Green, ethical, energy issues in the news

pile-o-stone

I’m not sure if we are using this thread to post Green & Ethical news anymore, but I found the article below in TreeHugger quite interesting

https://www.treehugger.com/energy-efficiency/energy-subway-tunnels-could-heat-and-cool-thousands-homes.html

“Margaux Peltier, whose masters thesis is the basis for the study, calculates that if they line half the new Lausanne M3 subway with heat recovery pipes, they can heat 1500 standard 800 SF apartments, "or as many as 4,000 Minergie-certified energy-efficient units." Minergie is sort of a Swiss version of Passivhaus. “Switching from gas-fired heating would cut the city’s CO2 emissions by two million tons per year,” adds Peltier.”

GreatApe

1961Nick wrote: »

The point that's being made is not that you "don't respect GA's opinions", it's that you don't seem to respect GA's right to have an opinion. Constantly promoting the fact that you have chosen to ignore GA, & then encouraging others not to quote him, is blatant use of your influence for censorship purposes.

He is a bully and has tried this for a long time with some success by which I mean he has convinced one or two of his mates to our me on ignore even though they seem to somehow know most of what I post.

I've read many of GA's posts & to tarnish him as anti-RE is nonsense. It's clear that he is pro-RE, but his argument is that wind & solar has reached saturation point & the grid doesn't currently need any more.
.

I'm glad one person seems to have understood that point which I make over and over again but few listen to

The UK grid is soon saturated with non fossil fuels so I say the UK doesn't need any significant deployment of additional PV or Wind or Nuclear or tidal, beyond what already exists, what is under construction and what is committed to

With the grid solved move onto heating which is a much more difficult task

GreatApe

Martyn1981 wrote: »

An example that is both anti-RE and ridiculous. Thank you.

Even the National grid own projections show the UK grid going towards 85% green before 2025 and it stays around that 85% mark until 2030 even though more wind and solar will be deployed that is because a lot of that additional solar wind just displaces clean imports. Beyond about 85% it's very hard to achieve because an additional solar panel mostly outputs when there is too much solar and an additional wind produces very little output when the existing wind fleet produces very little output

I'm not against investment but what makes more sense is interconnectors at this stage.

Why spend $1 billion on solar wind if 85% of it is curtailing existing domestic or foreign clean output why not spend $1 billion on an interconntor which can actually help fill in the gaps?

PS - As you recently tried out a version of the 'CO2 is plant food' anti-AGW argument, I thought you might like this recent interview with an ex USDA whistleblower discussing the publication blocking of his peer reviewed paper on the reduction of nutrional value in rice due to AGW.

U.N. Warns Climate Change Could Trigger Global Food Crisis | Velshi & Ruhle | MSNBC

More nonsense like your coal costing the NHS £6 billion a year were is this £6 billion saving now that coal burning is down 90% ???

GreatApe

1961Nick wrote: »

Is that even possible without massive expenditure on transmission infrastructure that might only ever be needed once in a blue moon.

Should be

They just need the circuits to cut out more specific parts of the network

However I do wonder about how vulnerable the grid is as it gets smarter

For a short period I thought it would be a good idea for appliances to get smart to do some level of load management. Maybe shifting fridges or hot water tanks to consume at different times of the day. However you then introduced the possibility of some kid or some hacker gaining the ability to turn on off tens of millions of devises at the same instant possibly knocking out the grid or causing significant problems

Maybe a slightly less efficient dumb grid is better than a slightly more efficient smart grid that is vulnerable to hackers. Electricity is a huge economic multiplier. Having it down for even minutes causes huge losses for business

markin

How cheap storage would have to get for renewables to get to 100 percent, Out of an MIT lab run by researcher Jessika Trancik.

To spoil the ending: The answer is $20 per kilowatt hour in energy capacity costs. That’s how cheap storage would have to get for renewables to get to 100 percent. That’s around a 90 percent drop from today’s costs. While that is entirely within the realm of the possible, there is wide disagreement over when it might happen; few expect it by 2030.

A cost-optimal wind-solar mix with storage reaches cost-competitiveness with a nuclear fission plant providing baseload electricity at a cost of $0.075/kWh at an energy storage capacity cost of $10-20/kWh. To reach cost- competitiveness with a peaker natural gas plant at $0.077/kWh, energy storage capacity costs must instead fall below $5/kWh (at a storage power capacity cost of $1,000/kW). To provide baseload, intermediate, bipeaker, and peaker electricity at $0.10/kWh with an optimal wind-solar mix, energy storage capacity costs must reach approximately $30–70/kWh, $30v90/kWh, $10–30/kWh, and $10–30/kWh respectively.

https://www.vox.com/energy-and-environment/2019/8/9/20767886/renewable-energy-storage-cost-electricity

Highlights

• •Model of renewables with storage in 4 locations over 20 years with hourly resolution
• •Electricity costs respond more to costs of storage energy capacity than power capacity
• •Energy storage capacity below $20/kWh could enable cost-competitive baseload power
• •Meeting demand with other sources during 5% of hours can halve electricity costs

Context & Scale

Wind and solar energy can produce decarbonized electricity, but to reliably meet demand these intermittent resources require other technologies such as energy storage, supplemental generation, demand management, and transmission expansion. Many studies estimate the costs of supplying electricity with renewables for particular storage cost assumptions.
Here we study which characteristics most impact renewable electricity costs, including cost features of proposed storage technologies. Considering 20 years of resource fluctuations, we capture large, infrequent events affecting storage requirements. We estimate that cost-competitively meeting baseload demand 100% of the time requires storage energy capacity costs below $20/kWh. If other sources meet demand 5% of the time, electricity costs fall and the energy capacity cost target rises to $150/kWh. The results can inform policy and investments in technology research, development, and deployment.


Summary

Deeply decarbonizing electricity production will likely require that low-carbon sources meet energy demand throughout days, years, and decades. Wind and solar energy are possible low-carbon options, but resource variability can limit their reliability. Storage can help address this challenge by shaping intermittent resources into desired output profiles. But can solar and wind energy with storage cost-competitively fulfill this role? How do diverse storage technologies compare? We address these questions by analyzing systems that combine wind and solar energy with storage to meet various demand profiles. We estimate that energy storage capacity costs below a roughly $20/kWh target would allow a wind-solar mix to provide cost-competitive baseload electricity in resource-abundant locations such as Texas and Arizona. Relaxing reliability constraints by allowing for a few percent of downtime hours raises storage cost targets considerably, but would require supplemental technologies. Finally, we discuss storage technologies that could reach the estimated cost targets.

Full paper
https://www.cell.com/joule/fulltext/S2542-4351(19)30300-9

Martyn1981

markin wrote: »

How cheap storage would have to get for renewables to get to 100 percent, Out of an MIT lab run by researcher Jessika Trancik.

Thanks, that's an excellent article. I think they set out the issues well, and the challenge of reaching 100% from clean energy only. No idea if $20/kWh (down from $200) is correct (well out of my comfort zone), but all my concerns were quickly answered:

What about bio-energy, this is after the US?

Another faction believes that renewables will ultimately fall short and need assistance from nuclear power and natural gas or biomass with carbon capture and storage.

Are there alternatives to localised storage?

Second, remember, the team is modeling a system in which storage is doing almost all the flexibility work. In fact, there are other sources of grid flexibility. My favorite candidate for flexibility dark horse is “load flexibility,” demand-side programs that can shift energy consumption around in time. Another source of flexibility is enhanced long-distance transmission, to carry renewable energy from regions that produce it to regions that need it. Another is dispatchable renewables like run-of-the-river hydro and advanced geothermal.

All of those sources of flexibility will grow and help to smooth out renewables. Storage won’t have to do all the work on its own. That, too, should ease the price pressure.

Why does RE generation have to match consumption, aren't we assuming(?) some overcapacity as a cheap 'storage' option?

All of those sources of flexibility will grow and help to smooth out renewables. Storage won’t have to do all the work on its own. That, too, should ease the price pressure.

Third, a renewables+storage system also gets easier if renewables get cheaper. The numbers that Trancik’s team use for renewables are quite conservative. (For instance, $1/Watt solar costs are already being beat routinely in the US.) If renewable energy continues to defy expectations and plunge in cost, it would become cheaper and easier to oversize renewables and curtail the excess energy. That in turn would ease pressure on storage.

Why 100%?

In short, the headline $20/kWh cost target for energy storage is almost certainly more stringent than what will be required in the real world. Even the $150/kWh target required for an EAF of 95 percent is likely too stringent. In the real world, storage will be assisted by other forms of grid flexibility like long-distance transmission, load flexibility, and microgrids, along with regulatory and legislative reforms. And renewables will probably continue to get cheaper faster than anyone predicts.

So let’s call the target $150-$200, or thereabouts. Can storage hit that?

So for now, a softer future target of 95%, at a 'too stringent $150/kWh', looks doable at todays storage costs and options. Excellent news.


Note - I thought those storage costs per kWh seemed too high as domestic options are already well below that, but the article explains that they are talking about the cost of buying and installing a kWh of storage, not the cost of using a kWh.

For instance one flow battery supplier is contracting $95/KWh for 2022 delivery on massive batts, which would, fairly I assume, come in at around $200/kWh delivered, installed and all other costs, but at 5,000+ cycles, would work out at a cost of ~4c/kWh.


Good news, there are loads of generation + storage contracts being issued in the US at very, very low prices. I've posted some, and on one occasion the price was so, so cheap, that I 'naturally' misread it as 10x higher till Z pointed out my mistake.

Most of the contracts require storage of about 4hrs, since obviousluy, the majority of the generation/supply doesn't need any storage, so storage costs only add to the small proportion that needs, well, storage, and those cost are diluted across the far larger volume of energy supplied.

All looking good. Nice start to the week.

Martyn1981

pile-o-stone wrote: »

I’m not sure if we are using this thread to post Green & Ethical news anymore, but I found the article below in TreeHugger quite interesting

https://www.treehugger.com/energy-efficiency/energy-subway-tunnels-could-heat-and-cool-thousands-homes.html

“Margaux Peltier, whose masters thesis is the basis for the study, calculates that if they line half the new Lausanne M3 subway with heat recovery pipes, they can heat 1500 standard 800 SF apartments, "or as many as 4,000 Minergie-certified energy-efficient units." Minergie is sort of a Swiss version of Passivhaus. “Switching from gas-fired heating would cut the city’s CO2 emissions by two million tons per year,” adds Peltier.”

Rushing (have to run) so sorry if this is mentioned, but I seem to recall that Sweden uses waste heat like this to heat buildings close to underground stations.

I saw the London Underground was mentioned, and there have been large competition rewards offered for solutions to cool the network now that they have almost completely dried out, leading to an end to the evaporative cooling.

Martyn1981

Martyn1981 wrote: »

Hopefully a news item to follow, but looks like wind was supplying 50% of demand during part of Friday night / Saturday morning.

Obviously demand at night is lower, so wind %'s will rise, but records keep falling, which is a nice thing.

No update yet, but also looking out now for articles on Germany, which may have gone 100% RE for short periods last weekend.

JKenH

Martyn1981 wrote: »

No update yet, but also looking out now for articles on Germany, which may have gone 100% RE for short periods last weekend.

To some what I am about to ask might appear a stupid question and has no particular pro or anti RE stance as the same question would apply to FF as well.

What actually happens to the excess power when more is generated than is being consumed? I asked this on a FF power station tour a few years back but the tour guide didn’t understand my question. I was thinking that energy has been generated and if it is not being used then presumably it has to go somewhere.

Am I correct in thinking that the grid voltage or frequency will rise up to a certain limit - but if there is still too much power and the generator can’t be shut down quickly where does that power go?

With the National Grid in place presumably power can be moved around so there isn’t an excess condition in anyone place and the situation should be avoided but in the very short term can a situation arise where there is just too much power for the grid - is there a way to just dump this power to earth?

mmmmikey

JKenH wrote: »

What actually happens to the excess power when more is generated than is being consumed?

The simple answer is that (a) generators are controlled so this doesn't happen very often, and (b) the National Grid has contracts in place to pay people to use the spare power - i.e. you occasionally see negative pricing on the wholesale market, you get paid to use it.

With FF generators this isn't really a problem as long as you operate within the output range of the generator. It's a bit like a car travelling at a constant 70mph on the motorway. If you start to go down a hill, you feather the throttle to keep the speed constant and use less fuel. On a very steep downhill, you may need to change down a gear to stop the car running away as there's only so far you can throttle back without the engine cutting out, but this doesn't happen suddenly and you have time to react. In the same way, with FF you can "ease off the throttle" by burning less fuel but you get to the point with generators where you have to switch one off. So spare power isn't something that happens very often at the moment - generators adjust themselves to cope.

With wind it's a bit more complicated - you have to regulate the power by slowing down the turbine some way or using a "dump load" to soak up any excess.

But sometimes things go wrong and you have spare power, for example if a large user suddenly fails. Just as your car engine would start to race if you didn't adjust the throttle when you started to go down hill, generators start to spin more quickly when there's less load, so the frequency increases. This means that by monitoring the grid frequency, big power users such as refridgeration plants, aluminimum smelting plants, etc. can change their usage to help keep things in balance. National Grid pay them to do this through the "frequency response" market. This works in two directions - they can increase use when there is spare power (inidcated by increasing frequency) and decrease use when there isn't enough (indicated by falling frquency as the generators slow down under load).

Hope this makes sense