[cycomanic]

Capacity factor is calculated into lcoe, what's your point? Moreover, downtime for wind turbines is much less of an issue for a grid than large power plants (even with a significantly higher capacity factor), because you run into much bigger issues if your GW plant is down, compared to a couple of MW (and no the probabilities of all your renewables mix going down at the same time is very low, unless you're Luxemburg).

[Manuel_D]

Capacity factor is calculated in. But intermittency is not. The issue is that once demand is saturated during periods of peak production, the excess energy is wasted so the effective capacity factor drops as adoption grows. E.g. once you saturate daytime energy demand, further investment in solar energy yields no more useable energy.

Intermittent sources are a good way to supplement dispatchable sources of energy like gas plants or hydroelectricity. But as a primary source of energy, they're not feasible without a massive breakthrough in energy storage.

[brohee]

The effect of overcapacity is null or negative price, which has the property to make more storage viable (who cares if it only gives back 25% if the input is free or very cheap), so I'd say intermittent sources overcapacity is an enabler of on grid storage.

E.g. today in Germany you can buy MWh at 14€ at 13:00 and sell it back at 180€ at 18:00. I didn't look all of Europe but it looked like the biggest spread today... You can make money with crappy storage under those conditions...

[Manuel_D]

This is precisely why intermittent sources aren't viable without a breakthrough in energy storage. Existing storage mechanisms aren't capable of delivering at the tens to hundreds of terawatt hour scale required to make intermittent sources viable.

Remember, 66.8 TWh of electricity is used daily. Intermittent sources don't just experience daily fluctuations, but seasonal fluctuations lasting days or weeks. Even 12 hours of storage would still leave us with periods of insufficient production multiple orders of magnitude more frequent than the status quo: https://www.nature.com/articles/s41467-021-26355-z

[cycomanic]

> Capacity factor is calculated in. But intermittency is not. The issue is that once demand is saturated during periods of peak production, the excess energy is wasted so the effective capacity factor drops as adoption grows. E.g. once you saturate daytime energy demand, further investment in solar energy yields no more useable energy. > > Intermittent sources are a good way to supplement dispatchable sources of energy like gas plants or hydroelectricity. But as a primary source of energy, they're not feasible without a massive breakthrough in energy storage.

Intermittent sources are baseload, your argument applies to any baseload system, I.e. you always need some additional dispatchable energy source (unless you over build by large amounts). Again if your main energy would be e.g. nuclear you need even higher amount of dispatchable power because if your nuclear plant goes down (planned or unplanned) you need to compensate for a lot of power.

[alvah]

>Intermittent sources are baseload

This statement is about as incorrect as it is possible to be, as even a cursory attempt to check this before posting would show.

It is difficult to understand why anyone makes claims such as this, unless they are consciously or unconsciously attempting to redefine a word that already has a well-understood meaning.

[Manuel_D]

"Base load" refers to electricity demand, not sources of electricity. Things that consume electricity are a "load". The "base load" is the level of energy demand that is always present in the grid. E.g. if a grid consumes 5 GW of electricity at peak demand, and 4 GW at minimum demand, then 4 GW is the base load.

[adgjlsfhk1]

it's possible (and fairly easy) to build infrastructure that only turns on when there is excess energy

[Manuel_D]

You can see the breakdown of electricity usage here: https://www.eia.gov/energyexplained/electricity/use-of-elect...

For residential uses, heating, cooling, and refrigeration are the main uses.

For commercial electricity use: computing, refrigeration, cooling, and ventilation.

For industrial electricity use: machine drive (lathes, mills, etc.), process and boiler heating, facility heating and cooling, electrochemical process.

The only categories that I guess could be easily shifted is process and boiler heating. But some industrial processes need to run uninterrupted for weeks. Machine drive, perhaps, but then workers would not be able to work a regular schedule. Not to mention, industrial applications in total is less than 25% of electricity use.

Demand shifting is a lot easier said than done. I see it proposed very frequently, but I've yet to see a detailed plan for what electricity uses will be shifted, and how.

[moooo99]

> For residential uses, heating, cooling, and refrigeration are the main uses.

Heating and cooling can be offloaded into grid peak availability hours relatively easily with the price serving as a reliable trigger. This assumes proper insulation for the most part, but is viable and using the price as an indicator automatically sets up the right incentives. As for refrigeration, the energy use for that in a private household seems to be overstated.

> For commercial electricity use: computing, refrigeration, cooling, and ventilation

For cooling the same applies as for private households, maybe to a lesser extent. The other loads remain pretty static in their demand, but once a commercial operation has a certain scale building out the own battery storage to optimize for purchasing price (assuming a flexible price that reflects spot pricing) may be a viable strategy.

> For industrial electricity use: machine drive (lathes, mills, etc.), process and boiler heating, facility heating and cooling, electrochemical process.

For boiler heating and facility heating and cooling the same applies as for commercial and residential uses. For other energy intense workloads, demand shift is already frequently happening because the ROI is fairly quick. It’s not easy to assess from the outside because you do need an in depth process understanding that you just cannot provide as an outsider. But I have personally witnessed plenty of examples that demonstrate it is well within the realm of possibility

[Manuel_D]

Heating and cooling cannot be easily load shifted. Daily fluctuations in energy production aren't the only forms of fluctuations. Seasonal fluctuations are large, too. And the seasonal variation has the unfortunate tendency to line up with periods of high energy demand. "Just don't heat your house in the winter" is not a viable form of demand shifting.

> For boiler heating and facility heating and cooling the same applies as for commercial and residential uses.

Note that this refers to "process and boiler heating". There's plenty of industrial processes that need to be kept at temperature for long periods of time, otherwise the batch is ruined. Titanium smelting is one example. I've yet to see a breakdown of what specific industrial processes can be shifted.

[AstralStorm]

Heating and cooling can only be offloaded in extremely wellinsulated houses. A lot of the ones in the UK do not make the cut. Even some new EU ones do not.

If you try to offload it otherwise you just waste power heating/cooling yourself at wrong hours.

A boiler in this setup is a thermal battery. These are good, but space consuming and relatively failure prone and expensive to maintain. Inefficient compared to central too.

[specialist]

Are you arguing for or against offshore wind?

Tackling climate crisis requires All The Above.

Wind, nukes, solar farms, tidal, whatever, by themselves, aren't silver bullets.

We also need heat pumps, renovations (insulation, air sealing), district heating, etc. That's just for housing.

We could also talk all day about industry and agriculture.

As the saying goes: The opportunities are insurmountable!

[devnullbrain]

This is about the UK. We're now less than 5 years away from when every new car will have a battery. In 10, none of them will have an engine.

[alt227]

The deadline in the UK is currently 2035.

Labour have pledged to bring it back down to 2030, but when they begin the talks with the motor industry to try to achieve this they will fold like they have done several times so far in this government.