Green, ethical, energy issues in the news

ABrass

michaels said:

ABrass said:

michaels said:

Exiled_Tyke said:

So green hydrogen isn't a silver bullet when it comes to domestic heating.  In fact according to this article it works out six times more expensive than using a heat pump. Ouch!!! 

https://www.bbc.co.uk/news/science-environment-63050910

Surely the reason for using hydrogen is that it is also a storage medium and if the electricity is 'free' spill then even very low efficiencies still make sense?  Or am I missing something?

(Of course H2 to the home may not be the best way of storing then consuming the spill, it may be better to burn the H2 in power stations and use heat pumps but the analysis is much more complicated than simply you get 6 times as much heat energy from wind electricity straight to heat pump than you do if you go via H2)

[Second aside, if you have H2, do you get more heat by burning it in a boiler of using a fuel cell to convert to electricity and running a heat pump?]

In theory spillage power would make sense, but apparently the cost of the splitters is high enough that you need high utilisation rates for them to make sense financially.

Fuel cells are more efficient than combustion engines using hydrogen.

I found several references to fuel cells beat h2 ice but couldn't find efficiencies for H2 power stations - might they be similar to gas at up to 60-70%?. 

Obviously we already have a gas distribution network, perhaps it would make sense to use it to distribute H2 to domestic fuel cells to power heat pumps?

The gas network isn't capable of handling pure hydrogen at the moment. It would require a lot of work to upgrade it to that point. I think the difficulty is mentioned in the report.

Martyn1981

michaels said:

ABrass said:

michaels said:

Exiled_Tyke said:

So green hydrogen isn't a silver bullet when it comes to domestic heating.  In fact according to this article it works out six times more expensive than using a heat pump. Ouch!!! 

https://www.bbc.co.uk/news/science-environment-63050910

Surely the reason for using hydrogen is that it is also a storage medium and if the electricity is 'free' spill then even very low efficiencies still make sense?  Or am I missing something?

(Of course H2 to the home may not be the best way of storing then consuming the spill, it may be better to burn the H2 in power stations and use heat pumps but the analysis is much more complicated than simply you get 6 times as much heat energy from wind electricity straight to heat pump than you do if you go via H2)

[Second aside, if you have H2, do you get more heat by burning it in a boiler of using a fuel cell to convert to electricity and running a heat pump?]

In theory spillage power would make sense, but apparently the cost of the splitters is high enough that you need high utilisation rates for them to make sense financially.

Fuel cells are more efficient than combustion engines using hydrogen.

I found several references to fuel cells beat h2 ice but couldn't find efficiencies for H2 power stations - might they be similar to gas at up to 60-70%?. 

Obviously we already have a gas distribution network, perhaps it would make sense to use it to distribute H2 to domestic fuel cells to power heat pumps?

Hi. I think you've answered your own question. Let's say we store the excess RE as H2. This will happen after the simpler, faster and more efficient intraday storage has been filled, such as batts, PHS, LAES, flow batts(?) and anything else that comes along.

Then despite any inefficiencies in longer term storage, like H2, CAES, it's still worth storing it for (I'm just spitballing here) 10hr+ storage as we move ever deeper into RE generation/penetration.

So, personally, I can definitely see H2, or something with similar potential, being rolled out for storage, especially as H2 is needed for so many other purposes already, like fertiliser, and steel production going forward.

So at that point, do we try to upgrade the UK's gas mains and boilers to operate on H2, at perhaps 90% efficiency for space heating, or as you mention, run it through (existing?) gas power stations at perhaps 60%+ efficiency? Let's say after transmission and distribution network losses, we get 55% of the original H2 energy to a house, then run it through a heatpump at a COP of 3, then we get 1.65 units of heat, v's the 0.9 from the H2 boiler.

Regarding the home fuel cell, I did post a couple of years ago a vid about home fuel cell boilers, I think the company was called Star, I'll track it down and post. If I remember correctly the FC boiler was about 50% efficient at producing leccy, with about 30% heat. My suggestion at the time, was that this gave you some heat, and leccy (when PV gen would be low), and co-located with batts and a heat pump (as you mention) may make a good all round package.

However, we are now talking HP (with leccy from the grid), v's gas mains upgrade, plus FC boiler, plus the HP anyway.

No idea what will work out, but IMO, the distributed H2 solutions seem overly complex. And my suggestions about the FC boiler mix, were based on the fact they can operate on methane, so I thought that might be a partial solution, if we produce synthetic methane from that green H2 plus captured CO2. But again, that suggestion adds another tech step.

HP's and leccy (including from stored H2) just seems very simple going forward.

Edit - Well that was easier than I expected, but much earlier than I thought, 4.5yrs ago:

Star Heat Pumps | Fully Charged

Martyn1981

Just read this article and thought it was excellent for its simplicity at setting out what is needed to reach ~100% low carbon leccy by 2030. It's a bit political, ignore that, and pushes back at the DT for knocking the figures.

But for me it helped to confirm my feelings that it's possible. It points to a 3% shift to RE each year since 2020, which is fair, and suggests that needs to rise to 5% for us to reach ~100% low carbon leccy by 2030 - that also seems fair. And it's worth repeating some waffle I've posted recently that the 2019 CfD auction adds ~7% just from new off-shore wind, and the 2021 (results this July) CfD adds 10% just from off-shore wind, so I'd suggest we could (or are) closer to +5%pa looking at the rest of this decade.

As I said, don't worry about the views/opinions, just a quick article setting out figures for 2030, which are looking good, I think, regardless of whether Labour or the Conservatives roll it out.

Will Labour’s energy plans work?

The UK’s low-carbon electricity sources are already saving huge amounts of gas: In 2022 to date, nuclear and renewables have generated 129TWh, more than the 95TWh we got from gas.

In line with the clear consensus that cheap renewables will make up the bulk of electricity supplies in the future, Labour sees wind and solar making up about 70% of the electricity mix in 2030.

Almost all of the remaining 30% of the nation’s electricity would come from a mixture of other low-carbon sources including additional new nuclear plants, other renewables and hydrogen.

The modelling then leaves a very small share – about 0.7% of annual electricity in 2030 – coming from gas power. A further 0.5% would come from gas plants fitted with carbon capture equipment that prevents their carbon dioxide emissions from reaching the atmosphere.

Coastalwatch

Listened to a webinar on results from a half years finances from a battery storage group this morning and the very last question asked was about what did they see to accompany batteries in 5 -10 years to cover long term storage. The fund manager said it was something they were constantly reviewing but as of now 95% of our needs will be met by renewables, nuclear and batteries etc with only 5% then to be covered for the longer periods. They can see nothing emerging presently and suggests the most economical solution is gas. He appreciated it would an unpopular choice given recent events but until much simpler processes for hydrogen generation become available it just didn't make sense to consider it.

michaels

Another article on moving to 99% RE by 2030 - perhaps it is the same source as the Labour plan?

Here’s how the UK power sector could ditch 99% of natural gas by 2030 (electrek.co)

Martyn1981

Yeah, really positive news. I do like a good target, but they are often meaningless without annual figures and steps. But, in the case of UK leccy, it really does look like we are on course to ditch gas this decade, with steady annual progress.

Assuming nuclear stays at about 20% this decade, with HPC replacing the roughly similar end of life closures, then with gas already below 40%, we 'only' need that +5% from RE each year, which not only seems possible, but is perhaps roughly what's happening now.

This is going to be very interesting to watch/follow. Hopefully this year RE will be at 45%+. Then we have the next CfD round as they move to annual auctions, more support for PV (well, less negatives for PV), and similar for on-shore wind if the Gov reduce/drop their punitive PP rules they added last decade.

Only my thoughts, but I don't have concerns for the leccy sector next decade, I'm confident that RE additions can outpace the move to leccy from transport, heating etc, and the further ageing out of the older nuclear. So long as folk understand that a significant percentage of demand may be met by FF gas at times, but that it won't add up to too much on an annual basis, then we'll have the foundations to perfect things. Leading to ...

.... @CW, been thinking about that longer term storage issue, and wondering how much the UK may be protected given our potential for vast over production and export of RE from off-shore wind? Overcapacity does muck up prices and can push them negative, but with enough interconnectors, and assuming the rest of Europe want the leccy(?), then that's the first step. Just to be clear, I mean that in all the reports and scenarios for high RE penetration, overcapacity always shows up as stage one, before moving to longer/larger term storage.


Just to sway, I'll try to find post news/info on RE progress going forward, but 2020's good increase is flattered by reduced demand during Covid, and 2021 was hit hard by a bad wind year, and the demand bounce back from Covid, so the steady annual growth of RE was distorted, but hopefully this year will show us better where we are / heading?

gefnew

This is quite a large farm if it gets through.
https://www.bbc.co.uk/news/uk-england-humber-63075165

Exiled_Tyke

gefnew said:

This is quite a large farm if it gets through.
https://www.bbc.co.uk/news/uk-england-humber-63075165

Fantastic that they see the need to consult with the local community but it does worry me what ill-informed views may then start spreading (some of which sadly have previously been shared on these boards) .  I hope they've got a good PR team together.  

Coastalwatch

Exiled_Tyke said:

gefnew said:

This is quite a large farm if it gets through.
https://www.bbc.co.uk/news/uk-england-humber-63075165

Fantastic that they see the need to consult with the local community but it does worry me what ill-informed views may then start spreading (some of which sadly have previously been shared on these boards) .  I hope they've got a good PR team together.  

Agree whole heartedly with you there ET. Simply the term agricultural land will cause a huge reaction by many. And yet, as has been discussed in the media recently, if it is no better than subclass 3b -(moderate quality agricultural land with strong limitations that affect the choice of crop, timing and type of cultivation/harvesting or level of yield. This land produces moderate yields of a narrow range of crops, low yields of a wide range of crops and high yields of grass) then planning should not be declined purely on the basis that it is "Agricultural Land". 

I wonder if they are assuming that simply because of it's location, close to Drax Power station, that none of the locals would be particularly concerned given what they have already had to contend with this last half century or so! Either way good luck to them we certainly need all the renewable generation we can rustle up. When compared with the likes of Drax, be it coal or biomass, then solar is possibly just a minor irritation.

Unusually these days I can see no mention of battery stiorage which makes for an ideal companion!

 

ABrass

The article said they were planning to let sheep graze around the panels. Which is nice.