> And you can't either decide when people turn on their washing machine.

Not completely, but you can make electricity almost free at certain times of day to encourage shifting usage.

Although there is a natural limit to this, since people have to be home to do laundry!

(Also electric driers are the real culprit, they use an obscene amount of electricity! I am not sure if Germany is big on electric dryers or not though, that is something which is very culture dependent)

Power is far to abstract and far to cheap for people to make even the slightest adjustment to their habits. After all, lets say you knew that making your morning coffe between 07-08 cost 10 cents more than doing so an hour earlier or later, would you get up earlier, or go to work latter? And in 1 cent is more realistic.

Sure, but again the example was washing clothes, and clothes dryers use a LOT of energy.

Holy crap, doing the math a US style dryer would cost ~1.50 in electricity in Germany to dry one load of clothing.

Sources: https://www.globalpetrolprices.com/Germany/electricity_price... https://www.thespruce.com/how-much-does-it-cost-to-run-an-el...

So, like, you know, yeah. My dryer has a delay start function on it, if late night prices are 1/2 peak, then I'd save 75 cents a load. Let's say 3 days a week of laundry, $9 a month in savings.

Again, my dryer already does this, it isn't new tech, it is just nudging me to make use of the existing button that is already there!

US electricity prices are so low, eh, not really worth it for the state I live in.

Most people in Germany do not have an electric dryer.

Also, electricity prices are not the same everywhere. My parents for example pay only 20 ct/kwh (I have no idea how they got that contract, especially since they moved only last year. They have low overall usage though (2,000 kWh/a, with fixed cost being like 30% of the total bill)

Having a dryer is not the same as using it for all loads. Sometimes you need quick access to clothes. Work, spilling accident, not enough room for natural drying. In summer, if you can dry safely outside, that is a far better option.

One good example is electric car charging... all the EV owner has to do is opt in, and an algorithm can do the rest.

I don't think this is true. My (Dutch) mom used to wash at night and in the weekend because of reduced tariffs. She is very energy conscious on general. Not everyone is oblivious to these things, especially less well off people.

This is a syllogism and masks a complete mismatch of both demand and risks of windless days. There is no insurmountable problem if you accept a market in electricity in Europe, demand management (which already exists in the market in air-conditioning, freezing and thermal mass industries) and overbuild of supply. Not to mention storage.

It's not just a syllogism, it's a really weak one. You actually can decide when people "turn on their washing machine". It's called controlled supply, it's existed since the 1950s. Mainly for water heating but in principle any function.

So the thing about the earth is that it's big. If you have a big enough grid, it will be sunny and windy over a fairly consistent portion of that area.

It does not work that way. Long distance extreme high voltage transfer loses about 5% per 1000km, with the transformers adding another 10%, under ideal circumstances. In practice its higher, and thats on land. Sea cables lose 100x per km around 50% per 100km, again under ideal circumstances. In practice double the losses per distance, and if using existing grids, double it again, because most places dont build top end voltage grids.

Looking at maps for power prices with large hydropower dams you can easily see how most countries grids dont transfer more than around 1000km, and often quite a bit shorter. In practice this is the point where it becomes more cost effective to build new powerplants, than bigger infrastructure for transfer.

We could build grids designed for this, but never across oceans, and we are talking about an absolutely gargantuan investment, and its generally not considered as a solution for the unreliability of solar and wind. Its also why no one ever suggests to use the big empty oceans for truly large scale wind or solar etc, its always places very close to land.

Its also worth pointing out that superconductors cannot solve this, even if price and the gargantuan cooling energy requirements are ignored. This is because while superconductors transfer power without loss, they can only do so up to a limited effect, as the power interferes with the superconducting ability after that, essentially breaking it.

> Long distance extreme high voltage transfer loses about 5% per 1000km.

That's an incredibly low amount. Taking Berlin as an example, even 5000km lets you reach plenty of hot, sunny desert areas where any losses will be easily offset by vastly increased solar efficiency. Or you could spread out your wind energy sources to get more consistent coverage.

In fact that's pretty much what Singapore is doing: building a solar farm 5000km away in Australia.

They might be, but if so, that power is exclusively used in australia^^

1000km of ocean reduce transmission to about 0.1%^^

this was true with ac power cables, but isn't with hvdc ones. they don't have the same capacitance issues, and add such undersea cables are becoming more prevalent. a 1400km between Egypt and Greece is expected to be completed in 2023

HVDC brings that down to about 3,5% per 1000km even.

So you keep 70% of electricity piped from Morocco to the UK.

That sounds bloody swell. I'd pay for that in a heart beat.

The oceans kill it completely, remember two oceans of 100km reduce transfer by 0.75, and thats ignoring all the other problems with the grids on the way.

this is not true with hvdc http://www.diva-portal.org/smash/get/diva2:1187920/FULLTEXT0... has an analysis showing single digit percent loss for 500km.

We don't have a planetary grid (yet, at least). If there's a high pressure system across Europe, the whole continent can have low wind. This usually comes with either very high temperatures (in summer) or very low temperatures (in winter) which further stresses the system.

With the current technology, you can't transport electricity more than ~1000 km with acceptable losses.

Atmospheric depressions are bigger than than, and the distance for solar are much bigger as well (other than cloudy, there's day and night).

What do you consider acceptable? https://en.wikipedia.org/wiki/High-voltage_direct_current#Ad... puts the loss for HVDC at 3.5% per 1000km. That would imply 4000km with 15% loss, which is pretty good considering that wind and solar are significantly more than 15% cheaper than nuclear.

Specifically, https://en.wikipedia.org/wiki/Cost_of_electricity_by_source#... puts the cost of wind/solar at roughly 1/3rd the cost of nuclear, so it's more (cost) efficient to spend as much on transmission as you do on generation and build a really well connected massive grid than to use nuclear.

We can transport it a fair bit further than that, but only under ideal circumstances that are rarely met, and its very rare the grid is built for it, its never been needed after all. For instance, regulatory issues usually mean that every country border crossed tends to have a transformer station, which makes minor changes at a 10% or so efficiency loss.

Europe. Same grid. 8% losses

transmitting energy from other half of the earth (where is daylight when you are sleeping) is probably not best idea (not sure if even economically or technically possible). Also would be wise to turn off nuclear energy once you have this 'big enough grid'.

Is day and night really the problem here? Because I thought demand usually peaks at certain times of the day (e.g. early in the evening in California: https://www.pge.com/en_US/residential/rate-plans/rate-plan-o...), and actually bottoms out during the night. You would mostly use an interconnected grid (and storage) to compensate for this.

Also there is wind energy which doesn't care about whether the sun shines or not (actually it generates more energy when the sun isn't shining: https://www.scientificamerican.com/article/wind-power-turbin...).

In most of the Europe the biggest use of energy for family will be heating except summer. In the future probably also charging electric car. This kind of power demand you need mostly at night when sleeping - during the day you are probsbly in the office.

Transmitting power also consumes energy - you cannot have a electric wire across pacific to transmit power from US to EU without transformers - electric power line is not a fiber optic that transmit just signal.

I also doubt we have enough rare earth minerals to make all those magnets for wind turbine and and electric car enough for whole planet. Remember also you have to decomission those windturbine after some years which is expensive

At least in The Netherlands we mostly use centralised (gas-powered) heating, so nuclear energy is a tangential factor. Also there seems to be room for improvement in insulation and centralised thermal storage (warmtenet in Dutch). Electric cars seem both like both a problem and an opportunity, because you could charge them while being at the office and partly use their batteries for powering your home at night (in case you don't need a full charge to get to work in the morning).

Regarding rare earths, we will need them regardless of using nuclear or renewables for electric cars, so that seems partly tangential. For wind turbines their reliance on rare earths seems troublesome. It's geopolitically ironic that we (Western Europeans) get our gas from Russia and our rare earths from China.

Electric cars are currently mostly charged at night (since that's when electricity is cheaper), but as solar becomes more prevalent, that will swap. Charging cars during the day is pretty easy, just require office parking lots to have chargers (and possibly subsidize).

You are right that you can't have an electric wire across the Pacific to get power from the US to the EU, but more because the EU doesn't border the Pacific. On a more serious note, Novia Scotia to Ireland is about 2600 miles, so it's on the edge of doable with HVDC, but it would be a massive project and slightly hard to justify.

I'm interested to know what rare earth metals make up so much of a wind turbine. According to https://www.nrel.gov/docs/fy17osti/66861.pdf (page 65), around 99% of a turbine is accounted for by steel, fiberglass, iron, copper, and aluminum.

The one project that is likely to actually come into fruition is the HVDC cable betweebn Iceland and UK for wind power:

https://www.offshorewind.biz/2021/05/24/usd-30-billion-north...

Whats funny about this is, that the wind farm will not even be connected to Iceland itself! I guess they have such great geothermal resources that they don't really need more power.

Well, it is obvious, that the renewable production needs to be paired with some on-demand sources. Short term, gas is great for that, as gas power plants can be switched on and off quickly, long-term the necessary storage options are needed (some of that can be power2gas, which can be burnt in the gas power plants).

> Short term, gas is great for that

Still an unacceptable CO2 emission in my book. Natural gas is at 55,82 [kg CO2 / GJ], when coal is at 94,6 [kg CO2 / GJ]. [1]

So that's only 40% less pollution, and there are still huge quantities of coal that has yet to be replaced in Germany.

What's missing from your view is how you provide for baseload. Right now, what is baseload in Germany? It is coal: https://app.electricitymap.org/zone/DE

[1] https://www.volker-quaschning.de/datserv/CO2-spez/index_e.ph...

Going to chime in with my usual statement, "baseload" as a concept only applies if you have energy sources which are cheap to run but can't scale up and down quickly. That is no longer the case.

What you mean to say is "we need to provide power all the time".

Gas is better than coal in a strict sense, and a combo of gas and renewables will vastly reduce emissions, and in a way most people can deal with. Over time battery prices will fall and renewable install base will rise so that gas peaked eventually become unnecessary.