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Equivalent of 97% of Scotland’s 2020 electricity consumption was from renewables

bbc.com

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Re: Equivalent of 97% of Scotland’s 2020 electricity consumption was from renewables

#201

Post by mpweiher »

martinald wrote: post #11

Really misleading article IMO. What this actually means is Scotland sometimes generated 200-300%+ of its demand from wind (and "exported" the rest), and sometimes low %age points and used other sources/imports. It makes it sound like Scotland is wind powered 97% of the time (only 3% more to go!), which is very different. There is an increasing crisis in the UK of negative electricity prices (typically when it is sunn…

> crisis in the UK of negative electricity prices

Yes. And this is often touted as "renewable now cheaper than..."

But those decreasing prices are not actually a sign that renewable energy is cheaper to produce, but that it is actually useless and thus worthless at certain times.

Now that may entail some business opportunities, but it's not that simple. For example most industrial applications can't easily be turned on or off as the wind blows and the sun shines.

Re: Equivalent of 97% of Scotland’s 2020 electricity consumption was from renewables

#202

Post by WalterBright »

martinald wrote: post #11

Really misleading article IMO. What this actually means is Scotland sometimes generated 200-300%+ of its demand from wind (and "exported" the rest), and sometimes low %age points and used other sources/imports. It makes it sound like Scotland is wind powered 97% of the time (only 3% more to go!), which is very different. There is an increasing crisis in the UK of negative electricity prices (typically when it is sunn…

This sounds like consumer electric rates are fixed 24/7. Fixed prices always lead to gluts and shortages.

Having prices vary minute by minute depending on supply will create powerful incentives for users to shift their demand. As I've written here many times, there are many many ways people can shift their demand.

Such as running the hot water heater only when electricity is cheap. Charging your electric car battery only when cheap. Etc.

Re: Equivalent of 97% of Scotland’s 2020 electricity consumption was from renewables

#203

Post by kwhitefoot »

missedthecue wrote: post #55
eldaisfish wrote: post #30

Earlier quoted context omitted.

Have you heard of Tesla's batter in south Australia? It was recently expanded to 193 MWh. Care to guess how long it'll run at full power? Around 60-100 minutes. At its rated power of 100 MW, it can power around 25% of South Australia's lowest demand. That's it. At peak demand, the fraction is lower still. Cars have a fraction of the energy storage capacity of a single battery site and not all cars are connected to th…

I don't know if there's enough lithium in the world to stabilize a global renewable grid and make 100 million electric cars per year forever and make 1.5 billion phones a year and all the other things we use batteries for.

Lithium is very abundant. It's the 25th most abundant element at about 20 mg per kg in the Earth's crust. It is present in seawater at a concentration of about 0.2 ppm in seawater, about 230 billion tons total.

If electricity is going to be so cheap then we can just extract lithium from seawater.

Plus dead lithium batteries can of course be used as a high grade ore.

See https://en.wikipedia.org/wiki/Lithium

Re: Equivalent of 97% of Scotland’s 2020 electricity consumption was from renewables

#204

Post by mnw21cam »

sandworm101 wrote: post #145
piokoch wrote: post #35

Earlier quoted context omitted.

Yes, the point with selling electricity is that you need to guarantee that you will deliver some fixed amount of electricity. If you depend on wind power plants how this guarantee can be given? What if wind stops. Maybe it would make sense to build huge bitcoin mining data centers and mine bitcoins in case of surplus. Hardly useful, but given current coins rush could be profitable. Better than paying producers for no…

Aluminum smelters. If you have lots of cheap power you can always smelt. The raw materials are everywhere and everyone needs aluminum products. Fill the pots and spark up the electrodes as soon as power gets cheap. https://en.wikipedia.org/wiki/Aluminium_smelting

Yes, all true. But, you also need to keep the "pots" quite warm (at least 960 degrees C) in order for the electrolyte to be liquid. Keeping them that temperature while not actually producing any product (while electricity is expensive) is a waste. The article you cite says that the Australian smelters that are used to iron out changes in electricity demand can't be switched off for more than 4-5 hours, or they may be damaged by the liquid solidifying.

Re: Equivalent of 97% of Scotland’s 2020 electricity consumption was from renewables

#205

Post by kwhitefoot »

aclelland wrote: post #33
IAmEveryone wrote: post #20

Earlier quoted context omitted.

Electric cars are perfect for this. Connect them to the grid and the internet, and they’ll charge but also feed back as needed.

I've seen this suggested often but I don't think I've ever seen any information about how it'd actually work in practise. Do the car companies actually want to do it, how is the car owner compensated for the battery wear and tear and who'd be in control of the management (government regulators, energy companies, car manufacturers). Are there any examples of pilot schemes that have used cars in this way?

Nissan and Hyundai already produce cars with vehicle to grid (Nissan) and vehicle to load (Hyundai).

Re: Equivalent of 97% of Scotland’s 2020 electricity consumption was from renewables

#206

Post by ryathal »

jliptzin wrote: post #121
martinald wrote: post #11

Really misleading article IMO. What this actually means is Scotland sometimes generated 200-300%+ of its demand from wind (and "exported" the rest), and sometimes low %age points and used other sources/imports. It makes it sound like Scotland is wind powered 97% of the time (only 3% more to go!), which is very different. There is an increasing crisis in the UK of negative electricity prices (typically when it is sunn…

You have to be really unimaginative to consider a surplus of renewable energy a crisis.

Everything exists in a Goldilocks Zone, too much power can be just as bad or worse than too little power. It's far more likely that the excess power causes damage or other negative results than anything good coming from it.

Re: Equivalent of 97% of Scotland’s 2020 electricity consumption was from renewables

#207

Post by sliken »

CraigJPerry wrote: post #100
captainmuon wrote: post #77

Earlier quoted context omitted.

This. Transition to renewables is not just about replacing power plants, it is about changing demand structure. Negative prices are an incentive to build power buffers, or to use power when it is plenty. You can even do crazy things like make steel. One funny side effect that might happen is that for individuals, power will not become more expensive from renewable energy, but rather cheaper - so cheap that the meteri…

It would be cool if i could use an electric car parked at home during the day to store some of that cheap electricity then spend it from the car back into the house at night. When i looked into this last, it wasn’t common to have that bi-directional power flow capability. There was one, very expensive, Mitsubishi solution on the UK market around 2 years ago.

Buy a powerwall or equivalent, they are designed for this use case, they tune the battery chemistry, cooling, weight, etc for this use case.

Wearing out a expensive electric car, with a high load, while it's not moving (harder to cool), to save a few pennies per Kwh isn't worth it. Keep in mind that there's power losses just charging and discharging, so you need a pretty big swing to make it worth while.

A powerwall (11kwh) costs $7500 or so installed and is generally enough to "peak shave" by charging when power is cheapest and discharge when it's most expensive. It does lower electric bills, but generally isn't really a good financial decision unless you put a financial benefit of having power when during outages.

Re: Equivalent of 97% of Scotland’s 2020 electricity consumption was from renewables

#208

Post by opwieurposiu »

avianlyric wrote: post #143
wcoenen wrote: post #56

Earlier quoted context omitted.

It might work, but it's not necessarily going to be very profitable. The equipment that sits around waiting for low or negative electricity prices represents locked up capital, and ongoing maintenance and depreciation costs. For the same reason, it's not a good idea to have bitcoin mining equipment sitting around waiting for cheap electricity. The hardware becomes obsolete very quickly, so there's only limited time t…

With negative electricity rates you can do crazy things like buy thousands of space heaters, and just heat the outside. Space heaters don’t become obsolete, and they’re not very capital intensive, or require much maintenance. You just need space to put them in.

You can buy a 10MW load bank on alibaba for $40k

https://www.alibaba.com/product-detail/11KV-10MW-Load-Bank-f...

Sometimes power plants have GW size load banks, it's an acre or so of steel wires strung up on poles. All the wires glow red hot when in use. It is quite a sight.

Re: Equivalent of 97% of Scotland’s 2020 electricity consumption was from renewables

#209

Post by WalterBright »

dahfizz wrote: post #163
pydry wrote: post #45

Earlier quoted context omitted.

>There is an increasing crisis in the UK of negative electricity prices It seems like an opportunity more than a crisis to me. There are tons of potential applications for "free" electricity. * Storage heating/cooling that's basically free * Manufacturing carbon neutral jet fuel * Cheaper aluminium production It could also lead to onshoring of certain industries which previously moved to locales with access to cheap…

Is electricity the primary cost for the things you list? Once you have paid for the factory, equipment, employees, materials to manufacture aluminum or jet fuel, I can't imagine the stakeholders just shutting everything down if the cost of electricity fluctuates. For actual buffers to be developed, we need applications that are super cheap to set up but expensive to run. Storage heating / cooling is a good idea, I ca…

> from the top of my head

Charging your electric car battery.

BTW, heating/cooling my house is half my energy bill. Time shifting that could easily cut that by a third. All I need to make that work is variable rates. But with fixed 24/7 rates, nobody has any incentive to do that.

Re: Equivalent of 97% of Scotland’s 2020 electricity consumption was from renewables

#210

Post by VBprogrammer »

bluGill wrote: post #142
VBprogrammer wrote: post #64

Earlier quoted context omitted.

The challenge with this kind of stuff is that capital costs are a big part of the cost for large industrial plants. A plant which is only using 25% of its capacity is going to be unprofitable.

When the biggest input cost is energy you are wrong. A plant that is 10% capacity by running only when energy is cheap is more profitable than a plant at 90% running at whatever energy prices are. (in the real world take my numbers and reduce by 75% - between nights, weekends, and maintenance shutdowns a real industrial plant at 25% capacity is already common) The company I work for has two plants near each other, wh…

Without knowing what industry you are talking about it's hard to engage in any meaningful dialog.

It clearly doesn't matter what percentage of the input cost is energy to whether the plant is profitable. So long as that percentage is non-zero there will always be an energy cost at which the total cost to produce is higher than the market price to sell (ask any industry in Texas).

Clearly there are other factors too, in your example it seems like labour costs are very high or perhaps contractual demands on output mean down time is unacceptable.

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