The Death Of Fossil Fuels

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Bird on a Fire
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Re: The Death Of Fossil Fuels

Post by Bird on a Fire » Wed Aug 25, 2021 12:16 pm

One area of renewable tech I've been hearing about "in development" for years, with little apparent progress in terms of at-scale installations, is wave energy tech.

So I'm pleased to see a prototype unit will be installed for field testing this year in Portugal. As the amount of wind generation illustrates (though it's mostly onshore, I think), not to mention all those tourists who come here for surfing and paragliding, Portugal has a very windy, wavy coast. https://www.theportugalnews.com/news/20 ... letter-595
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Re: The Death Of Fossil Fuels

Post by Grumble » Wed Aug 25, 2021 8:01 pm

Bird on a Fire wrote:
Wed Aug 25, 2021 12:16 pm
One area of renewable tech I've been hearing about "in development" for years, with little apparent progress in terms of at-scale installations, is wave energy tech.

So I'm pleased to see a prototype unit will be installed for field testing this year in Portugal. As the amount of wind generation illustrates (though it's mostly onshore, I think), not to mention all those tourists who come here for surfing and paragliding, Portugal has a very windy, wavy coast. https://www.theportugalnews.com/news/20 ... letter-595
I slightly struggle with wave energy, isn’t it basically the same thing as wind energy? Why have a wave generator rather than a wind turbine?
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Re: The Death Of Fossil Fuels

Post by dyqik » Wed Aug 25, 2021 8:17 pm

Grumble wrote:
Wed Aug 25, 2021 8:01 pm
Bird on a Fire wrote:
Wed Aug 25, 2021 12:16 pm
One area of renewable tech I've been hearing about "in development" for years, with little apparent progress in terms of at-scale installations, is wave energy tech.

So I'm pleased to see a prototype unit will be installed for field testing this year in Portugal. As the amount of wind generation illustrates (though it's mostly onshore, I think), not to mention all those tourists who come here for surfing and paragliding, Portugal has a very windy, wavy coast. https://www.theportugalnews.com/news/20 ... letter-595
I slightly struggle with wave energy, isn’t it basically the same thing as wind energy? Why have a wave generator rather than a wind turbine?
Waves pick up energy from the wind and tides across large areas, and then travel to your generator. The power density in waves may be higher, although I'm not sure about that.

And people already build structures to block waves, so you can do them a favour by using that power rather than it dissipating on their structures.

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Re: The Death Of Fossil Fuels

Post by Bird on a Fire » Wed Aug 25, 2021 8:22 pm

Water is denser than air, so you can get more energy from a given area/volume. (Handwavy physics alert!)

Waves are also partly caused by tidal movements, making them more predictable and available when it isn't so windy.

So again they might be quite useful as part of a baseline (if they work, can be produced cheaply at scale etc etc).
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Re: The Death Of Fossil Fuels

Post by monkey » Wed Aug 25, 2021 8:34 pm

Bird on a Fire wrote:
Wed Aug 25, 2021 12:16 pm
One area of renewable tech I've been hearing about "in development" for years, with little apparent progress in terms of at-scale installations, is wave energy tech.

So I'm pleased to see a prototype unit will be installed for field testing this year in Portugal. As the amount of wind generation illustrates (though it's mostly onshore, I think), not to mention all those tourists who come here for surfing and paragliding, Portugal has a very windy, wavy coast. https://www.theportugalnews.com/news/20 ... letter-595
Portugal's already had one "commercial sized" wave farm. It lasted 2 months - clicky

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Re: The Death Of Fossil Fuels

Post by monkey » Wed Aug 25, 2021 8:35 pm

Grumble wrote:
Wed Aug 25, 2021 8:01 pm
Bird on a Fire wrote:
Wed Aug 25, 2021 12:16 pm
One area of renewable tech I've been hearing about "in development" for years, with little apparent progress in terms of at-scale installations, is wave energy tech.

So I'm pleased to see a prototype unit will be installed for field testing this year in Portugal. As the amount of wind generation illustrates (though it's mostly onshore, I think), not to mention all those tourists who come here for surfing and paragliding, Portugal has a very windy, wavy coast. https://www.theportugalnews.com/news/20 ... letter-595
I slightly struggle with wave energy, isn’t it basically the same thing as wind energy? Why have a wave generator rather than a wind turbine?
You might be able to put a wave farm in a place you can't put a windfarm.

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Re: The Death Of Fossil Fuels

Post by Bird on a Fire » Wed Aug 25, 2021 9:00 pm

monkey wrote:
Wed Aug 25, 2021 8:34 pm
Bird on a Fire wrote:
Wed Aug 25, 2021 12:16 pm
One area of renewable tech I've been hearing about "in development" for years, with little apparent progress in terms of at-scale installations, is wave energy tech.

So I'm pleased to see a prototype unit will be installed for field testing this year in Portugal. As the amount of wind generation illustrates (though it's mostly onshore, I think), not to mention all those tourists who come here for surfing and paragliding, Portugal has a very windy, wavy coast. https://www.theportugalnews.com/news/20 ... letter-595
Portugal's already had one "commercial sized" wave farm. It lasted 2 months - clicky
Yikes. Sounds like a combination of technical issues and bad management.
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Re: The Death Of Fossil Fuels

Post by dyqik » Wed Aug 25, 2021 9:28 pm

Bird on a Fire wrote:
Wed Aug 25, 2021 8:22 pm
Water is denser than air, so you can get more energy from a given area/volume. (Handwavy physics alert!)
Because waves are surface phenomena, I wasn't sure how the height of wind turbines vs waves balanced this out per surface area occupied. O course, wave power generators tend to be strung out in lines vs fields of wind turbines.
Bird on a Fire wrote:
Wed Aug 25, 2021 8:22 pm
Waves are also partly caused by tidal movements, making them more predictable and available when it isn't so windy.
The first bit of my reply was aimed at saying that wind over a wide area generates waves that travel to the wave generator - this means it's effectively averaging over a larger area, and so less likely to be calm (pretty obvious thing that happens if you've spent much time at the beach - the air can be pretty still while there are large waves).

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Re: The Death Of Fossil Fuels

Post by monkey » Wed Aug 25, 2021 10:45 pm

Bird on a Fire wrote:
Wed Aug 25, 2021 9:00 pm
monkey wrote:
Wed Aug 25, 2021 8:34 pm
Bird on a Fire wrote:
Wed Aug 25, 2021 12:16 pm
One area of renewable tech I've been hearing about "in development" for years, with little apparent progress in terms of at-scale installations, is wave energy tech.

So I'm pleased to see a prototype unit will be installed for field testing this year in Portugal. As the amount of wind generation illustrates (though it's mostly onshore, I think), not to mention all those tourists who come here for surfing and paragliding, Portugal has a very windy, wavy coast. https://www.theportugalnews.com/news/20 ... letter-595
Portugal's already had one "commercial sized" wave farm. It lasted 2 months - clicky
Yikes. Sounds like a combination of technical issues and bad management.
Given it was 2008 and the wiki said that the owners were in administration, I wouldn't be surprised if Moneygeddon had something to do with it.

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Re: The Death Of Fossil Fuels

Post by Bird on a Fire » Wed Aug 25, 2021 10:46 pm

The averaging/concentrating effect of waves makes sense. I know they design wind turbine fields to try to maximise extraction of energy from the air, but I guess a line of wave energy converters is already benefiting from the same kind of effect occurring naturally. (The wiki page for WEC does confirm my hazy recollection that energy density is higher).

And yes, spending a lot of time at tidal beaches in the east Atlantic really rams home the amount of power available there, and you can pretty much set your clock by it. That kind of dependability must count for something, compared to the capricious winds and often-coy sun.
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Re: The Death Of Fossil Fuels

Post by Bird on a Fire » Wed Aug 25, 2021 10:54 pm

monkey wrote:
Wed Aug 25, 2021 10:45 pm
Bird on a Fire" wrote:
Wed Aug 25, 2021 9:00 pm
monkey wrote:
Wed Aug 25, 2021 8:34 pm


Portugal's already had one "commercial sized" wave farm. It lasted 2 months - clicky
Yikes. Sounds like a combination of technical issues and bad management.
Given it was 2008 and the wiki said that the owners were in administration, I wouldn't be surprised if Moneygeddon had something to do with it.
Ah yeah, I'd forgotten about all that malarkey.

I started visiting the Tagus estuary regularly in 2009, when the crash was really hitting hard. Loads of house-building projects were abandoned (many have only just been finished; others in less desirable areas, like the one across the street from me, are still unfinished, towering above the city skyline with nobody at home). Everyone lost their jobs and were suddenly just wandering around the mudflats at low tide, trying to find shellfish to eat or worms to use as bait. It was pretty grim.

So there would have been zero local capital available, and even slower and less helpful bureaucracy than usual. (Which is saying something - much as I love living there, I wouldn't volunteer to run a business in Portugal.)

Plus loads of infrastructure projects get abandoned anyway. There are half-finished motorways scrubbing over next to gravel tracks, plans for high-speed rail gathering dust, etc. Corruption, mismanagement and lack of capital are all endemic. It's like a bit of Latin America somehow got stuck on the wrong side of the Atlantic.
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Re: The Death Of Fossil Fuels

Post by IvanV » Wed Aug 25, 2021 10:58 pm

Bird on a Fire wrote:
Tue Aug 24, 2021 3:41 pm
What's the worst case scenario with wind - say, what's the week where it was performing at the lowest % of capacity?
A couple of years ago I analysed wind data from 2011-2019, and answered a similar question, for my own entertainment.

So in 2011-2019 there were 3 occasions when wind capacity factor was below 12.5% in every 5 minute period for a total of 7 consecutive days. The longest such period in that 8 year dataset was 9 days. That's doesn't mean that the capacity factor for the week was below 12.5%, it means it was below 12.5% continuously for a week. So probably over such a week, capacity factor was more like say 7.5%. That's what I chose to calculate on that occasion, I suppose I could go back and try to reanalyse the data to assess the specific question you asked, what is the week with the lowest capacity factor averaged over the week. It is a sufficiently large dataset you have to be a little canny to do this in Excel in an efficient way. I just looked at the formulas again, and I must have had to think a bit over them, they aren't super-obvious.

Probably a better calculation to do would be something like, how far short of average can it be over a week, a fortnight, a month, over 2 months, etc. That would probably be more useful for the question you are asking.

However there is a big wrinkle in such an estimate, which is not all wind output is measured and you can get data at 5 mins, or even daily, only so-called "operationally metered" wind. Operationally metered wind is about 80% of total wind, though in fact it varies from day to day rather more than you'd expect. And it has also varied over the years. That's because all that off-shore wind in the north sea is operationally metered, and unmetered wind is smaller wind farms (under say 100MW) which are preferentially in the west of the country and in Scotland. So they get a materially different wind experience. Such wind is treated as negative consumption rather than generation. You can get hold of data enabling short-term esimates of the proportion of wind that is unmetered, but gathering and using that was a lot of work and processing, so I didn't. You can get taht data on the National Grid ESO website, but it's not precisely just what you'd want and takes a bit of finding. So as I wasn't being paid for this, I just assumed it was 80%.

If you would like to do similar calculations, then my source of instaneous output of operationally metered wind is gridwatch.co.uk. A nice trick you can do on this site is to choose the tab that says "Meters" as opposed to "Bars". And when you get there, you can reorder the meters by dragging them around. If you drag the Wind meter (blue) to the top-left-most point it will go, which is just to the right of "Carbon Neutral", then it will be at the bottom in graphs below, and you can see very visibly the pattern of wind production. It has a distinct tendency to alternate between windy patchs and unwindy patches. This year, there was an extended low wind period of over 3 weeks starting on 9 April.

Now you need to compare wind output with a database of wind capacity. That's National Statistics/BEIS data, table ET 6.1. It's quarterly, not every 5 mins.

Here's the kind of simple calculation you can make. So, what's the average capacity factor of wind over the year? Actually it varies surprisingly from year to year. In a windy year it can be almost 30%, in a less windy year it can rather nearer 25%. So let's take 25% to be safe. So in a period when average wind capacity is running at 12.5% for a whole week, we have a shortfall of half our wind output for the week, that we'll have to get from somewhere else. What's he average ouput of total electricity? Usually somehting like 30GW, but it was rather lower in 2020 because of lockdowns. So you can start working out how many GWdays you need to have on hand to fill in gaps of lack of output in different scenarios. I think it is useful to do back of the envelope esimates like this just to get a feeling for it. It's very basic arithmetic, though the data handling is rather harder.

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Re: The Death Of Fossil Fuels

Post by Bird on a Fire » Wed Aug 25, 2021 11:19 pm

Thanks Ivan - that's exactly the kind of figure I was hoping for. It sounds like modestly overbuilding capacity wouldn't be enough without also having storage that can even out supply over months. You could build 1000% capacity or something, but the UK isn't even at 25% of demand yet.
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Re: The Death Of Fossil Fuels

Post by Woodchopper » Thu Aug 26, 2021 7:48 am

What happens in Denmark and Norway which relay to varying degrees on mostly wind and mostly hydro power is big monthly changes in price.

Here's electricity prices in Norway:
NO per kwh.jpg
NO per kwh.jpg (78.89 KiB) Viewed 403 times
There is a roughly twentyfold difference between the highest and lowest price.

Similarly in Denmark here's the spot price which can be paid by consumers if they choose:
Spot DK.jpg
Spot DK.jpg (166.67 KiB) Viewed 403 times
And what I assume is a smoothed price for other consumers who prefer more predictability:
Termin DK.jpg
Termin DK.jpg (140.52 KiB) Viewed 403 times
Source> https://www.energidanmark.dk/markedsinfo/

Even then we are looking at electricity prices having doubled in the space of ten months. Of course the price can go down.

The price changes are a form of demand management. The price goes up and people use less - eg turning down the thermostat in the winter. So they are an important component of dealing with variations in supply.

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Re: The Death Of Fossil Fuels

Post by FlammableFlower » Thu Aug 26, 2021 8:16 am

On tidal - there are quite a few projects in the testing phase being deployed in and around Scapa Flow - but that is a fairly obvious place to go as it has reliable strong currents, so it might not be so good for comparing to how things will fare in the "real world".

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Re: The Death Of Fossil Fuels

Post by dyqik » Thu Aug 26, 2021 3:31 pm

FlammableFlower wrote:
Thu Aug 26, 2021 8:16 am
On tidal - there are quite a few projects in the testing phase being deployed in and around Scapa Flow - but that is a fairly obvious place to go as it has reliable strong currents, so it might not be so good for comparing to how things will fare in the "real world".
There are several good options around the UK though, so it should absolutely be in the mix there. I suspect the strong currents may be more of a hindrance than a help, as it means everything has to be that much stronger.

And the time delays to tides around the UK means that it's not ever going to completely go to zero output.

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Re: The Death Of Fossil Fuels

Post by monkey » Thu Aug 26, 2021 4:19 pm

dyqik wrote:
Thu Aug 26, 2021 3:31 pm
There are several good options around the UK though, so it should absolutely be in the mix there. I suspect the strong currents may be more of a hindrance than a help, as it means everything has to be that much stronger.
Wouldn't that depend on the type of tidal power? A turbine thingy working off of the kinetic energy would be best with a strong current, but a barrage depends on change of water level, which could be large with a relatively low current.
dyqik wrote:
Thu Aug 26, 2021 3:31 pm
And the time delays to tides around the UK means that it's not ever going to completely go to zero output.
Yeah, but the minimum is going to still be much lower than the peak. A mix of turbine thingy and barrages would smooth stuff out, cos the barrage would work out of phase with the tide.

I think one of the big advantages to tidal would be how predictable the times you get power out of it will be.

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Re: The Death Of Fossil Fuels

Post by Bird on a Fire » Fri Sep 03, 2021 12:14 pm

Iraq is trying to urge OPEC states to move into the 21st century https://www.theguardian.com/environment ... ble-energy

Ali Allawi's (Iraq's finance minister) Graun article is pretty good. One of the big challenges in killing off fossil fuels is supporting fossil-dependent economies in transitioning to sustainability, rather than just expecting them to take a huge economic hit. (Obviously it would have been better if they'd already diversified, but we can't change the past.)
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Re: The Death Of Fossil Fuels

Post by FlammableFlower » Mon Sep 13, 2021 1:05 pm

Report on a trial of blending 20% hydrogen into gas supply: [urlhttps://hydeploy.co.uk/app/uploads/2018/02/21063_HyDeploy_Carbon_Savings_Report1_DIGITAL.pdf]HyDeploy Carbon_
Savings Report[/url]

Commentary on it

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Re: The Death Of Fossil Fuels

Post by bjn » Mon Sep 13, 2021 1:38 pm

From what I understand, you aren't going to be able to distribute more than 20% H2 by volume in our current pipework, which is only ~8% of energy in the gas due to hydrogen's low density. You either have to increase the pressure or increase the diameter of the pipes to get more H2 in there. If increasing the proportion of H2, you also have fiddle with burners etc... at the domestic end. Plus the increased danger of gas explosions, as H2 goes boom much easier than CH4, plus it's waaaay more leaky.

You are better off electrifying most uses of CH4, eg: heat pumps for heating, and dumping the electricity straight into that. Modern heat pumps have COPs over 3 (ie: 3X the heat energy comes out as you put in as electricity), add in inefficiencies in cracking water and burning it, you get something like 6X 4X the heat from a heat pump for the same electricity as if you used to crack H2 piped to your boiler. Plus a heat pump can cool you down in summer. It's stupid to use H2 for domestic heating.

Seasonal storage maybe, the split H2 just gets stored nearby and used to generate electricity as needed to smooth out longer term fluctuations. Electricity is great stuff, fungible and able to use a range of sources and be used for a range of things. Gas ain't so flexible.

Regardless, the first thing that should be done is to insulate the hell out of the UK's housing stock. Stonking subsidies for that, which would also inject money into the economy at a nice level.

ETA: fixed 4x and adding a link to BNEF's demand side analysis for the use of H2.

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Re: The Death Of Fossil Fuels

Post by lpm » Mon Sep 13, 2021 2:21 pm

bjn wrote:
Mon Sep 13, 2021 1:38 pm
Regardless, the first thing that should be done is to insulate the hell out of the UK's housing stock.
These single-issue protesters are doing just that. Not only did their actions insulate a bunch of homes, they also made themselves remarkably popular with the general public. Win win.

https://www.bbc.co.uk/news/uk-england-b ... s-58543603
What ever happened to that Trump guy, you know, the one who was president for a bit?

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Re: The Death Of Fossil Fuels

Post by bjn » Mon Sep 13, 2021 3:59 pm

lpm wrote:
Mon Sep 13, 2021 2:21 pm
bjn wrote:
Mon Sep 13, 2021 1:38 pm
Regardless, the first thing that should be done is to insulate the hell out of the UK's housing stock.
These single-issue protesters are doing just that. Not only did their actions insulate a bunch of homes, they also made themselves remarkably popular with the general public. Win win.

https://www.bbc.co.uk/news/uk-england-b ... s-58543603
How many people did they alienate as opposed to recruiting? Many of the 'bl..dy protesters!' types wouldn't care anyway, so are already alienated. How many people will now know of this because of the coverage given to the protest and go, "That's a bl..dy good idea!", even if they think the protesters are somewhat tossers?

No idea. But your implied premise that they alienate more people from their cause than recruit needs more evidence.

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Re: The Death Of Fossil Fuels

Post by Bird on a Fire » Mon Sep 13, 2021 4:43 pm

Anybody more concerned about some disrupted traffic than the climate emergency is a dinosaur who ought to be ignored or mocked openly.

The only problem with that protest is that it needs to be bigger, say on the scale of a renters' strike until decent efficiency standards are mandated. Hit the wealthy in their pockets and they'll sort it out faster than just annoying a bunch of drivers on the M25.
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Re: The Death Of Fossil Fuels

Post by jimbob » Tue Sep 14, 2021 9:12 am

FlammableFlower wrote:
Mon Sep 13, 2021 1:05 pm
Report on a trial of blending 20% hydrogen into gas supply: [urlhttps://hydeploy.co.uk/app/uploads/2018/02/21063_HyDeploy_Carbon_Savings_Report1_DIGITAL.pdf]HyDeploy Carbon_
Savings Report[/url]

Commentary on it
Nice
Have you considered stupidity as an explanation

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Re: The Death Of Fossil Fuels

Post by lpm » Wed Sep 15, 2021 8:00 am

Yet more disruption to traffic. Incredibly unpopular.
Completely unacceptable disruption to hard-working people's lives here. If nature wants people to care more about it, this is totally the wrong way of going about things. I even understand there are *much* more disruptive actions planned. Disgusting!
https://twitter.com/jamzbrux/status/1437793811422498824
What ever happened to that Trump guy, you know, the one who was president for a bit?

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