Hitting 1.5  degrees is bad news, but not the end of the world. It’s not even the COP target; that is for global temperatures to exceed a 1.5 degree rise over a period of time, not just for a specific instance.

None of which in should in any way diminish our efforts to reduce emissions, of course.

 
In more good news, it appears that the proposed 1.5 degrees limit to global warming will be broken this year.
https://www.bbc.co.uk/news/articles/c1dpnxnvv2go

 

That didn't come as a shock. On the matter of China, time alone will tell, but they are building lots of new nuclear and renewables.

 
According to a recent U.N. report, the world is "wildly off track" regarding cutting carbon emissions.
Time for drastic actions to reduce fossil fuel use. Actual physical reductions, not trading or offsetting or exporting the fuel use.

https://www.bbc.co.uk/news/articles/ce8yyle2eq2o

 
I do not share the optimism expressed regarding chinese progress on climate change.
Here in the UK, coal burning has been drastically reduced for many years and has very recently been eliminated for grid electricity production.

In china they are still building new coal fired power stations on a large scale, and presumably expect to run them for the economic lifetime of 20+ years.
New coal mines are also being opened, presumably in the expectation that coal demand will justify continued operation for many years to come.

 

If she went to China, she would be surprised at the efforts they are making to cut emissions there. There are currently 22 nuclear power stations under construction, with another 70 planned, so she might be irrationally alarmed too. Pressurised water seems to be the favoured design, meaning higher "burn-up" of fuel. They are not the sort you would use to make weapons, unlike our own former Magnox fleet. On renewables, and Greta would surely approve, China aimed to have 1,200 GW installed capacity of wind and solar plant by 2030, but hit the target this summer, 6 years early. The momentum will continue, apparently more out of energy security fears than concern for the planet. They are worried they may run out of coal. Chinese use of coal has increased greatly over the past two decades because it uses an awful lot more electricity in total, but the proportion generated by renewables and nuclear is rising, and quickly. We use less electricity than we did in contrast. More efficient gadgetry is one reason, but we have also in effect exported a lot of the more polluting industries, importing the products those industries used to make from places like, er, China.

I'm no apologist for China's political class or system, but I reckon in 10 years' time, Britain will have made some modest advances in clean energy, if not actually achieving our stated targets, and China will be way ahead. This won't stop some people still citing Chinese fossil fuel use as an excuse to do nothing in Britain and the USA. It isn't just China: India is speeding up deployment of new renewables and nuclear power projects, and the UAE is moving from 100% gas-powered electricity plants to 100% renewable and nuclear.

 

From Global warming to Global Intifada it would seem....

https://x.com/RadioGenoa/status/1837601214135239055?t=nL96FiL_HutaSZP0RBDrNQ&s=19

 
In prison, possibly?  From Wikipedia:


 

 

All that's needed now is for China to follow suit, rather than commissioning tens of GW of new coal power every year, as well as thousands of coal mines, sadly our contribution is less than a drop in the (warming) ocean in this context.........where's Greta these days?

 

Hmm.  Germany ... hydrogen ... Hindenburg ...

Hasn't history taught them anything? 

 
In other news, forget about hydrogen powered trains. I have read a report from Germany, alas behind a paywall, saying in the bit that can be read for free:


...were delivered in time, and proved to be defective. Long story short, it seems that 12 trains were eventually delivered, out of 27 ordered, and they have not cut the mustard. Germany was the biggest cheerleader for hydrogen in Europe, but experience in real life hasn't matched the rhetoric, with the trains proving hard to keep running.

 

It's a landmark, and a welcome one at that. The next steps will need to be shutting down Drax, burner of foreign forests. That won't need any major legal stuff, just a simple non-renewal of the subsidies in 2027. After that, the government can start weaning us off gas for electricity generation. And once that's done, and the grid remodelled to replace life-expired kit and make it more suitable for the new ways of making and using electricity, we can move on to the 75% of UK energy use that isn't fuelled by electricity.

Closing the last coal plant is a big step that is worth celebrating, and which will earn a place in the history books, especially as it has such a definite date. RIP coal fired electricity generation in Britain, 12 January 1882 - 30 September 2024*. At the same time, though, it's a small step on the path to clean air and energy security.

(*Excluding electricity generated on steam locomotives etc. for the sake of of pedantry)

 
Good news.
Although to be pedantic, it is only GRID CONNECTED coal burning electric .power generation that has ceased.

Privately owned industrial power generating can continue, though I doubt that much, or indeed any, coal burning industrial plant remains these days.
A minute amount of electricity will still be produced from coal burning showmans engines at vintage fairgrounds and the like.
And of course we still have coal burning steam locomotives in use, the electric lights in the carriages, are indirectly coal powered.
Consider also electric lights on steamships and on steam road vehicles.

These are a minute load if compared to even a single coal burning power station, and retention is IMHO acceptable for heritage and historical reasons.

 
Not sure if there's a better thread for this, but power generation from coal in Britain stops today:

https://www.theguardian.com/business/2024/sep/30/end-of-an-era-as-britains-last-coal-fired-power-plant-shuts-down

 

On my first visit there, I was astonished to be told by a Welsh-speaking friend that Llantwit isn't the original Welsh name (Major obviously never was). That was Llanilltud Fawr, after St Illtud, founder of the 6th century monastery and college attended by St David. It's worth a train ride, and clearly also a walk.

 
As a brief aside. My railway based walk on Wednesday along the Wales Coast Path between the rather splendidly named Llantwit Major and Barry took me past Aberthaw power station.  With demolition due to begin this year, the landscape should look very different in the not to distant future, not least when the chimney structure no longer imposes itself on the surrounding scenery.
The plans for afterwards look interesting and if some of that land is added to the current adjacent biodiversity area it will be very tempting to do the walk again in a few years (legs permitting but I could always shorten the yomp to Rhoose Station).

 

Completely agree.  They cannot blame covid because they wotked through lockdown.

 

I suppose it won't be completely finished until Hinkley C starts pumping out electricity, but I gather some earlier lines have been replaced by the new stuff. The point I make though is that if it take 8 years to lay 57 km, how long will it take to do the rest of what is needed?

 

We live in the middle of this line and it all appears practically complete with cables up / underground and work has started returning the land to agriculture.  I would be surprised if it was not finished next year.

The cost comes directly or indirectly from your electricity bills.

 

It will be National Grid who will be salivating here. We have one project fairly close by to connect new clean energy to the grid, in the shape of the Hinkley Point C connection. This involves a new transmission line of 57 km in total. Work began in 2018 and is scheduled to be completed in 2026. I wonder how many years the new knitting will actually take, even with a few months knocked off the bureaucracy, and where the cash to build it all will come from?

 

Plans for grid upgrades are now published, so as to allow for  more renewable generation to be connected.
Let the nimbyfests commence !
https://www.bbc.co.uk/news/business-68601354

 

National planning policy used to have a presumption against development on the best agricultural land and I would support its reintroduction. However, much of the agricultural land in the West and Wales is not the best and so there are plenty of opportunities to develop solar on that land. 

Furthermore in other countries other forms of agriculture coexist with solar panels; it even has a name - agrivoltaics (see here for more information) and there seems to be no reason why we should not introduce this in the UK even on good agricultural land. In these systems the panels are on longer poles that allows agricultural machinery to work underneath. 

 
The space taken up by wind farms is in my view a non issue, most of the land between the turbines can still be used for farming, and the access roads built to access the wind turbines are also useful.

The space occupied by solar farms is of greater concern as agricultural use is considerably reduced. Sheep can graze between the racks of solar panels, and indeed sheep are almost a requirement  to keep vegetation under control as this would otherwise shade the modules.
Sheep like solar farms ! when the sun is too hot  or the winter snow/wind too cold  they can shelter under or behind the panels.

https://www.youtube.com/watch?v=7PXKnwvDnqwvideo about sheep grazing on a solar farm

 

Yet another good selling point! A small modular nuclear plant producing 300 MWe will need as little as 7 ha and some designs are cooled without lots of water. Hinkley C has a site covering 174 ha to produce 3.2 GW when finished, so it's big, but so is the output. There's an 18 MW wind farm a few miles up the road with an area of about 144 ha in total, and a 49.9 MW solar farm covers 61 ha, to put the land use into context. The latter two operate on a purely part-time basis.

 
Before any undue optimism breaks out regarding small modular reactors, do remember that "small" is a relative term when comparing them to existing designs.
The expected output is 500 MW or thereabouts. A 500 MW steam turbine and alternator is a very substantial piece of equipment. Consider also the step up transformer, switchgear, cooling tower, feed water pumps, condenser water pumps.

Smaller than Hinkley point, but still substantial.

 

They have actually been building one form of small nuclear reactor since 1966, to power nuclear submarines. These are smaller, but have the added complication of being carried around underwater in a confined steel tube, accompanied by 135 submariners, 16 space rockets, and up to 192 (usually 48) nuclear warheads.

Governments tend not to act unless and until they have to. Coal was fine for a long time. Our early Magnox nuclear power station were built to make plutonium for the bombs, with electricity as a good selling point and a means of getting rid of all the pesky heat. Gas and wind turbines were the order of the day in 2002, but coal and gas are now A Bad Thing, wind turbines don't work to demand, solar suffers from night time, and so suddenly nuclear is back in vogue with the two biggest parties. The question is no longer if, but how big. SMRs will appeal to the government of the day because they tick the green, sustainable and independent boxes with minimal fiction, and could be planned and delivered within the lifetime of a government. They'll be built in a factory in somewhere like Derby, then when the protests die down at the proposed sites, a lorry will pull up and a man in a cloth cap will ask "Where do you want this SMR?"

I know it won't be quite like that, but they could become commonplace fairly quickly, so paving the way for acceptance of new bigger plant as well. Among all the froth and bluster, it is easy to forget that civil nuclear power have provided us with very low carbon electricity for almost 68 years without harm to the population outside, and with fewer accidents resulting in harm to workers than in wind farms in the past 20 years.

 
Rolls-Royce, in association with various partners along the way, has been proposing small modular nuclear power stations since the late 1980s, largely to indifference from all governments, of whatever colour.

 
I would support the Rolls Royce small modular reactors, one of those would supply about 1% of UK peak demand, and a fleet of 25 would supply most of the non peak demand.

Not keen on chinese involvement for both quality control reasons and national security.

Not keen on hitachi either, if they cant build a decent train, who wants a nuke from them ?

 

When I was first looking to buy a PC many years ago, I realised the truth in that mantra. A friend fed me lots of doorstep-thick computing magazines, most of the content of which was 4-page adverts for computers featuring pictures of people dressed as Roman gods. I still don't know why, but I did spot that the prices went down and the specification up every month, meaning that I would have to jump on the roundabout one day in the knowledge that anything I ordered would be obsolete before it arrived.

Nuclear power stations aren't exactly like that, because there aren't as many small companies developing their own rapidly advancing technology. Changes in plans during construction cause delay and expense while sometimes adding nothing to the safety or efficiency to the plant, but in response to lobbying by laymen. Once built, the plants (or at least the nuclear parts) stay as they are as a rule, and I recall being surprised at how antiquated the instruments in the control room at Hinkley B looked. They were state of the art when building commenced, a bit dated when it began generation, and state of the ark by the time it closed, but they worked. EDF have said that construction of the second Hinkley C reactor is going much faster than the first because everyone now knows what to do, more parts are being engineered under factory conditions, and new techniques in putting it all together have evolved. The plan is to take that expertise to Sizewell and possibly elsewhere to build what will be in essence a copy of Hinkley C. The design has been approved by our nuclear watchdog after a few adaptations seen as over-zealous, but which may yet save our bacon - who knows?

China has taken this a bit further, with 22 nuclear power stations under construction and over 70 planned, now mainly standardised on their own Hualong 1 design. That design has been certified as compliant with both UK and EU standards. The ones already running took between 5 and 8 years to build and commission, probably helped by what I shall call charitably a simplified planning regime. Like Hinkley C, it is a pressurised water reactor design, aimed to maximise "burnup" of fuel. Unlike our earlier Magnox fleet, they are not designed to make bomb material.

It rather looks as though our new government will back small modular reactors. That is a step into the unknown to a degree, but I believe the Rolls Royce design recently submitted is a scaled-down pressurised water reactor. The plan is certainly to have them deployed quickly, with a construction time of 500 days, and start to finish build under 4 years. I shall watch developments with interest.

 
I can the see merits of nuclear power, but the delays and ever increasing costs are a significant concern.
Building more nuclear power stations to an already existing design should indeed be much cheaper and quicker, but would this be achieved ?
Or will each new plant have to be different include the latest advances and new safety features.

Remember the mantra of designers and consultants "if it works it is obsolete"

 
We missed a chance in 2001 to get nuclear moving again, but it's here again and should be taken. Part of the high cost of Hinkley C was the need to start from scratch again, training an army of people in the many skills needed to build a nuclear power station. The first reactor building for Hinkley C is nearly ready for the real guts of the job, the reactor core, to be installed. Building of the second unit is progressing more quickly than the first. Sizewell C is almost a copy of HPC, and should be even quicker when the workforce moves to there. Flamanville should have been the first, but will be the third, of the type to open. The reactor at Olkiluoto in Finland, also a European Pressurised Reactor, started commercial operations last April, but was beaten by the Taishan EPR in China. Solar and wind are obviously quicker to build, but with the disadvantage of being weather dependent as the snapshot from Gridwatch shows. The 2.1 GW of wind power is being produced by 28 GW of installed capacity. Solar looks good, although it's getting dark now. Demand is very low tonight, which is why nuclear is doing better than gas. Building more wind and solar will do us fine so long as we are prepared as a nation for long periods without enough power to go around or (more likely) keep plenty of gas plants in reserve.
Interconnectors are great for helping balance our grid. We can also export some of our pollution so long as the other side has spare power to send. Tonight's net 18% import of electricity, whilst still burning lots of gas to make electricity, doesn't look like what one could call sustainable throughout the year.

 
I am rather doubtful as to the deliverability of nuclear power. The French nuclear power station referred to above is many years behind schedule, and opportunities remain for yet more delays.
Hinckley point is also years behind and costs are still increasing.

Wind and solar power are available "off the shelf" for prompt installation.

International interconnectors are increasing in both numbers and capacity and can be most useful. We should however avoid becoming too reliant on importing electricity, the aim should be to be a net exporter of electricity.

 

And decarbonising what is not yet electric calls for superelectrification (or summat like that) - a slow process, as regards new nuclear generators and new transmission lines. So it's perhaps worth noting that the Flamanville EPR is in its final stages of commissioning (or "setting to work"). Grid connection is due this summer.

It was fuelled in May, and has done cold testing and is now doing hot testing. Despite what you might expect, no nuclei are harmed in this process - it's done by heating the water and running the pumps, pressurisers, etc. In fact, I think that big steam generators, not just nuclear ones, are heated externally before full power is unleashed. For one thing, it's very important that the turbine shaft and casing heat and cool at the same rate, as the running clearances are much smaller than the overall thermal expansion.

 
The UK continues to make good progress on decarbonisation of electricity generation, with coal burning almost eliminated and wind/solar increasing.
Progress on transport and domestic heating has been less impressive.

 
From the BBC:

https://www.bbc.co.uk/news/articles/ckkg0wl7dkro


BBC article continues.

 
I agree that the large scale burning of imported wood chips is not in fact green, despite claims to the contrary made by HMG. I am not opposed to the modest use of firewood for domestic heating provided that this is obtained from local sustainably managed woodlands, or from trees blown down in gales/removed for public safety reasons.

Wood chips imported  from thousands of miles away, by oil burning ships, are not green and I have little faith in claims made regarding sustainable management/replanting.

 

That went well for a number of years, although as we began to export our pollution, coal was shipped in from nearby Columbia via Royal Portbury Dock. Drax developed the idea, and now imports forests from Canada to burn here to make greed subsidies green power. Every little helps on the road to net zero.

 
I am very doubtful as to the merits of transporting charged batteries to near the place where electricity is required.

It would almost certainly make more sense to send the electricity via existing or newly built transmission lines than to transport batteries.
One of the original reasons for building the national grid was to facilitate the burning of coal in large, modern power stations near the coal mines, and to avoid transporting coal to distant power stations.

 
Now here's an idea that might be too American to work here. SunTrain propose to work with solar farm builders to site their generators where there's sun and not much else except a railway line. Then they charge a lot of batteries in a big (this is America!) train and trundle off to where there's a power utility short of generation and struggling to get permits for new power lines.

Neat, huh? But is it feasible at the right scale? For one thing you need a lot of big chargers, and for another you need a very big multi-battery inverter to get the energy out.

SunTrain talk about a 1 GWh train, which I reckon must contain about 10,000 tonnes of battery alone, plus the wagons and motive power. So Network Rail would probably ask you to split it into at least three trains for a start. Then you'd need the solar sites - no obvious local equivalent of Texas or Nevada (in terms of sun and planning) springs to mind.

But the tidal flood of solar panels heading our way from China over the next ten years is going to radically alter the economics of the energy business, even for those with modest amounts of sunshine, so things like this should continue to pop up as people think of them.

 

There is a limit to what pumped storage can do.  Batteries may be more useful in the longer term. 

However the best option is diversity. 
- Diversity in terms of different power sources - wind, solar tidal...
- Diversity geographically a large grid can balance generation geographically. Wind may be in the north of the GB on a particular day but not in the south. Solar may be good in one part of Europe but not in another on a particular day.  Even tidal has peaks and troughs in production, but a quick look at a set of tide tables will tell you that the troughs and peaks will be at different times around the GB. A grid can balance this out, the bigger the better. There are plans for an interconnector from N Africa to the UK to take advantage of solar power in the Sahara. 

 

As I predicted, so the Guardian produced on Thursday 21 December.



I'm not sure what the Guardian means by "generates 21.8 GW in half an hour", but it has never been my first option for science. There's a proverb that says something like "Good news arrives on horseback, bad news on foot", or if there isn't, there should be. You didn't see this sort of coverage at the beginning of the month, when wind power didn't get above 3 GW for three days.


How much more pumped storage is a moot point. Dinorwig will knock out 1.7 GW for about 6 hours. Coire Glas will add a bit more than that, but we get stalled high pressure systems with precious little wind every year that can last for days on end , including over a week last March, and nearly a fortnight in December 2022. Dinorwig, the existing other smaller pumped hydro plants and the putative Coire Gals would make little difference, representing as they do a mere fraction of the installed capacity of our wind fleet. Their biggest value is in reacting to short-term load variations to maintain frequency, like the million kettles after Eastenders. They do not regenerate during the day, so if used early remain empty. That role will continue when the country finally achieves an even load around the clock, but they are a form of back-up that still needs back-up. A true switch to net zero will entail doubling our electricity demand at the most conservative estimate, and we will need that load day and night, with more in winter. Pumped storage will help manage that, not provide backup at any meaningful level.

 
I still see a need for more new large pumped storage schemes, modern society needs power 24/7 and how to supply this without pumped storage is a challenge.
A lot can be done by shifting industrial loads and battery charging to times of plentiful supply, but there will still be a substantial demand for power on demand when there is very little wind. Pumped storage is very useful for this.

Pumped storage plant is also useful for black starting the grid after any emergency. Controls, instruments, emergency lighting and the power operated valves that admit water to the turbines all need electricity but this small demand can be supplied from batteries or from a small diesel engine.

At present most black start plant is gas turbines that start from batteries or air bottles, but with the rundown in fossil fuel plant this will not continue.
Interconnectors do not help with a black start, the inverters will not feed into a dead system.
Solar and wind power is generally connected via inverters that require an energised grid system, these also wont feed energy into a dead system.

 

That period covers the tenure of three first ministers of Scotland, all of whom seem to the sassenach in the street to have been trying to establish the country as a deep-fried banana republic, financed by the onshore wind industry. The middle of the three was the first to complain about the waste of excess electricity because of the inadequate connection to the south, and the last to try to do anything about it. Options including paying to upgrade the link or stopping building more were ignored in favour of complaining about the Westminster government not sending more money. For some reason, industry seemed reluctant to establish industries north of the border to use this bonanza, and I suspect this may be influencing thinking on Coire Glas.

SSE seems to be waiting for the UK government to stump up cash so that it can build something that will enable it to sell its own electricity to itself before waiting until the price is high, then selling it to the rest of us. But a few days ago, National Grid and Scottish Power announced contracts worth £1.8 billion to build a 2GW 525 kV HVDC link between Torness and County Durham, something that could see a significant reduction in excess power north of the border. At the same time, the growth of electric vehicles could introduce battery storage to households across the UK. Some models, including the Nissan Leaf but not, alas, mine, allow for bi-directional flow along the charging cable. Using the car battery to power the house when at home, then charging it cheaply after bedtime, could mean many of us evening out our own supply, with no need for another pumped storage facility. Maybe there was no hurry after all?

 

In the announcement of their own investment of £100M, SSE said:

Despite getting planning consent in 2010, the decision to go ahead is expected next year at the earliest. Good job there's no hurry, eh?

 
This evening is one of wind's better times, at almost 17 GW output, or about half of the installed capacity. Gas is down to about 2.5 GW and we're not actually burning coal. I strongly suspect that jubilant press releases will be popping up in editors' inboxes, and the hydrogen lobby will not be slow to join in - even though the figures could be reversed by the time the papers hit the street.

Spare wind power is capricious and the value of building infrastructure of any kind to use it is likely to be marginal at best. For the moment, the real slack times are overnight, so the price of electricity falls. When it gets down to 7.5p per kWh, my car starts to charge its battery, along with a small proportion of the nation's car fleet. As that proportion grows, more of that "spare" electricity will be used, making me wonder if whoever wants to build a new pumped storage has worked that into the equation. It isn't just private vehicles - First Bus in Bristol has a planning application in for expansion of the Hengrove depot, to include chargers for 130 buses. I make that about 19.5 MW when they are all plugged in. Imagine if 100 other depots in different areas of the country do the same, something almost certain to happen within a few years. Suddenly, two-thirds of a new nuclear power station is spoken for, and Coire Glas will be a very expensive muddy puddle unless it pays the same 7.5p. I suspect it will go ahead, even if it needs a lot of public money, because pumped storage is the closest thing we have to an instant injection of power.

Half of town gas was hydrogen, true, with carbon monoxide in more or less equal measure. It was thus very leaky and poisonous in more or less equal measure, and had less than half the calorific value of natural gas. Its manufacture was as a by-product of turning the coal we no longer mine into the coke for the steel we no longer produce at any scale, and gas works were easily found should you have cause to visit - "Just follow your nose, Sir". It is often cited in support of hydrogen as a boiler fuel, but we are well rid of it.

Without a doubt, the country needs rewiring, and there's another mammoth task. The Hinkley Point C Connection project, which has seen those cute T-pylons spring up across parts of Somerset, has taken 14 so far years from the first planning meeting, cost £900 million, and covers 57 km of cable. Actual building started in 2021, and has more than another year to go. We are going to need an awful lot more than that.

Gold hydrogen is indeed starting to excite people in the industry. Time will tell if it is achievable, or a chimera, but even then, the problems of storage and transport will prevail. My own thought is that industries such as ammonia and steel will spring up around any usable deposits, rather than having international transport of the gas.

Carbon dioxide from the distilling industries just goes to show what a damn fine drink gin really is - the answer to, and cause of, many of life's problems.

 
The promotional video, it's a bit snarky for my eye to be drawn to the caption 'A golden opportunity for a secret hidden power station buried under centuries' old rock', and yet it was. I'll try to be better. That aside, lovely pumped storage. Adventurous too in that Loch Lochy's part of the Caledonian Canal - the following touches on the implications.

https://static1.squarespace.com/static/60250f77169f1f1381bb3020/t/60a527ce775afc3733b87d73/1621436367353/vol_2_-_ch_6_-_water_management-1463264.pdf

It's curious to reflect that it's not so many years since this project would have involved building a rail connection to assist with the construction and also delivery of generating equipment. This aspect, back then, might even have given the line to Fort Augustus a day in the sun. Goodness knows such days were few. It would be interesting to find out if any components will be brought to site by canal.

The delivery of a transformer for one particular pumped storage installation in North Wales was recorded by British Transport Films.
https://www.youtube.com/watch?v=P4nqWE26yqk

On a presumably smaller scale and closer to coffeeshopland, Nailsworth was in receipt of something very heavy via rail - in connection with electricity distribution and perhaps whatever was delivered via the long vanished branch line is still in front line service.

Mark

 
As regards pumped storage, a new and very large pumped storage power station has recently been approved at Coire Glas

https://www.coireglas.com/

 
Proponents of a hydrogen economy point to the amount of renewable generation capacity that is not used at peak supply, but the biggest cause of this is the capacity of the grid to transmit it. At times of high winds, much of our wind generator capacity has to be turned off and replaced with gas generation simply because the grid elements connecting the wind power do not have the capacity!

Burning hydrogen to heat houses is not new - coal gas was IIRC around 50% hydrogen.  

As has been pointed out the process of converting electricity to hydrogen is very inefficient.  Anyone selling surplus electricity will almost certainly get a better price selling it to someone with batteries or pumped storage facilities!

Hydrogen as a fuel will IMO therefore have a very niche role as it will be expensive and requires a lot of storage space compared to methane.  

 
Tony makes a good point on the thermodynamic truth of green and blue hydrogen. I most cases, it is best just to use the electricity at the point of need or store that unused electric energy in a more energy efficient manner.

The beauty of gold or natural hydrogen is that the Earth has already expended its energy on creating it from its own nuclear energy reserves; crystallising the mineral olivine out of the Earth's mantle to make oceanic crust, or its equivalent. The Earth adds its own water (plenty of that about) to the mix and hydrogen is generated. Man's quest is to find where it has become trapped using his 100 years worth of oil and gas exploration techniques. That's a least what is keeping me, and several of my long-time colleagues, busy at the moment.

 
I very largely agree with the above, regarding hydrogen, with one exception. We do not need the carcon dioxide that is a by product of producing hydrogen from natural gas.
Until recently most UK carbon dioxide was produced by Distillers PLC, a company noted for the production of distilled spirits, this only ceased when carbon dioxide from natural gas was found to be a bit cheaper.

We could easily revert to carbon dioxide from the distiling industry (both potable spirits and industrial alcohol)

Carbon dioxide from natural gas adds to global warming.
Carbon dioxide from the distiling inudustry is green because it is only returning to the atmosphere that carbon captured by growth of the barley or other plant matter that is fermented.
If the barley was not used thus it would rot, be eaten by wildlife, or destroyed by fire and the carbon still returned to the atmosphere.

 
I think we are going to have to rename our lightest element as Hype-o-gen, given all the lobbying going on. A lot of money is being spent on extolling the virtues of multi-megawatt electrolysers to people who have no idea what one of them is, presumably in the hope that a picture of Rachel Riley will have us all writing to our MP demanding one on every street corner.  Yes, green hydrogen will be of use to industry as a replacement for the much cheaper (but still not cheap any more) current supplies obtained by steam reforming of methane, but it will come at a cost. The very idea of using precious hydrogen to heat homes is ridiculous, unless you own a gas pipe network. Then, it becomes a last gasp attempt to find a purpose for your £20 billion pipeline asset, which without gas running through it will be worth slightly below zero pounds. Hence why the biggest proponent of the abandoned Redcar experiment was Northern Gas Networks, and the only one of the many scientific reports on the subject to find that hydrogen would be good in household boilers was sponsored by Cadent.  The most efficient way to use hydrogen in home heating would be to power a heat pump via a fuel cell, which would be nonsensical given that you could just use the electricity expended on making the hydrogen instead, and save all the losses.

Hydrogen as a home energy source is an expensive way of turning a lot of energy into a lot less energy. That becomes more farcical when the electricity used to make the hydrogen comes from burning gas, whether it is done directly, or indirectly by using wind energy that could have supplied the grid. We are nowhere near the point where all of our daily electricity is made by clean means, and that is without the extra that will be needed to power 30 million vehicles, 60% of the railway, and the replacement of 25 million gas boilers. Our very rough average of 30 GW demand is going to be closer to 100 GW when (if) we ever get close to net zero, and there won't be much by way of off-peak electricity when the nights are given over to heating water cylinders and charging vehicles.

Ammonia production uses lots and lots of hydrogen, and the CO2 currently made as a by-product has a substantial market, although almost all of it ends up in the atmosphere in the end. You may recall that the increased price of gas almost did for our domestic NH₃/CO₂ industry, with government having to throw money at it, so what the change to green hydrogen will do is anyone's guess. Most of the hydrogen made in this country doesn't leave the compound where it is made, but goes straight into the next step of the manufacturing process. This avoids the need for transport over any distance, and thus the need for extreme cooling or extreme pressurisation. Gas pipe networks are going to need a lot of work to carry hydrogen safely in such volumes as will be needed to match methane. If I lived in an area where the experiment was to take place, I would opt for a heat pump. I have looked into it already, but our boiler is only 5 years old, and I don't like the idea of scrapping something that good.

"The government therefore still plans to take a decision in 2026 on whether, and if so how, hydrogen will contribute to heating decarbonisation." That won't be this current government. The other likely contenders seem to have a feel for hydrogen too, although not so passionately so. One day, we are going to have to ask people who did the same physics and chemistry O-levels as me, but took the education further than I did, to explain to our politicians in words of one or two syllables exactly what those pesky laws of physics say about all this. For me, it's a dead duck, but still quacking loudly.

 
Use of hydrogen for domestic and similar heating and cooking is rather pointless under PRESENT circumstances for reasons already given.
No harm though in tests, trials, and experiments in case this changes.

A large potential use for green hydrogen is the manufacture of ammonia fertiliser, this uses a great deal of hydrogen, almost always obtained from natural gas. The present high price of natural gas has resulted in fertiliser shortages and substantial price increases, and also in carbon dioxide shortages as this is a by product of producing hydrogen from natural gas.
Green hydrogen could be used instead, the fertiliser production process is well understood and does not "know" if the hydrogen feedstock is from natural gas or from electrolysis of water.
A possible interim step would be to use green hydrogen produced renewably when available, and natural gas derived hydrogen at other times. The eventual aim being to move to 100% green hydrogen.

The only drawback of green hydrogen for fertiliser manufacture is that no carbon dioxide is produced as a by product. There are other economical sources of carbon dioxide, which is much used in the food and beverage industries

 
With whatever is the opposite of a big burst of publicity, DESNZ sneaked out the announcement of what looks like a the knock-on effect of HAR1. One of the bidders that was not selected was HyGreen Teesside (BP Alternative Energy Investments), and though EDF's Tees Green Hydrogen was selected it is much smaller. Both are part of the Teesside cluster of hydrogen projects, lined up (without naming names) to supply the trial in Redcar of hydrogen piped to houses for heating (aka Redcar Hydrogen Village).

So that's been cancelled, not by an announcement as such but by editing a short update into the page hosting a document naming the winners of the bidding to do that trial (Stage 2):

DESNZ are still making positive noises about adding up to 20% hydrogen to gas supplies, of which trials are already underway.

 
Under PRESENT circumstances, hydrogen is rather pointless.
A great deal of electricity is used to make hydrogen, and it would in most circumstances make more sense  to feed this electricity into the grid, and thereby displace some of the natural gas otherwise burnt for electricity production.
Natural gas is still burnt 24/7 for electricity production.

However the position may change in future, and any future surplus of renewably generated electricity could usefully be used for hydrogen production.
Better get building a lot more wind turbines, and installing a lot more PV modules.

A new and very large pumped storage power station has recently been approved, and if actually built will reduce the need for hydrogen production, since surplus electricity can be stored in this power station.

 
A big burst of publicity from the Department for Energy Security and Net Zero (at least, big for a department no-one has heard of) about HAR1 - the first Hydrogen Allocation Round. Behind it is a small nugget of fact, that £400M will be invested by eleven successful bidders so they can start making green hydrogen.

Project Name	Lead Developer	Location	Capacity (MW)
Barrow Green Hydrogen	Carlton Power	North West	21
Bradford Low Carbon Hydrogen	Hygen	Yorkshire	24.5
Cromarty Hydrogen	Scottish Power and Storegga	Scotland	10.6
Green Hydrogen 3	HYRO	South East	10.6
HyBont	Marubeni Europower	Wales	5.2
HyMarnham	JG Pears and GeoPura	East Midlands	9.3
Langage Green Hydrogen	Carlton Power	South West	7
Tees Green Hydrogen	EDF Renewables Hydrogen	North East	5.2
Trafford Green Hydrogen	Carlton Power	North West	10.5
West Wales Hydrogen	H2 Energy and Trafigura	Wales	14.2
Whitelee Green Hydrogen	Scottish Power	Scotland	7.1

That adds up to 125 MW.  There's a rather woolly target of 10 GW by 2030, and HMG says, oxymoronically, "We remain committed to our ambition of having up to 1GW of electrolytic hydrogen in construction or operation by the end of 2025". So there's a next round underway - HAR2, believe it or not -  rated (prospectively) at 875MW.

So whose money is this? The government support is revenue support - a guaranteed price. The strike prices varies per project, and averages £241/MWh. Of course that relates only to use as a fuel; one hopes they will find some customers to exploit hydrogen as a chemical feedstock (e.g. iron refining).

 
Here's a thing - a rather silly looking thing too. From Business Live:

On second thoughts, if you stop thinking of this as a long-term solution to anything, it does perhaps have a place. It allows a strict net emission limit to be imposed early, but for some big emitters to keep going where they are for (say) ten years - at a significant cost, though less than building CO₂ pipelines. Or, put another way, if the government is determined to spend money exploring all the carbon capture options to see what they do, why not grab some for railways?

 
Presuming that this new pumped storage scheme goes ahead, I hope that rail transport is used so far as possible.
The site is not rail served, but a project of this size could justify the building of a new line direct to the work site and connected into the existing network at a suitable point.
A local passenger service to transport the workforce would be far preferable to use of cars.
A great deal of tunneling will be required, and the resulting spoil should be removed by rail. Granite has many uses including railway track ballast, making of concrete, and large boulders for sea defences.
And of course materials will need delivering.
Explosives will be needed, and are best moved by train.
After the works are completed, any new rail lines could be retained as a tourist attraction, or dismantled.

 
There's a good interpretation centre at Cruachan I would highly recommend if you are in the area. I recall that the display and film showed a lack of high vis, hard hats etc. during construction, and indicated that working conditions were tough, albeit that pay rates reflected them.

Not something that would be tolerated now.

 

Cruachen pumped storage power station was built between 1959 and 1965.  I can assure you that construction industry safety has moved beyond all recognition since then.  I started in the industry in the 1970's and the change since then has been massive and I know ot had already improved tremendously before then. 

 
Presuming that this proposed pumped storage scheme goes ahead, I hope the safety standards will be higher than in the past.

During the building of Cruachen pumped storage power station, many lives were lost. At least 15 men died, and some reports say as many as 36 lives were lost. Standards were lower decades ago, but the building of Cruachen is not exactly ancient history, it was during my lifetime.

Cruachen remains in use today, with largely the original equipment, and is being expanded.

 
Approval has just been given for the building of a new and very large pumped storage power station in Scotland.
Output of 1.5 GW and a storage capacity of 30 GW. That should save significant natural gas.

AT PRESENT we seldom have a surplus of wind power available to fill this new storage, that however will change as more wind turbines are built .
By the time that this pumped storage capacity is built, a night time surplus of wind power is possible in Autumn and Winter, and maybe a daytime surplus of solar energy in Summer.

Building this plant is a large civil engineering job, but the technology is well understood.

https://utilityweek.co.uk/inside-1bn-pumped-hydro-plans-to-more-than-double-britains-electricity-storage/

 
The proposal for green steel production sounds most interesting, but I a bit doubtful about anything so complex that also needs further research.

 

There are two diagrams in the paper linked to above, one for energy flows and this one for mass flows:


It's hard to follow, in part because of all the initialisms, and also the units are a jumble of kg, m³, and moles (gmol). But I think the carbon all goes round in the cycle, and none gets rejected to outside. Mind you, nitrogen isn't shown being rejected - and it must be or the whole thing would explode. Too good to be true? Probably, but hard to see why from a non-expert viewpoint.

I mentioned the gas separators, as the only methods I've come across are dissolving in a liquid (for CO₂ in particular) and successive liquefaction. Here, something splits CO, CO₂, and H₂+N₂ at above 700^oC - so what is it? Does it involve huge heating and cooling energy flows? I did spot this in the text, under "further research is needed":

 
Nice. But doesn't the resulting CO, when fed back through the system and either burnt or oxidised by iron oxides, produce CO₂ again? Sounds fine in theory, but will also need a lot of energy. Maybe a small modular reactor next to the steel works could save the day?

 
You may recall the Swedes were getting on with the challenge of replacing coke in steelworks by hydrogen. Hydrogen has its issues, even for those who do have Swedish hydroelectricity to hand. Now someone has popped up with an alternative, based on a bit of molecular sociology to persuade CO2 to give up its evil ways and become CO instead. This is from Yahoo Finance:

It's only a paper study so far (see paper in the Journal of Cleaner Production), and some of the blocks in the diagram look a bit tricky - like the ones labelled "gas separator". But it must be worth a punt of someone's money, as the potential pay-off is big enough to override the low probability of it working well straight off.

In January the government offered the British steel industry £600M, as a combined rescue and "encouragement" to get greener. As a home-grown idea, it's tempting to think this would fit in with that project. Sadly, I doubt the industry will last that long.

 

I'm with broadgage in terms of scepticism, but I'll try to watch at least some online if there is a timetable. I'm keen to know if this free hydrogen is concentrated and attainable, or plentiful, powerful but spread out, like wave power.

 
I doubt that I can get to the conference, but would be most interested to hear reports, via this forum or otherwise.
At present I still consider the whole idea to be very improbable, However my mind is not closed to new developments and I find this an interesting possibility.

 

It might put you in your discomfort zone but natural hydrogen generation is around us, and has been understood as a geological process for a long time.

Come to our conference in July to hear several dozen respected geoscientists deliver their papers to a hundred or so of their peers; I'll buy you a port.

Natural Hydrogen: A New Frontier for Energy Geoscience.

Oxonhutch FGS

 

I believe that your assumptions were correct.
Few natural processes produce free hydrogen, and the alleged discovery of useful volumes of free hydrogen sound very improbable indeed.

 

Depends on how much there is in the area when the match is struck.

 

Methane (and petroleum ['rock oil']) is derived primarily from high organic rich shales heated to between 90 to 120 deg Celsius through natural burial (known in the industry as the 'oil window' - gas will be produced at a slightly higher temperature). It is estimated that 98% of all hydrocarbons that are/have been produced are lost to nature where they form very rich feedstock for other creatures. Hydrogen is the same - an energy rich feedstock.

The chairman of BP got into trouble after the Deepwater Horizon disaster by saying it isn't as bad ecologically as it is made out to be. His reading of the room was entirely wrong and deemed to be highly insensitive under the circumstances - and I whole heartedly agree, but as a geologist he was geologically correct. The sea bed of the Gulf of Mexico is constantly bleeding oil and gas that is being produced as we speak by entirely natural processes. There is a huge natural biota that feeds off this output and consumes it with great efficiency.

Gold hydrogen has nothing to do with the chap you mention, it was chosen by the industry as it has to be mined from the ground like the precious metal.  Also referred to as 'white' because it is so naturally clean compared to the other different shades of hydrogen - some of which are decidedly dodgy!

 
And now the New York Times.

It's all getting a bit main stream 

 

You can have a huge amount of a gas percolating up through the ground and still not notice because its density is so low ('cos the world's a bit big). It needs to be trapped by an impermeable cap before it builds up to noticeable (or exploitable) quantities.

That's not just true of hydrogen - methane does the same thing. I think (but I don't think I've seen it said) that the overwhelming majority of the natural gas produced in the past vented to the atmosphere ages ago. Of course hydrogen does have a different idea of what "impermeable" means from other gases.

That idea - of methane continuously rising through the ground almost everywhere - I had filed away as one of Tommy Gold's theories, though that is probably only half true. But I did assume that this subterranean hydrogen was called "gold hydrogen" after him. But it seems not, officially. So it must be either pure coincidence, or a kind of in joke or punning reference.

 

I don't think you missed anything, it's just that any free hydrogen is either going to be trapped or is just passing through. It's certainly possible to envisage a boom in the future.

Mark

 
The irony is at the end of the article, where the village now has a ready, free, source of hydrogen, and a fuel cell, but still no electricity. Let's hope it's not predictive...

 
I have lived for decades under the assumption that there is practically no free hydrogen on planet Earth, and yet here it is, practically gushing out of holes in the ground in unimaginable quantities. Did I miss something, or did we all miss something?

 

One of our Natural Hydrogen Study Group members is featured in that article, and we have a conference organised on that very subject at the Geological Society, London this coming July.

 
...The word is spreading! From a long article in Science:

 
Very good analogy. 

 

I blame John Redwood. He is a member of "Leave Means Leave". It looks like the motor industry is doing just that. He is also wrong about the move to electric cars being the cause of the big damage. That is like saying the move to colour TV damaged the black and white telly industry. Moving away from fossil fuelled cars is inevitable, so if it is doing big damage, it's because of an inability to adapt - or a handy smokescreen. The car companies are moving because we aren't an attractive place to build cars any more, especially not for export. Such raw materials as are available have to be competed for these days, with the finished product subject to the sort of taxation we didn't need to think about between 1973 and 2020.

 

How about the failure of the government to get a good trade agreement with the EU and the failure of the government to provide support to a UK battery factory at the time it was needed is doing big damage to the UK car industry. It will get worse if the UK slashes all EU legislation in its proposed deregulation cull. 

 
From John Redwood on Twitter:


Any thoughts?

 

As I read this, wind is producing 1.85 GW. I wouldn't call that disappointing. There are other words that would fit better.

 
Only a few years ago, 5 to 10 GW from wind power was regarded as very impressive, yet now it is considered disappointing.
Shows the progress that has been made in recent years.

Every GWH of electricity produced from wind is several GWH of very expensive natural gas not burnt, but remaining in storage for later needs.
Gas supplies are at the mercy of foreign powers, wind power is not.

 

Well, that didn't last long. A few headlines and an entry in the Guinness Book of Records, and normal service has been resumed. Back below 10 GW at 3pm on 3 February, and not above since, save for a few minutes overnight. Solar had a few decent enough hours, but nothing to write home about. Gas has risen to cover. We need to find a better way.

 

The attrition rate for wind farm machinery is quite high, and many are already more than a decade into their putative 25-years tenure. There could reasons of finance or politics that get in the way of refurbishing them, hence my comment.

 An independent Scotland would doubtless love to trade electricity with England, the questions being whether it would be worth spending the necessary billions providing the infrastructure to transfer unpredictable  intermittent energy down from Scotland, and oooo's gonna pay for it. The English might think it a better bet to build more nuclear, small modular on the sites of decommissioned coal and gas plants, large by the existing estates to combine dismantling the old Magnox with operating new generation kit, and restringing the already antique grid south of the border. The Scots could then concentrate on showing us how it should be done, banning all fossil fuel vehicles (road and rail), closing all fossil fuel plants, keeping everyone warm with stored heat, and becoming very wealthy as a result on the basis of their burgeoning export of manufactured goods. And ferries.


Saddam Hussein polled over 98% of the votes in the last election before his loving population hanged him. On a more serious note, the Scottish government  consists mainly of a party that also serves as a campaign group, and a home for anyone who doesn't like Westminster being in charge. It will be interesting to see how things will change should the possibility of a binding independence referendum ever arise, and more so when the Scottish government has to suddenly become a full government, with the primary object having been met. The same applies to Aberthaw and all that surrounds it.



A good way to close. 


Welcome back, broadgage! Yes, I see wind has, like both of us, returned after a couple of weeks' absence.   

 
Good to see you back broadgage

 
On a more positive note, electricity from wind power recently reached 16.5 GW, another new record.
For the last 24 hours, wind power has been producing 15 GW which may be a new 24 hour record.
Wind power is now cheaper than nuclear and a lot cheaper than gas.

Wind power also the great advantage of being produced within our own borders without reliance on foreign powers.

For the foreseeable future we will still need some natural gas for electricity production in calm weather, so wind is not the complete answer. The present high gas price does underline the importance of maximising wind power and reducing gas use.

 

Or perhaps they care more about saving the planet for our great grandchildren than the loss of a view that was created by man's destruction of nature over the last 1000 years or so (depending on where you are talking about).

As for one party states at least the Edinburgh government was elected by about 50% of the electorate and needs the support of anotehr party to rule. The party that has ruled the UK for the that was elected by a 43% of those who voted and has a massive majority!  It seems to like running roughshod over the opinions of voters on many other things including onshore wind power.   

I don't see




We do need to build renewable energy across the whole country as that give the best diversity - it is less likely that there will be no wind or sun across the whole country than in one place.  Even better across a continent like Europe (if I am allowed to use that word). Trading renewable energy make good scientific sense. 

I cannot see why windfarms might not exists in a decade or so, or why even an independent Scotland would not want to trade electricity with England.  We still manage to trade electricity with the Europe with a Westminster government that seems hell bent on extinguishing all trade with the EU.  Fure renewable energy is likely to come from the far north of Scotland from tidal energy - the tidal flows at Scapa are a predictable stable renewable resource that is just right for harvesting!


The alternative solution to storing electricity is thermal heat stores.  These are more efficient than batteries - where the user wants heat (rather than electricity).   
https://www.youtube.com/watch?v=B3JlTVt0jLw


Agree

Edit - fix quote markup - Red Squirrel

 

Point of order: The UK did not generate 30% of its energy from renewables. It may have generated 30% of its electricity from renewables, depending on who is counting and what they are counting.

A quick look at the Digest of UK Energy  Statistics (DUKES) for 2021, the last year available, shows that renewables generated 122.2 TWh, down over 9% on the previous year. Wind production was down 14% on the previous year to 64.7 TWh because of the wrong type of wind (not enough). Solar was 6.2 TWh less whatever was generated by wave energy, looking at the electricity flow chart. That 122.2 TWh must therefore include over 50 TWh generated by burning stuff, 15 TWh being from Drax's burning of imported forests. That is only renewable if you are desperate to hit targets.

Digging further into the statistics, we find that total energy use in the UK was around 176,000 million tonnes of oil equivalent, or a little over 2000 TWh. Renewables actually provided about 6% of the UK's energy. This isn't just pedantry - we have been having the wrong conversation about the country's energy needs for a long time, and should be looking to the bigger picture if we are ever going to get away from fossil fuels.

On the matter of electricity, the author recognises that most windfarms are in Scotland because:

He has not done his research correctly. Onshore windfarms are no less unpopular in rural Scotland than in rural England or Wales. They just have a government that cares even less about the countryside than the English equivalent. He should have said that the government up there finds it easier to ride roughshod over local democracy than the Westminster parliament. This is helped by having a virtual single-party state (like China and North Korea), a populace concentrated in a few big towns and cities, and a close relationship between government and foreign wind companies. He points out the problems with moving electricity from north to south, which have been ignored by the Edinburgh parliament, then picks the one day of the year when industry is almost entirely closed to illustrate the problem. His solution is a cable costing £3.4 billion to connect windfarms that might not exist within a decade in a country that might not be trading with the rest of the UK in less than that to England which imports more electricity from other countries than it does from Scotland. A lot of the wind farms producing this occasional excess are in places that are vast distances from Edinburgh, let alone London. He does at least recognise the potential problems behind the idea of storing the excess, the main one that he only indirectly alludes to being that the batteries will most likely be used to store energy until the price is highest, rather than to help even out the flow.

He tells us that:

I have a workable solution to this problem, which is to stop building wind farms in Scotland until a use for all the power is demonstrated. Nobody seems in much of a hurry to invest up there, other than the foreign energy companies, so my idea would help spur them into thinking of a use for their product. There is plenty of scope, with the decarbonisation menu supposedly high in the minds of the Scottish people. Start ripping out gas boilers and putting in electric heating. Ban all new fossil fuel cars next year rather than waiting to 2030 (ha!). Make some of the fabled green hydrogen on the blustery days, or if you think you can transport it and sell it, make it all the time except when there's no energy at all to spare.

Another way forward would be to stop constraint payments altogether for new contracts. My local brewery doesn't demand constraint payments from me because I'm not drinking all the beer they produce.

I agree that the energy structure is not working as it should. Incentives are driving perverse behaviour, as they do in all of public life. We should be putting a lot more energy (NPI) and money into building clean reliable power generation than isn't so dependent on the weather, not spaffing a few billion on what will be fractions of a percentage point.

 

If you're interested in this kind of thing, here's the full post by Archy de Berker

https://archy.deberker.com/the-uk-is-wasting-a-lot-of-wind-power/

 

So in bright sunshine, you will be able to switch all the lights on for free. Next thing to sell you is a battery pack and another inverter, so you can save a few pence on lighting at night.

 
PV modules can be installed on gable end walls and useful power produced thus. A South facing wall will produce more power than a roof in UK winter conditions, but total annual output from a wall is less than from a roof. If the demand is primarily for lighting, than a south facing wall can be a good choice.

PV modules do not cope well with partial shading and damage may result.

If the whole module is shaded then they work fine but at a much reduced output. Bright but cloudy weather may give 50% output, heavy overcast only a few percent.

 

I was wondering this summer whether it would make sense to put PV panels on a gable wall. It needs something to keep the sun off, since the long period of heating during the afternoon and evening drives a lot of heat into the wall. A PV panel could power a heat pump (aircon) to remove the heat that still gets in e.g. via the windows.

The problem is that much of the gable is shaded part of the time. I don't think standard PV panels can cope with shading, since the cells are in long series strings. The electronics couldn't cope with a variable number of cells being lit per string. But I may inquire, just to find out.

 
It will soon be worthwhile installing PV modules on East or West facing rooves. The output will be much reduced if compared to South facing, but still worthwhile if grid electricity remains expensive and if PV modules get cheaper.

 

The array faces due south pretty much exactly, at an angle that seems to get all-day sky. There is nothing else in the way. We have a lot of sky, and it is easy to see the effect of the Earth's tilt through the seasons. Short of a motorised mount, I can't think how it could be done any better.

It would be interesting to know actual output at midday, but I don't have the facilities. That wasn't what I wanted to measure - I know that at certain times, I will be getting the full 1.2 KW, at other times nothing, and all points in between. I was interested in the bigger picture over a period of time. You only hear about renewables on good days as a rule - when the wind picks up and the garden furniture starts to lift off, I know that the papers will have banner headlines two days later about how wind turbines produced record amounts of electricity, and why the government should scrap all planning limitations for them, and send billions to the foreign owners to build more. The advocates fall silent when it's below freezing and we don't have a breath of wind for a week.


On this occasion and this specific subject only, I shall say that the actual size is of no importance. The roof there is the width of the house rather than length, so what I have there is pretty much all there is room for. The biggest unbroken piece of roof faces due east. It's at the back of the house, so would not spoil the look, but the isn't the optimum place, and thus not an economic proposition. As I explained above, it was installed as a ruse, almost, to get ticks in the correct boxes.

 
Grid tied PV is increasingly attractive when considering the increased price of electricity.
It is more economic if some of your electricity use can be shifted to the hours of sunlight. A 1.2 kw system is useful, but current thinking is towards installing nearly 4 kw.

Off grid PV, whether on a camper van or for isolated premises is also attractive since it is often displacing very expensive electricity from a vehicle engine or from a small generator.
There is no limit on the capacity of such systems. Even 50 watts helps a bit, and a few kw is ample for most households.

 
I have looked at the power generation of the 150W solar panels on my camper van.  I only get the nominal output when the sky is clear and the sun is at exactly 90degrees to the panels.  Either of these cause the output to rapidly fall off.  Therefore TonyK's 85% reduction from nominal is due to cloudy skies and non optimal orientation of the panel as the sun moves round.

It would be interesting to compare the output at 12 noon (if the panel points South) on sunny and cloudy days and at different times of day when the horizontal angle will be different.  The vertical angle will also differ between winter and summer.

 
I have just realised that for the past 4½ years, I have been running a non-scientific experiment without my own knowledge, to measure the effectiveness of solar energy. I didn't leap from the bath naked shouting "Eureka", just finished entering the meter reading for the feed-in tariff (FIT) for my small solar array into the website for the free money, and thought "Hang on a minute..."

The builder of my house added a 1.2 KW, nominally 1 KW, solar panel on an unobtrusive south-facing bit of roof. He told me this was not because of his green credentials, but the cheapest way of obtaining the coveted A rating for the Energy Performance Certificate. He had already done most of the other obvious things of insulation, underfloor heating, windows to minimise loss and maximise solar gain, and other methods like ground source heating would have cost a lot more. I paid little attention to it at first, but realised from the smart meter that there are long periods of sunny days when appliances were running without me using any of British Gas's electricity. I was pleasantly surprised by my first FIT payment - far from enough for another exotic holiday, but enough to cover dinner out, all without me doing anything.

I had long wondered how accurate were the claims made by developers of solar farms in their promotional material, concerning the actual output and the number of homes that would feed. After all, it does get dark a lot, although I am assured by someone who advocates covering the countryside with Chinese panels that they work on average 50% of the time across a whole year. Yesterday, it suddenly dawned on me that I had the means to estimate the effectiveness of solar power at my very fingertips.

I moved here at the end of April 2018, 4½ years ago, almost to the day. The meter for the panel records KWh produced by my 1.2 KW panel. I seem to recall it already had 50 or so on the clock when we moved in, but for ease of comparison, I will ignore that and assume a zero start 4½ years ago, along with a few other roundings of figures. The week contains 168 hours, 52 of those giving us a nominal year of 8,736 years. 4½ of those amounts to 39,312 hours of residence below my own personal little power station. Were it to have operated around the clock at the nominal rating, it would have produced 39,312 KWh of electricity. In fact, it has turned out 5,831.16 KWh. I make that just under 15% of its round-the-clock potential. A fortiori, if it is light 50% of the time on average, it produces only 30% of what my environmentalist mate thinks it should. I shall rub his nose in it when I next see him and refer to him henceforth as the environ-mentalist. I shan't be getting rid obviously - every little helps, it was here when I bought the place, and rooftops seem a good place to put the machinery. My next job is to find some figures for a large-scale solar farm, and see how they compare.

 

The installed capacity of wind power in this country is 25.5 GW. The actual output last month averaged 6.2 GW, roughly a quarter, with a high of 15 GW (60% of capacity) and a low of 690 MW (2.7%). The installed capacity of nuclear capacity is now under 6 GW. The actual output last month averaged 4.5 GW (about 75% of capacity) with a high of 5.5 GW (92% - surprised me too) and a low of 3.9 GW (65%). Doubling the capacity of nuclear would have meant no gas at all being needed in electricity generation for about 7 days last month, and we could begin to think about making inroads into converting transport and heating from fossil fuels to electricity.