A simple challenge 5

[GregLocock]

Rough out a fossil fuel free system for a given populated area to replace a 1 GW coal power station, at 2020-2022 prices. use 1 year of hour by hour weather observations

Rules

maximum of 1 month per year scheduled downtime

1 hour per year unscheduled dark due to lack of storage.

No extension leads.

No hydro using naturally occurring sites for both basins (they're already in use)

30 year design life.


I'm selecting a local power station, now gone, in Anglesea Victoria. It has fairly good windpower prospects, including offshore. I'm using the weather observations from a town just along the coast called Airey's Inlet, or Hairy Singlet.

http://www.bom.gov.au/products/IDV60801/IDV60801.94846.shtml

Cheers

Greg Locock


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[GregLocock]

Shrugs, not my place to say. But I'd have thought a bit more analysis and a bit less unicorn chasing would probably be a better use of time.

Cheers

Greg Locock


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All the analysis in the world won't fix the mess, which ultimately is not a set of technical problems. But to think the only other way is chasing unicorns is not only a false either/or proposition, it demonstrates how ingrained is our impulse to think only in terms of technological solutions.

Engineers are like doctors who believe the cure for poisoning is administering more poison, and that is on full display in these threads.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[LionelHutz]

Looking at the data for the area I live in, 1GW of coal (assuming good uptime for that coal station) would likely require about 3GW of wind turbine or about 5MW of solar panels. That's probably something like 2500 wind towers which isn't impossible to do but becomes rather silly when you scale that to the national energy use levels. Storage would have to be what, around 150GWh? I have no idea how that kind of energy could actually be practically stored, but no-one else does either. Not much point trying to decide on the exact distribution of any of it.

I don't know what you mean by 1 month per year of scheduled downtime, but distributed RE systems should never be all offline at once. Maybe you meant for example that each wind tower would be offline for a month per year. It may be better to say 10% of the RE generation would be offline at any one time?

 

[GregLocock]

The German wind industry reckons that 1 GW of demand can be satisfied by 6 GW of land based wind, on average over the year, without extra storage. The intermittency problem takes it up by another 50% , but can't deal with wind droughts. They reckon they need 80% backup from non wind sources. This is taken from a 2004 report by a big wind operator

http://docs.wind-watch.org/EonWindReport2004.pdf

. it is old data so they'd have been using smaller turbines, OTOH presumably they'd have been in the best locations. Extracts from a later report suggest that 25 GW of wind is needed to replace 1 GW of coal, as more wind is installed, but I haven't been able to get hold of the original. <Late edit, yes I have but it is on Scribd so I ain't going there

https://www.scribd.com/document/49853853/EON-2005-Report-1>

From my own experience in SE Australia on average over the year a solar panel produces about 4 hours of rated power a day (1700 kWh per year from a 1 kW panel), ie again you need at least 6 GW of panels to replace 1 GW of demand over the years, again ignoring the intermittency/storage/ solar drought issues). With solar the general form of the insolation curve is predictable over the year for a given location, but that masks the effect of cloud cover, which can easily result in a week of perhaps 1/2 hour rated power per day. Of course in the deserts this is not such a big deal, but then you need 1000 km interconnects.

Anyway I'm slowly making progress with the UK data, the hard bit as usual is turning weird time stamp formats into engineering units. The other trickier bit is figuring out which of the reported channels are generation, and which are just internal powerflows.



Cheers

Greg Locock


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[moltenmetal]

You've over-specified the problem and should not be surprised at the lack of solutions being presented.

Here's one person's view of what the solutions might be. But they're predicated on the fact that we have an AGW problem to solve, and that solving it is both urgent and important enough to literally change our entire relationship WITH energy. That's not small, easy, cheap, or possible without sacrifice.

https://www.linkedin.com/pulse/what-energy-solutions-paul-martin/

(

http://www.spitfireresearch.com)

 

[LionelHutz]

Interesting, and there are some decent ideas there.

The argument for solution #2 has to be nuclear. Nothing else can be realistically built to produce drastically more electricity besides fossil fuels. Here, there was a big green push, but all the new green wind and solar sources still contribute only 10% to the total energy produced. Our grid is considered green only because we are lucky enough to have good nuclear and hydro installations, and little of that is anything new.

Solution #3 isn't realistic. There is no way solar and wind can produce the amount of electricity we use, let alone way more. Also, you can't partly load a wind turbine.

Solution #9 - Use less - Yes, that is the only way. Biofuel - No. House energy efficiency - sure, by getting rid of windows which are by far the most heat leaking part of a house nowadays, at least here. People in mass housing living at or near where they work is more realistic there.

 

[TugboatEng]

Also, you can't partly load a wind turbine

Is this true? Even a geared turbine on synchronous alternator has pitch control for the blades. Blade pitch can be varied to control output for constant speed operation. They might not individually have a good turndown ratio but multiple turbines in parallel can produce a very load flexible system.

 

[moltenmetal]

As the article says, if you think you can afford nuclear, you should build it. Forget about small modular nuclear plants, the notion that they'll make cheaper kWh than big plants is just a willing suspension of engineering economics.

(

http://www.spitfireresearch.com)

 

[moltenmetal]

As to not being able to partially load a wind turbine- that's just nonsense. They are variable pitch and can be feathered at will in less than a minute.

(

http://www.spitfireresearch.com)

 

[LionelHutz]

Well crap, he was going on about RE at home so I was thinking about how you can't partly load your home turbine like you can simply not use the output of the solar panels as his example talked about.

Anyways, the talk about ~simply~ building way more green production than we need in a discussion about how to lower the amount we're polluting the planet seems rather dumb.

 

[GregLocock]

Moltenmetal - I've pretty much specified the problem that east coast Australia faces. No nukes, 8 GW of coal generation closed down in the next 8 years, no more hydro sites. It is not overspecified, it is what literally needs to happen for the next 8 years. Every year.

Cheers

Greg Locock


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[GregLocock]

So, on an annual energy basis, UK experience is that offshore wind needs between 2.0 and 3.5 GW plate capacity to replace 1GW coal at 90%, and 3.2 to 4.5 for onshore wind. Australian large scale solar suggests 3.6 GW of solar to replace 1 GW of coal (UK is more like 10). We haven't got any offshore wind turbines in Australia, the estimate I have seen is that a 3.6666666 multiplier is needed. Which perhaps may be a number pulled from the air, if not a more unsavory source.

This ignores the intermittency/seasonal problem of course but does at least give an idea of the scale of what is needed, for the easy bit. I'm still working on the storage.




Cheers

Greg Locock


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[GregLocock]

This is the daily energy production from about half of the UK's OFFSHORE wind turbines, in January (ie winter when solar is useless and wind is are supposed to be strong)

[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1647583367/tips/image_thumb-65_nvhbzx.webp[/url]

So if we needed it for baseload, to maintain the average power out put we'd need to install 297 GWh of battery, about 6 days of average production.

As such minute to minute variability is not really important, you need to be looking at the day by day totals.

Now, if we overbuild the turbines, ie plan for less than 50 GWh/day , we can reduce the batteries required, while obviously spending more on building windmills for a given baseload. That's an interesting CBA, studiously avoided by the people making money out of this stuff.

https://www.lowcarboncontracts.uk/d...tual-cfd-generation-and-avoided-ghg-emissions

for several years of data including solar.

The other thing to look at is testing the claim that 'the wind is always blowing somewhere' and 'solar works when wind doesn't' -which is already dead in the water.

<Late edit, I got the units wrong in my post, they are GWh not MWh. still 6 days though>.

Cheers

Greg Locock


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[GregLocock]

That's just for one PV farm and one offshore wind station. Yes, there is a tendency for the wind to blow on gloomy days, and calm days tend to be sunnier, but there are plenty of exceptions.


Cheers

Greg Locock


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[Tmoose]

So the maximum PV solar out is about 2% of the wind station.

Is there any way to normalize the outputs to facility price or "size" ?

 

[btrueblood]

Greg - each data point in your scatter plot is a given day (i.e. that day's wind and solar output)? So there are a lot of points in the lower left quadrant where the combined output of the two is low...

 

[Pud]

I think you have to careful with UK data. The uk has a unique climate - it's called a West Temperate.
The closest is British Columbia.

(Why I remember this from school geography lessons 60 years ago I've no idea)


Politicians like to panic, they need activity. It is their substitute for achievement.

 

UK?

All bets are off for NW Europe when the global ocean current stops bringing heat from the Caribbean.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[TugboatEng]

Why would the currents stop? Is the moon going to fly away?

 

Shutdown of thermohaline circulation

Unlikely to happen suddenly, but then ocean changes are occurring even faster than predicted. But if it does happen to any significant extent, it is a massive game-changer for NW Europe, becoming colder not warmer.
(Ocean currents are not particularly influenced by the moon. You're thinking of tides maybe?)

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."