27
I get your analysis with no buts or ifs. However, working with radioisotopes in a medical situation I used to believe that particles emitted might collide with a DNA or protein molecule and cause a change but given that there is lots of space between molecules the chances are small, but, the more particles emitted the greater the chance of a damaging collision. I thus tried to minimise exposure.
The ratio between exposure rate and a harmful mutation is the critical one, and while it is well understood at high dose rates the effect at low dose rates is not at all understood. There is some evidence that the body is able to repair damage below a certain rate pretty well - for example, smokers who are exposed to radon have a vastly higher rate of lung cancer than you would expect from evaluating the two effects individually. It's not perfect so all the radiation protection principles still apply (dose rate to be ALARP, etc.) but the distinction is pretty important when calculating population effects from a major accident.

However, how you scale that hypothesis up to the world of nuclear reactors and drums of radioactive waste and thereby calculate the risk of damage to people and the environment is a mystery to me.
They've taken the simplest of all possible models - worked out what the cancer rate is for say 500 mSv exposure in one hit, then said that 500 people getting a 1mSv dose or 1 person with a 500 mSv dose will have the same number of cancers as a result. Work out the population exposure from any hypothetical accident, and you get your cancer rate. Problem is, what limited evidence we have (it being massively unethical to do human studies!) suggest that this particular model (the "linear no threshold" or LNT model) really doesn't work at low dose rates. It's prudent to use it for radiation protection purposes because everybody is confident that low doses aren't more dangerous per mSv than high doses and so the public will be protected as a result, but it means the estimates are likely to be inaccurate.

Wind, PV and hydro sound good to me.
With appropriate regulation, yes - I get rather irked when some people seem to think that they're automatically safe. PV and Wind involve working at height which is inherently dangerous, and PV in particular is often installed in a domestic roof setting where installers may skimp on scaffolding, fall restraint, etc. to save money. Dams hold a huge amount of stored energy and need to be treated with particular care - the deadliest power generation related accident by some margin was the Banqiao dam collapse (https://en.wikipedia.org/wiki/Banqiao_Dam) which officially killed 26,000 people from flooding and 145,000 through subsequent epidemics and famine. They can all be done safely - but attention to detail and rigorous risk analysis is required to ensure that appropriate protection measures are in place. For what it's worth I would be keen for all three to be expanded as fast as practicable in the UK, but I'm not blind to the fact that they have flaws too.


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: brackwell on June 16, 2018, 09:19:16 AM
RE curtailment payments.

I am led to believe that this only applies to wind generators.  In both wind and FF generators get paid the grid price for the not produced leccy (also bearing in mind this could be a very small amount in times of oversupply) but only in the case of wind is there an extra curtailment payment.  This curtailment payment might have been justified in the early days of wind but not know?

Ken


Title: Re: Gridwatch Overnight Tonight 14/06/18
Post by: azps on June 25, 2018, 06:52:16 AM
RE curtailment payments.

I am led to believe that this only applies to wind generators.  In both wind and FF generators get paid the grid price for the not produced leccy (also bearing in mind this could be a very small amount in times of oversupply) but only in the case of wind is there an extra curtailment payment.  This curtailment payment might have been justified in the early days of wind but not know?

No, all technology types are able to bid into the balancing market to get those curtailment payments. Wind is not special at all in that regard. And how else can the system operator ensure that demand and supply match, and that no transmission links are overwhelmed, given the market structure? They buy regulation services. Anyone can sell them. It's just that wind happens to be particularly good at selling this one kind of regulation service: ramping down very quickly at very short notice.

Part of the problem has been that a lot of wind was built in Scotland, but there's not much consumption up there, meaning lots has to be moved South. And, due to one thing and another, building new north-south transmission capacity happened very slowly. So there used to be lots of times when there'd be too much power generated up North, and no way of moving enough of it down South, so there was a valuable market for ramping down generation in Scotland.

Now that the Western HVDC Link (http://www.westernhvdclink.co.uk/) is operating, the need for curtailment of Scottish wind is expected to drop a lot.