National Grid Share Discussion Threads

[deanforester] 19/11/2015 17:32

Pierre, combined cycle gas generation is actually more efficient than the best coal-fired generation and the capital cost is considerably lower. There is plenty of data about on the subject. Pollution control is also much simpler. No particulates, no SOX and a limited amount of NOX. Ignore the CO2 emissions, as they are a total red herring, but they are considerably lower than with coal firing.

[gbb483] 19/11/2015 12:14

*We've used wind for longer than we've used coal and gas.

and what did the miller do when the wind didn't blow? lost his trade to the water mills / tidal races.

[pierre oreilly] 19/11/2015 10:58

Wind can't be developed to be a reasonable generation technology for a power matching grid. It is intermittent, i.e. uncontrollable, therefore about as much use as an uncontrollable car, which goes where it wants when it wants and at what speed it wants. You can give the illusion of wind contribution at low levels of penetration, but it all breaks down (due to insufficient primary reserve, which corrects for the intermitency) once the level od intermttent penetration gets larger. As Germany and the uk is now discovering. Countires with high and successful penetration levels have a large supply of primary reserve in the form of hydro usually, but most countries don't have that.

[praipus] 19/11/2015 10:45

Hmm getting hung up on any finite commodity is risky isnt it?

Being able to use any source of energy just seems sensible.

Leading the world in to developing renewables would have been cool but seems UK gov screwed Nuclear, then renewable Wind*, Hydro and Solar and now coal!

We dont seem to have any problems promoting and supplying weapons technology.

*We've used wind for longer than we've used coal and gas.

[dr biotech] 19/11/2015 10:44

Hmmm. Amber Rudd is certainly getting into the media a lot.

[pierre oreilly] 19/11/2015 10:10

Yeah, and an expensive one by the time you've burnt t, driven a gas turbine and generated electricity, and then shipped it over a grid. It's fine imv for topping up the bulk supply furing higher demand periods, but madness for the bulk supply. Gas can be distributed to homes and burnt extremely efficiently in people's homes through existing infrastructure - madness using gas so inefficiently - the thought of me driving my nightime heating from electricity produced from gas is cringeworthy imv. Probably getting about 35/40% of the heat in my house, the rest lost elsewhere.

But when the choices for the next several years are limited, there aren't many options. Of course this will be costly and see bills rise a lot. There's also the issue of primary instantaneous reserve, currently from steam plant - not sure what they are planning there (if anything). GTs are fne foir secondary reserve in the minute timesframe, but no use afaik for primary resevre for response in seconds. My guess is that frequency support will come from remotely chopping the supply to those with smart meters once all other avenues have been exhausted.

The govs word were chosen carefully, saying things like 'old, inefficient coal stations' which are coming to the end of their design lives anyhow over the coming decade, so disigninuity there. I think coal from efficient and newer stations will stll be there in 10 years time, whatever is said today, but the old ones will be gone, just becaue they're at the end of their lives.

At least the plans for gas are reasonable under the circumstances of no choice for the medium term, and moving away from ridiculous wind and solar is to be commended.

[praipus] 19/11/2015 09:45

Is gas a fossil-fuel?

[tonio] 16/11/2015 12:15

Well, until/if we get local fracked gas and/or maybe good old coal to gas conversion brought up to date a la Algy Cluff, there is LNG by the gigantic shipload as an alternative to the Russian piped stuff (we imported 124 TWh's worth in 2014). If it's good enough for China who are importing it in enormous quantities it's ...
The cost of our electricity has been cheap because of coal and of course its direct conversion into electricity is the efficient route. More of that doesn't seem to be there as a realistic option presently and I wouldn't wish deep-mine working on anyone, so gas is the next best - if more expensive alternative.

[pierre oreilly] 16/11/2015 11:07

Maybe if we get a us-type supply of fracked gas it may be a sensible choice. We already have many small gas stations following the 'dash for gas' - the main advantage there was the relatively cheap and quick, but still very expensive, build cost. Not so cheap to run of course, in fact very expensive. Under the old scheduling system, where the price paid to everyone was the price of the most expensive station scheduled, prices went through the roof when gas turbines were used for the final few MW of the schedule (when for example a few coal or nuke stations were down for maintenance during a high demand period).

True value and costs were much easier to see in those days, before all manner of subsidies were introduced to vastly distort the underlying cost and favour 'renewables' to the extent of giving the grid the obligation to accept wind and solar under (almost) all circumstances.

The economics of gas I should imagine are much worse now, with capacity factors dropping due to wind priority (i.e. a new expensive gas station used more or less only during peak periods and when the wind isn't blowing at other times) would be expensive machinery doing nothing most of the time.

A further strategic disadvantage of gas is, until we get our own fracked gas if ever) means many countries between Russia and the uk can simply turn the supply off when they choose. So we don't want to be too reliant on gas.

[tonio] 16/11/2015 10:29

I've been a proponent of Nuclear Power all my working life but at best now it's a longish term solution and - as we've left it so late to make any move in that direction - we're lumbered with the prospect of paying through the nose for a reactor type that is unproven. All very sad really, but it is what it is.
Short and medium term gas-fired power stations seem the obvious if not the only way forward.

[pierre oreilly] 16/11/2015 10:18

While Ms Rudd has a refreshing view of the billions spent on renewables, I'm not sure she's grasped the scale of the upcoming problems.I don't think anyone at all relishes the thought of keeping old coal stations chugging on, and much worse extending the lives of aging nukes. That situation is not pleasant at all and could easily have been avoided. But we have run out of options and we shall be running nukes beyond their design lives. A stupid thing to do, but still not as stupid as not doing so, even with the increasing nuke risk.I expect ms Rudd does actually realise and she's putting on a political face.

[tonio] 16/11/2015 09:33

Not a great day to discuss energy needs. but a straw to grasp from:


'But Ms Rudd is also expected to make clear that eking out more power from Britain’s ageing and polluting coal-fired power stations is not the solution to keeping the lights on, and new gas and nuclear plants are needed instead.'

[prewar] 13/11/2015 13:14

Nice one Cyril!

[minerve] 13/11/2015 11:59

Well done Cyril!

[pierre oreilly] 13/11/2015 11:29

I would think Cyril Smith would be good for a couple of MWh.

let's work it out.

fat is about 37MJ/kg, so Cyril at est 160kg is 5920MJ which is 1.6MWh (not a bad initial guess!).

if it takes 0.25kWh to boil a kettle, then Cyril would boil it 6000 times.

[minerve] 13/11/2015 10:56

Yes, SNP too. Add in Merkel, she will keep a house warm for a week or so. :)

[gbb483] 13/11/2015 10:31

How much power can you generate from incinerating politicians and greens?

[kibes] 12/11/2015 15:17

onio - they are shortly going to have a climate change meeting in Paris at which all sorts of hysterically unachievable targets will no doubt be set. Anything to do with new coal/oil/gas generation is likely to be kicked into touch. We really are going to run out of power.

[skinny] 12/11/2015 12:50

National Grid is today hosting an event in London for investors and analysts to give them an opportunity to meet with the US leadership team and to hear an update on the activities of the US business.

Materials provided at today's event will be available on National Grid's investor website www.nationalgrid.com/investors and Investor Relations App after the event.

Webcast: For those of you not attending, a live webcast for the main plenary session beginning at 2pm will be available by registering at: - This link will also be available to replay after the event.

[tonio] 12/11/2015 11:57

Hmm, answer seems simple -so it probably isn't. Build gas-fired power stations, quick and cost-effective and according to BP there's loads of oil and gas around- wouldn't even need to frack.

[pierre oreilly] 12/11/2015 10:24

If you want a generator to boil a kettle, then you're looking at 3 grand - and you still won't have any lights unless you rewire your house specifically for a generator. It's certainly not simply a case of buying a generator and you're back to normal!. Even those of us with solar panels will get no power during a power cut, assuming the sun's out. No even sure whether most gas ch will work (we're all electric). Basically power cuts when they are likely (cold winter early evenings) mean most will go cold - which of course if often deadly for the frail.

As to Nukes - it's no surprise they take 10/12 years to build, so why are poeple surprised and criticise Nukes because those ordered today won't contribute anything for 10/12 years? 10 years ago, the whole of the uk was anti-nuke, even though the industry knew and communicated the upcoming lack of reliable capcity and the nuke lead time - but did many - or even anyone - listen? The greens did a very good hatchet job on nukes for the last 50 years, and it's likely virtually everyone believed in their views. It's only very recently there's been a more favourable viewing of nukes in general.

[kibes] 12/11/2015 09:14

The real government stupidity to me is shutting down old coal/oil/gas fired power stations with nothing to replace them. People talk glibly as if wind and solar power were the answer but on a cold still winter's night with peak demand the amount these are generating is a great big zero. More nuclear generation is certainly necessary but that is moving at a snail's pace. The supply/demand balance is currently far too tight and National Grid can only do the best it can to keep the lights on. If the power supply is not secure people will start buying their own standby generators which will completely defeat all the government's green targets.

[m100] 11/11/2015 16:27

"From the fact that last week we had the first near brown out across the whole of the UK"

Although it appeared widely across the media that's the tabloid headline and not really the truth.

There is no need to panic about the Notice of Insufficient Margin (NISM) last week, they have happened numerous times in the past, less so in recent years.

Page 14 of this pdf has the systems warnings issued between 2004 and 2007



It is quite normal for margins to be lower (than the 5.1% headline winter figure) outside the winter peak and the extra generation called for, 500MW was not a lot, about 1% of demand.






What if there’s a shortfall?

If a power station develops a fault and can’t generate electricity, or if there’s an unexpected spike in consumer demand, we use one of the following tools to communicate shortfalls to the market:

Notice of insufficient system margin (NISM) – this is a formal communication that lets market players know that our usual ‘safety cushion’ is not as big as we’d like it to be at a particular time of that day

High risk of demand reduction (HRDR) – we use this when we don’t have much time to notify the market of a sudden shortfall

Demand control imminent (DCI) – if the market doesn’t respond to the HRDR, we can issue a DCI notice asking the electricity distribution companies to reduce demand across their networks. Often a slight reduction in electricity voltage will do the trick – consumers may notice their lights dimming. But if there’s a very severe supply disruption, the distribution companies may need to implement controlled power cuts to homes and businesses.

[skinny] 11/11/2015 15:59

Worth a read -