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Author Topic: Aberthaw Power Station and Decarbonisation  (Read 26280 times)
PhilWakely
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« Reply #225 on: September 17, 2021, 05:28:21 pm »

It was surprisingly difficult to find pictures of the NG (Natural Gas) prototype line with its realistic wires, as opposed to CGI (Computer-generated imagery). However, this is one from the designers, Bystrup;


If those are National Grid wires, they are extremely low!
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stuving
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« Reply #226 on: September 17, 2021, 05:45:13 pm »

If those are National Grid wires, they are extremely low!

How are you judging scale so as to decide that? HV grid wires always look lower than they are, partly because they are thicker wires than your imagination tells you. The T-pylons are shorter, but that's mainly due to the lack of a pointy top and the triangular arrangement of the wires being more compact than vertical stacking. I'm sure the limit of vertical clearance for 400 kV is still the same.
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Bmblbzzz
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« Reply #227 on: September 17, 2021, 08:21:41 pm »


Of course some people are hard to please - this Guardian article maintains they are so boring as to be no better than the old lattice ones:
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Designed by Danish architect Bystrup, the T-pylon is shorter than the lattice of old, which is achieved by stringing the wires in a triangular configuration. However, the style feels somewhat safe, as if to appease the detractors – after all, barely anyone objects to lamp-posts. What a wasted opportunity to drop more innovative sculptures across the landscape.

As professional detractors, they should know ...
I'm not sure anyone called Flash should be trusted with anything electrical!
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broadgage
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« Reply #228 on: September 18, 2021, 03:08:22 am »

Those insulators look inadequate to me. Are they actual photographs or "artists impressions" ?
 
High voltage insulators need not just enough clearance for the voltage, but also a generous "creepage length" along the insulator. This is typically achieved by a number of discs so arranged as to present a very long creepage distance.
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A proper intercity train has a minimum of 8 coaches, gangwayed throughout, with first at one end, and a full sized buffet car between first and standard.
It has space for cycles, surfboards,luggage etc.
A 5 car DMU (Diesel Multiple Unit) is not a proper inter-city train. The 5+5 and 9 car DMUs are almost as bad.
Oxonhutch
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« Reply #229 on: September 18, 2021, 08:17:02 am »

I hope that top connection to the tee arm is stronger than it looks. The engineer-bit in me senses two single points of failure.
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stuving
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« Reply #230 on: September 18, 2021, 11:19:00 am »

Those insulators look inadequate to me. Are they actual photographs or "artists impressions" ?
 
High voltage insulators need not just enough clearance for the voltage, but also a generous "creepage length" along the insulator. This is typically achieved by a number of discs so arranged as to present a very long creepage distance.

Well, that is - or at least is claimed to be - progress. Broadgage, I think, has been misled by the scale of the things - as we all are. Here are a couple of pictures from Allied Insulators, who are the ones claiming cleverness credit of them. One has people in, to show the scale, but the insulators are covered. The second shows that they do have all the usual features, including track-lengthening corrugations. 



I hope that top connection to the tee arm is stronger than it looks. The engineer-bit in me senses two single points of failure.

All change has consequences, and the art of good engineering is to foresee all the adverse ones and prevent them or stop and try another approach. Of course you can never know whether an unforeseen consequence is adverse, so you need to foresee all of them to find out!

I'd agree with broadgage's general view that a lot of recent designs (not just trains) have done badly in this respect, even appearing to be unaware of things that not long ago all designers knew. I don't share his view that there is a Rosicrucian cell skulking in the basement of DfT» (Department for Transport - about) Towers plotting to make life as miserable as possible for rail travellers in general, and broadgage in particular, as a prelude to shutting down the railways.
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TonyK
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« Reply #231 on: September 18, 2021, 09:55:40 pm »

I go away for a week and come back to a foreign country, where nothing seems as I left it.

A friend (who works in nuclear power) pointed me at this interesting resource which shows carbon intensity of electricity generation by country. Obviously it doesn't quite tell the whole story, but it does lend weight to the view that the quicker we get a few new nuclear power stations going the better...

I couldn't agree more, Red Squirrel, and that "illegal subsidy" strike price of £92.50 per MWh looks a real bargain now.

I have mixed feelings about nuclear power.
It should be a good idea, but I have doubts as to the practical application.

I do not trust chinese involvement from either the quality control point of view or for national security reasons.
And as for japan, if they cant build a decent train then I don't want a nuke from them.

I would have more faith in UK (United Kingdom) designed and built reactors, but could we build them these days ?

Hinkley C is years late and will no doubt go furthur over budget.

I think the past 60 years show that nuclear power is practical. It is even more so now for a number of reasons. Firstly, we probably won't need to make any more plutonium for bombs for a long time - I would much prefer that we used it as fuel instead. This gives us a lot more choice over design - the Magnox reactors were inefficient in using the fuel because of the need for plutonium. That leads to the second point - we know a great deal more about nuclear energy than we did 60 years ago, even if we did run down the skills set somewhat. The choice of materials is easier to make now when know what various types of concrete and steel look like after being bombarded by neutrons for a few decades. How we deal with what is currently termed waste, but which may prove to be fuel has improved enormously.
The third point is competitiveness. Nuclear can already match wind and solar for safety, but can beat them soundly in terms of reliability. I was laughed at some time ago for saying that the limitations of renewables would become more apparent as more came on line and we got closer to beginning to fase out phossils. Seems I was right, although that has yet to stop the snake oil merchants from flooding social media with stories about how they are going to store all the excess renewable power in batteries or make hydrogen with it. We need a supply of energy that is reliable and controllable, and if we don't want gas or coal in the mix, it will have to be nuclear.
Brings me nicely to the fourth point - yes we can build them. Hinkley C seems to be going to plan, and is having something of an, er, electrifying effect on confidence in the nuclear engineering sector. At the top is a man with wild hair who works out what goes bang when what hits what, and how best to keep it under control. The pyramid expanding below is about engineering in the truest form, applying lessons learned in materials and techniques. An awful lot of people have been grafting away on Hinkley C for a long time, with apprentices watching their every move. Sizewell C should be relatively straightforward for them - if it gets built. That's really down to the financial modelling at the moment, which, as RS says, is the really complicated bit. We won't get Hinkley C terms again - I share broadgage's view that the price will rise, but remember - we don't pay until it starts running.
I say "if" Sizewell C is built. I think it will be, but other technologies are in the ascendancy. Rolls-Royce has designs for small modular plant, built in a factory and transported (if they can find a lorry driver) to a suitable site. Next to a closed coal power station or nuclear plant will do fine. They are off-the-shelf, just add a couple more for extra power. Thorium is back in vogue, as are molten salt reactors.


It has all gone orribly wrong WRT (with regard to ) natural gas price and supply in the UK.
Wholesale gas it at present trading at 140 pence a them. And has been for some days. That is about FOUR times the usual price at this time of year, and substantially in excess of the last peak price of 82 pence a therm.

Russia is restricting supplies, and various Asian countries are outbidding us for LNG cargoes.

In the near term, this is bad news for the environment as coal burning has increased, West Burton coal power station is back in use for example.

In the longer term, prices like this are good news for the climate as use of gas is discouraged and renewables become more economic. Two domestic energy retailers have gone bust, due to paying much higher wholesale prices and being unable to pass this on promptly to consumers. Others are expected to follow.

Although gas prices are greatly increased, there are not YET any physical shortages in the UK.

If supplies remain adequate but at today's price then I expect retail gas prices to at least double, and electricity prices to increase by at least 50%

If significant physical gas shortages occur, then I expect that HMG will bring in emergency regulations to limit consumption, and that large scale power cuts will result. GAS cuts are unlikely for safety reasons, It is ELECTRICITY supplies that would be at risk in any serious gas emergency.

It has gone horribly wrong, although it was not a surprise to some commentators. The renewables companies are saying that it has been 20% less windy than expected, which has had a big impact on their profits output. We aren't the only ones trying to close coal plants down, although I can see the closure plans being slowed a little, meaning more gas has been needed. Russia and China are replenishing stocks in the same way as some people buy toilet paper when told there is no cause for alarm. Both are looking to increase production generally, adding pressure. We produce nearly a half of our own gas, with most of the rest coming from Norway and Qatar. That last is especially subject to price volatility, being delivered by ships that can change course if they get a better offer. As much of our electricity is derived from gas, the price of that goes up when the price of gas rises. The price of uranium is also rising, but as a stock the size of a suitcase will power a 3 GW (Great Western) reactor for a month, the effect isn't so marked. India intends to build a Thorium reactor, with the fuel being extracted from sand - not a scarce product in India.

I am not sure how this can be of long term benefit for renewable energy. The price of that will begin to rise again, and bigly so in the event of installation supplies from any country using cheap forced labour being banned from the market. The price of the backup generators is already up.

As part of my job, I look into energy deals for consumers. The big savings have vanished, with deals offering much the same prices as the capped standard variable tariffs. Some are even charging more than the SVT. I wouldn't let that put you off signing up to a fixed deal. The SVT cap is about to go up, and many commentators expect a further 20% rise next spring. They also predict that we will be down to 10 or so suppliers within months. Some small ones are already trying to sell their domestic customers, but the big boys seem content to just let them fail and be appointed by Ofcom to take over. That saves a lot of angst with TUPE (The Transfer of Undertakings (Protection of Employment) Regulations 2006.), pensions, credits due to consumers etc.

Those insulators look inadequate to me. Are they actual photographs or "artists impressions" ?
 

I'll bet you a pound to a sufficiency of port that they have been tested to a specification well beyond necessity. I rather like the design, although I am yet to see one "live", as it were. I have certainly seen a lot of work going on adjacent to the M5, and on passing through Tickenham. I find it rather exciting. I bet most people have no idea what is going on. Not everyone is in favour, but remember that the original lattice pylons won a design competition. They look rather dated now, with many being in their 70s.
« Last Edit: September 18, 2021, 10:56:33 pm by TonyK » Logged

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eightonedee
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« Reply #232 on: September 18, 2021, 10:49:24 pm »

While I agree with most of what TonyK says......

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Seems I was right, although that has yet to stop the snake oil merchants from flooding social media with stories about how they are going to store all the excess renewable power in batteries or make hydrogen with it.

I am not so sure that this is all snake oil - the hydrogen bit perhaps, as it seems extraordinary that something that seems to take so much energy to produce in the first place is so far up (apparently) the agenda. Everyone seem fixated with the "only water out of the tailpipe" bit that they ignore the energy used to get the fuel in the first place.

But I have heard credible professional people talk about battery farms to help deal with the uneveness of renewable wind, and that there is now an active search for sites convenient to the North Sea. This seems just to be the 21st century equivalent of the municipal gas holder.
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TonyK
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« Reply #233 on: September 18, 2021, 11:13:48 pm »

While I agree with most of what TonyK says......

Quote
Seems I was right, although that has yet to stop the snake oil merchants from flooding social media with stories about how they are going to store all the excess renewable power in batteries or make hydrogen with it.

I am not so sure that this is all snake oil - the hydrogen bit perhaps, as it seems extraordinary that something that seems to take so much energy to produce in the first place is so far up (apparently) the agenda. Everyone seem fixated with the "only water out of the tailpipe" bit that they ignore the energy used to get the fuel in the first place.

But I have heard credible professional people talk about battery farms to help deal with the uneveness of renewable wind, and that there is now an active search for sites convenient to the North Sea. This seems just to be the 21st century equivalent of the municipal gas holder.

I am glad that at least two of us realise this. I am told in other less learned places that batteries will save us all by storing all the excess renewable energy and using it to run the country when the wind ain't playing ball. You and I know this is nonsense. The batteries - some are already in place - have the twofold purpose of evening out the flow as you describe, and being ready to restart the national grid in the event of total failure - a so-called "black start". This doesn't stop companies placing stories in social media about how they  can store all this energy. The comments are then quickly filled with cries of joy at how this will keep us going through those frequent stalled high pressure times, with nothing being done to dispel the notion. This is not accidental. Why would such a company advertise a 5 GWh monstrosity to be placed in a beauty spot near you - do they expect us to start clubbing together to buy one for our village? No - it's to remind us to tell our MPs (Member of Parliament) that we want the government to subsidise more batteries.

There will be a number, probably near those big junction box things like the one near Melksham. They will most likely be fully charged at all times, however the grid is being supplied.
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« Reply #234 on: September 19, 2021, 04:58:14 pm »

I am more optimistic about utility scale batteries than some people.

Whilst the existing and proposed batteries are small in relation to demand, that is in my view comparable to saying that the railways of 1830 were of little relevance, or that petrol cars of 1900 would never be used on a significant scale.

Even a battery able to deliver 5 GW (Great Western) for an hour is a very useful addition to the grid. It could supply 10% of the winter peak demand for an hour, rather than running gas gobbling OCGT (Open Cycle Gas Turbine) plant for that hour.
Another 1 GW of battery capacity would a useful emergency reserve at any time of day if something breaks. The intention in such a case is to "bridge the gap" between a failure and the starting of other generating plant. One GW from a battery is far preferable to blacking out a million people.
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A proper intercity train has a minimum of 8 coaches, gangwayed throughout, with first at one end, and a full sized buffet car between first and standard.
It has space for cycles, surfboards,luggage etc.
A 5 car DMU (Diesel Multiple Unit) is not a proper inter-city train. The 5+5 and 9 car DMUs are almost as bad.
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« Reply #235 on: September 19, 2021, 06:25:07 pm »

I largely agree with Tony I would just question a couple of points.

Nuclear can already match wind and solar for safety, .....

I am concerned that we are getting a bit complacent on this since we haven't had a major incident from a UK (United Kingdom) reactor since 1957.  As we change our technology in the way Tony describes we the potential for new types of failure. (for example molten salt sounds like it could have challenges for materials).  However, the major risk that concerns me is a repeat of Fukushima Daiichi disaster which was caused by a tidal wave. I know we are not in an earthquake zone but tidal waves are a known risk in the UK - Bristol Channel 1609 and the projected risk from an expected cliff collapse on the canaries has been modelled as affecting the UK.  The problem is that many of our nuclear sites on low level sites on the coast. 

I was laughed at some time ago for saying that the limitations of renewables would become more apparent as more came on line and we got closer to beginning to fase out phossils.

I agree this is always going to be a problem with wind and solar, but we have not exploited tidal power, despite being blessed with some of the best possible sites.  Tidal is much more predictable and if geographicall diverse around our coasts can give a consistent supply. 
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TonyK
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« Reply #236 on: September 19, 2021, 09:03:28 pm »

I largely agree with Tony I would just question a couple of points.


I am concerned that we are getting a bit complacent on this since we haven't had a major incident from a UK (United Kingdom) reactor since 1957.  As we change our technology in the way Tony describes we the potential for new types of failure. (for example molten salt sounds like it could have challenges for materials).  However, the major risk that concerns me is a repeat of Fukushima Daiichi disaster which was caused by a tidal wave. I know we are not in an earthquake zone but tidal waves are a known risk in the UK - Bristol Channel 1609 and the projected risk from an expected cliff collapse on the canaries has been modelled as affecting the UK.  The problem is that many of our nuclear sites on low level sites on the coast. 

Luckily you are not the only one who thought about this. EDF's Hinkley C website tells us that:

Quote
As with all of our operational nuclear power stations across the UK, the design basis for Hinkley Point C ensures that the proposed plant is secure against natural hazards that have a frequency of less than one in 10,000 years. These hazards include tides, storm surges and tsunami as isolated and in-combination events.

To protect the Hinkley Point C station from such events, the platform level of the site is set at 14.0 metres above sea level, behind a sea wall with a crest level of 13.5 metres. Sea level rise which could result from future climate change has also been considered and an allowance has been made to cover the full 60 year operating lifetime of the new station.

The FAQs (Frequently Asked Questions) don't specifically address the point, but I will wager that thee emergency diesel generators to keep the pumps running in the event of loss of power will be somewhere where they won't be swamped by the same tsunami. It was that which did for Fukushima - the initial reserve was in a basement in the complex, and the additional backup generators were not high enough above sea level.

In re the Canary Islands tsunami risk relates to the Cumbre Vieja volcanic region on La Palma (lovely place), which could deposit a lump of rock about the size of the area between Bristol and Weston super Mare into the Atlantic without notice. I noticed, when looking up the name, that recent studies have downgraded the likely effect of this from a cataclysmic tsunami that would flood the entire eastern seaboard of the US for ten of miles inland, and make Glastonbury an island again, to a few wellington boots being overtopped at the seaside. I have no idea if this is true, but we might find out soon. The volcano that might trigger the event has just begun to erupt again. I'm going to the Canaries on holiday in January and February if they are still there.

I was laughed at some time ago for saying that the limitations of renewables would become more apparent as more came on line and we got closer to beginning to fase out phossils.

Quote
I agree this is always going to be a problem with wind and solar, but we have not exploited tidal power, despite being blessed with some of the best possible sites.  Tidal is much more predictable and if geographicall diverse around our coasts can give a consistent supply. 

I am genuinely puzzled by the non-appearance of wave power. I don't subscribe to the usual conspiracy theories about the oil companies suppressing it, as surely they would have nobbled wind and solar, unless they thought they were not a threat to their existence (which they aren't - quite the opposite). I am beginning to think that there is some major natural or engineering obstacle in the way, that we haven't been told about because it might cause funding for research to dry up. If so, it could well be that the financiers and insurance companies are reluctant to get involved. Suppose they spent £100 billion on the Severn Barrage, and it wrecked the ecological balance of the whole of South Wales, Gloucestershire, Bristol and Somerset?  Maybe it is too big an unknown risk for them in a way that nuclear isn't.

« Last Edit: September 24, 2021, 12:22:09 pm by TonyK » Logged

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ellendune
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« Reply #237 on: September 19, 2021, 09:40:35 pm »

I am genuinely puzzled by the non-appearance of wave power. I don't subscribe to the usual conspiracy theories about the oil companies suppressing it, as surely they would have nobbled wind and solar, unless they thought they were not a threat to their existence (which they aren't - quite the opposite). I am beginning to think that there is some major natural or engineering obstacle in the way, that we haven't been told about because it might cause funding for research to dry up. If so, it could well be that the financiers and insurance companies are reluctant to get involved. Suppose they spent £100 billion on the Severn Barrage, and it wrecked the ecological balance of the whole of South Wales, Gloucestershire, Bristol and Somerset?  Maybe it is too big an unknown risk for them in a way that nuclear isn't.

I wonder if they spent too much time following up the mega-schemes such as the Severn Barrage and so aren't as far ahead with the more realistic options. 
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Bmblbzzz
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« Reply #238 on: September 20, 2021, 09:31:21 am »

What I note from https://www.electricitymap.org/map is that the 'greenest' areas are mostly powered by hydro. This is an energy source that never gets talked about here. Do we not have any suitable rivers?
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« Reply #239 on: September 20, 2021, 10:06:41 am »

Hydropower needs either a vast flow of water and a modest drop in height, or a reasonable flow and a large drop in height.
All the best sites for large scale hydro are already in use.
There is potential for increasing peak capacity at existing sites. The total energy produced in a year is limited by the amount of water, but 1,000 MW for a few peak hours a day is a lot more valuable than 100 MW 24/7.

There is potential for more small hydroelectric plants, but these wont make much difference nationally.

As an example, I am aware of one rather public site, Bishops Mill in Salisbury. Many non technical people observed the water flow and reached most optimistic views as to the amount of electricity that could be produced.
"Could power the hospital"
"Use it to power electric trams"
"Cheap or free electricity for the poor"

In fact the potential output was about 7 kw, enough for one not very good electric shower. or perhaps for two all electric homes, if energy efficient and with thermal storage water heating and space heating.
The value of the electricity would be about £1 an hour. That would take a while to repay any significant capital costs.

In a post apocalyptic world 7 kw could power a small town with very careful use. 1000 homes at 7 watts each. Six one watt  LED bulbs per home and a transistor radio. That is more light than most of our ancestors had. And in daylight, 7 kw could  pump water to an elevated tank, grind grain, or power other machinery.
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A proper intercity train has a minimum of 8 coaches, gangwayed throughout, with first at one end, and a full sized buffet car between first and standard.
It has space for cycles, surfboards,luggage etc.
A 5 car DMU (Diesel Multiple Unit) is not a proper inter-city train. The 5+5 and 9 car DMUs are almost as bad.
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