UK energy

[roubaixtuesday]

Rather than speculate about the evils of capitalism, does anyone know exactly what is happening with hydro generation?

It seems rather unlikely that companies are deliberately throwing away free revenue by letting water available for generation waste over spillways.

Unless there is some peculiarity whereby they are being paid *not* to generate?

The obvious alternative is that the use of available water is maximised at peak times if price (ie peak time of day), which would be a good thing, minimising despatchable gas burning.

Anyone able to answer with more than just speculation?

[rjb]

When I worked in the industry plant was often paid to be available and not generating. Known as spinning reserve to enable generation to be put on the grid if there was a fault which caused a generator to trip off the grid. The last remaining coal plants used to perform this function in the depths of winter. The cost of having spinning reserve is substantial as it involves having generating plant fully staffed sitting idle for most of the year or just spinning with everything running. Hydro plant and backup batteries may now be carrying out this duty. To protect the grid spinning reserve used to be approx 5 % of the max predicted generation.
This was why Dinorwic was built originally as a backup which could be generating within 2 minutes of a large 500mw unit tripping from a power station. Subsequently sold off and now run to maximise profits for shareholders .

[PDQ Mobile]

Water is pumped from large reservoirs Wales in Wales to supply Birmingham .
Wondering what the drop on the network is that supply said water .Is it enough the place in line turbines . This water must be pumped under pressure. Cost to benefit ratio not there?
How much fall is required to make any scheme viable ?

Drinking water reservoirs
.
I was curious about Llyn Celyn, not so far from here so had a look online.
It was at the time of its construction in the 60's highly contentious and sort of remains so.
https://en.wikipedia.org/wiki/Llyn_Celyn

I had always thought it was constructed (solely) to provide Liverpool with drinking water, which is the case (not directly by pipeline but is extracted downstream- it regulates the level of the Dee), and I wondered why it wasn't used for leccy generation.

It does, however, have some installed Hydro, 4.5 MW to be precise.
Pretty small amount for such a big lake 71,200,000 cubic meters, and has around a 50 meter head at the dam.
Indeed it generates only just over 8 times that of little and much maligned Sandford.

(Llyn Celyn's water holding is around a fifth of the massive Grand Dixance in Switz - which generates 2000MW though obviously the fall is much greater there, though the precipitation may not be)

The base of the Celyn dam is 265 metres above sea level.
.........
A large construction project is at this moment underway at the dam to build a new overflow spillway to supplement the existing one which has not flowed since the 1970's.
For an event considered likely to occur 0.01 times in any one year.
I leave this for the panel to dissect.
https://corporate.dwrcymru.com/en/commu ... llyn-celyn

[Jdsk]

A tidal lagoon sounds good but just how much energy output will we get for the investment?
...

House of Commons Library: "Tidal lagoons":
https://commonslibrary.parliament.uk/re ... /cbp-7940/

NB date.

New proposal: "West Somerset Lagoon", 2,5 GW "maximum output":
https://www.theguardian.com/environment ... rset-coast
complete with cycle track:



Happy Christmas

Jonathan

[Carlton green]

I find that Guardian links are blocked to me: either accept our targeted advertising or give us your money.

This link, by the scheme’s proposers, is free to use: https://www.westsomersetlagoon.com/ .

I’ve mixed views on such a tidal lagoon scheme and similarly to wind and solar it really needs some energy storage (massive batteries) with it too. Has the UK really got the ability to deliver such a massive project to time and to budget? The track record suggests to me that if completed it’ll come in late and substantially over budget, and we’ll likely struggle to find labour to build it too.

At 15 Km that’s one long wall …. and an awful lot of quarried material from somewhere too …. Green? Well, it depends on how you look at it.

Why the English side of the channel rather than the Welsh?

[Cugel]

I find that Guardian links are blocked to me: either accept our targeted advertising or give us your money.

This link, by the scheme’s proposers, is free to use: https://www.westsomersetlagoon.com/ .

I’ve mixed views on such a tidal lagoon scheme and similarly to wind and solar it really needs some energy storage (massive batteries) with it too. Has the UK really got the ability to deliver such a massive project to time and to budget? The track record suggests to me that if completed it’ll come in late and substantially over budget, and we’ll likely struggle to find labour to build it too.

At 15 Km that’s one long wall …. and an awful lot of quarried material from somewhere too …. Green? Well, it depends on how you look at it.

Why the English side of the channel rather than the Welsh?

I have no views on tidal lagoons as I don't know enough about them. I suspect that this is true of 99.999% of the population. Still, everyone has to have an opinion on everything, these days. Wot a good job the newspaps and other mass media pot them up for us to buy and regurgitate, eh?

[rjb]

news is in short supply hence these previously rejected projects are being announced as the next best thing in energy storage. The Swansea bay lagoon was on the verge of being built, planning permission granted until the funding dried up as it wasn't deemed to be financially viable. I think this is where this one is destined to go . Other projects which slipped away include lagoons on the Mersey, Colwyn bay and the severn barrage. Not during my lifetime i fancy will they come to fruition.
you can find more further up in this thread. Heres a reminder,

al_yrpal wrote: 22 Oct 2023, 8:40am
At last, the govt takes tidal power seriously....

https://www.bbc.co.uk/news/science-environment-67170625

Al
I think the problem, as always, is the investment.

This one below, however, we are told will happen. It's the third attempt at the Swansea tidal lagoon, but this time we are being told that it: "appears to be fully funded by the private sector".

https://www.newcivilengineer.com/latest ... 6-01-2023/

And the bad news? They say it will take 12 years to build all three phases

[axel_knutt]

It seems rather unlikely that companies are deliberately throwing away free revenue by letting water available for generation waste over spillways.

What water? What waste?

Most reservoirs are for drinking water, and only overflow in times of flood. You can't throw drinking water away just to generate power, and it's not economical to build power stations that sit doing nothing except in rare flood conditions.

This was why Dinorwic was built originally as a backup which could be generating within 2 minutes of a large 500mw unit tripping from a power station.

Dinorwic (and Ffestiniog & Cruachan) don't generate any net power, they're pumped storage systems that use offpeak electricity to pump water uphill for smoothing demand on the grid at peak times.

Water is pumped from large reservoirs Wales in Wales to supply Birmingham .
Wondering what the drop on the network is that supply said water .Is it enough the place in line turbines . This water must be pumped under pressure. Cost to benefit ratio not there?
How much fall is required to make any scheme viable ?

You can't generate any net energy from water that's already been pumped using electricity, that would amount to a perpetual motion machine. The energy 'generated' must always be less than that used, which is why pumped storage systems are net consumers of electricity (like batteries), and are called storage stems not generating systems.

I can't see any reason why drinking water pipelines would use anything other than gravity where it's available, and an absolute minimum of electricity for pumping when it isn't. The Elan valley reservoirs are 73 miles from Birmingham, with a gravity fed aqueduct that has a fall of 1 in 2,300 and a speed of under 2mph. I would have thought that's barely enough to overcome friction, let alone anything left over for generating power.

https://en.wikipedia.org/wiki/Elan_aqueduct

[Jdsk]

news is in short supply hence these previously rejected projects are being announced as the next best thing in energy storage.
...

The proposal is predominantly for generation, not storage.

Jonathan

[Carlton green]

news is in short supply hence these previously rejected projects are being announced as the next best thing in energy storage.
...

The proposal is predominantly for generation, not storage.

Jonathan

Well, you could truthfully say that but on the outgoing tide stored water is used to generate power and on the incoming tide a store of empty space is used to generate power. In both cases the store would, if only used then, produce peak power at high and low tides respectively (because that would be the time of maximum head difference). I believe that in the proposed installation, as the tide flows into and out of the barrage under a low head, electricity is generated for longer but (I anticipate) with less KWh than would be the case if it were only discharged and admitted at the extremes of the (that day’s) tidal range.
TLDR: It’s potential energy stored either side of the lagoon wall that allows generation.

I have no views on tidal lagoons as I don't know enough about them. I suspect that this is true of 99.999% of the population. Still, everyone has to have an opinion on everything, these days. Wot a good job the newspaps and other mass media pot them up for us to buy and regurgitate, eh?

You can’t go wrong with the Grundian though, eh. Me, I just say we’re all: deliberately ‘socially’ conditioned, misinformed, misguided, misdirected and misused; an upsetting realisation but sadly it is exceedingly true.

[Jdsk]

A storage system is intended to store energy from another source of power generation. A generating system may store energy in some stage of the process before it's delivered as useful electricity, and *many types do. But that's not a good reason for obfuscation.

Jonathan

* And possibly all... can anyone suggest a power generating technology that doesn't include "storage"?

[Carlton green]

A storage system is intended to store energy from another source of power generation. A generating system may store energy in some stage of the process before it's delivered as useful electricity, and *many types do. But that's not a good reason for obfuscation.

Jonathan

* And possibly all... can anyone suggest a power generating technology that doesn't include "storage"?

Tidal stream, solar and wind turbines do not store energy, they extract energy from what is freely and unconstrained around them. Hydro electric schemes store potential energy and tidal barrage is arguably a form of hydro electric scheme.

Most hydroelectric power comes from the potential energy of dammed water driving a water turbine and generator. The power extracted from the water depends on the volume and on the difference in height between the source and the water's outflow. This height difference is called the head. A large pipe (the "penstock") delivers water from the reservoir to the turbine.[25]

https://en.wikipedia.org/wiki/Hydroelectricity

[tim-b]

A storage system is intended to store energy from another source of power generation. A generating system may store energy in some stage of the process before it's delivered as useful electricity, and *many types do. But that's not a good reason for obfuscation.

Jonathan

* And possibly all... can anyone suggest a power generating technology that doesn't include "storage"?

The only obfuscation is because governments don't want us to think outside the box. We only need this scheme because of the AI boom; the real question is whether that boom really is a good thing. It seems to be slated as the next bubble to burst.

Is cooling AI using sea water a good thing for our warming environment?

Storage should be the future, but the problem is the enormous upfront cost of renewable power generation with the cost of battery energy storage systems (BESS) on top.

Balancing your power grid is essential and, as we head more towards renewables, the loss of spinning generators means that we lose controllable inertia and that must be replaced. Just ask Spain and Portugal (2025) or South Australia (2016).

The technology exists, e.g. BESS and synchronous condensers.

With a total capacity of 600MWh, Thurrock Storage is capable of powering up to 680,000 homes, and can help to balance supply and demand by soaking up surplus clean electricity and discharging it instantaneously when the grid needs it. https://www.nationalgrid.com/national-g ... substation

This government hasn't got a plan and that's the simple truth.

What's happened to Great British Energy, they haven't filled the post of Director of Strategy yet. https://www.gbe.gov.uk/sites/default/fi ... 202025.pdf

[wheelyhappy99]

the enormous upfront cost of renewable power generation

Reading page 24 may be helpful.


https://assets.publishing.service.gov.u ... s-2023.pdf

[tim-b]

the enormous upfront cost of renewable power generation

Reading page 24 may be helpful.


https://assets.publishing.service.gov.u ... s-2023.pdf

A summary of the point that you're making would be more helpful.

A quick glance shows that pre-development costs are 2x or 3x that of gas turbines and construction costs are 3x or 4x

My point was that this government doesn't have a plan.

AI isn't a good thing for growth according to some economists and so this specific project isn't needed for that.

Consequently, predicted TFP gains over the next 10 years are even more modest and are predicted to be less than 0.53%. https://www.nber.org/papers/w32487

We need to balance our power grid to prevent power cuts and we need to pay for BESS and other mechanisms to achieve that, which isn't cheap, rather than generation for unnecessary AI.

We already have the most expensive industrial energy costs in Europe, so gas turbines aren't the long-term future, we all know that