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Comment by jacquesm | Hacker News Reader

Continent sized landmasses can survive on wind and solar assuming HVDC interconnects.

Some storage would be nice to have, preferably more than a weeks' worth.

Let's approximate the cost of that. The energy consumption of my country (the Netherlands) was 3157 PJ in 2017. This was 980 kwh per person per week. Solar batteries cost a bit more than $1000 per kwh. So at these prices this plan costs approximately $1 million per person. Solar batteries last 5-15 years. If we say that they last 20 years, then the energy storage costs are $130 per person per day per week's worth of storage. This plan sounds feasible if costs come down by factor of 10.

How does it compare to the cost of a nuclear power plant?

Storing a weeks worth of consumption on a 'per person' basis can be done for a fraction of $1m. But energy scarcity will lead to an increase in prices, which in turn will lead to a reduction in consumption. One big problem with energy is that it is still way too cheap.

Another problem is that there are a lot of subsidies involved for large consumers as well as extra taxation on small consumers.

Generating that amount of energy using nuclear would cost approximately $13.4 per person per day (IIRC ~3x what we're currently paying for it). Note that I have not included the cost to generate the energy in the $130 storage costs, but that cost is negligible compared to the $130 anyway.

The environmental damage would probably also be much less with nuclear, versus a ton of solar + wind + batteries. But there would be disaster danger. It is unclear to me how the danger of nuclear disaster would compare to the danger of running out of stored energy in a winter month.

> Storing a weeks worth of consumption on a 'per person' basis can be done for a fraction of $1m.

How?

Since the costs of storage are currently so huge, it seems to me that if you want to go the solar + wind route, it makes sense to overprovision energy generation. That would reduce the amount of storage you need, and the extra energy during summer would be somewhat useful. Note however that you would need massive amounts of wind+solar.

For an average household to satisfy its electricity needs, it needs ~10 average size solar panels (assuming perfect storage). However, household electricity use is only 5% of our energy use. So to satisfy energy needs with solar, you need approximately 200 solar panels per household. Even if you round that down to 50 due to reduction in energy consumption and use of wind energy, it's still a lot. But the Netherlands is obviously not a very good country for solar. In countries like Australia, the numbers would look way better.

Energy is too expensive, not too cheap. The real problem is that the market is distorted by subsidizing some forms of energy production and failing to price in the negative externalities of others.

The problem with your reasoning is that no cost-optimal plan of providing the society with energy would call for a week's worth of batteries. Furthermore, another problem is that judging from the number, you're presumably calculating with annual primary energy spent per capita, which will not be the same number after electrification (electrification is expected to massively slash primary energy expended -- for example in cars, where ~20 kWh of electricity replace ~6 liters of gasoline, primary energy shrinks roughly by a factor of three). Therefore translating current primary energy consumption into electricity that will need to be stored in an electrified future is nonsensical.

A factor of three (which is very optimistic) doesn't change the conclusion: a week's worth of storage is not feasible with current battery technology, let alone a few weeks.

How much storage would actually be required is not clear to me. It depends on a lot of factors. A week doesn't sound totally crazy to me; we certainly want a good safety margin so that society doesn't collapse in a bad winter. If we take super optimistic numbers and have one day of storage and take your factor of 3 reduction in energy use, then the cost of storage alone would still be about twice what we currently pay for the energy. Expensive but certainly a cost that would be possible to pay.

> A factor of three (which is very optimistic)

For cars, the factor of three is not "optimistic", it's simple comparison of the respective primary energies consumed by typical vehicles in their respective categories. 20 kWh to drive 100 km = 72 MJ of primary energy. 6 liters of gasoline to drive the same distance = ~220 MJ of primary energy -- roughly triple of the former number.

> A week doesn't sound totally crazy to me; we certainly want a good safety margin so that society doesn't collapse in a bad winter.

Yes, but that doesn't imply you need the capacity to run the country 100% on batteries for a week. That's just not something anyone would ever do. For example, a gas turbine with a low duty cycle would definitely be cheaper than a battery after a certain period of time. So why would you use a battery for that?

The specific factor for cars is not relevant. The factor of 3 is wildly optimistic for general energy use. The point is that even taking the factor of 3, it's still extremely expensive.

Regarding the second paragraph: if you point is that it would be cheaper to duplicate a significant portion of our energy generation, one based on renewables and one based on fossil fuels for safety...that is perhaps true, but that only proves the original point, so I'm a bit confused why you phrase your replies in an antagonistic tone of voice when we seem to agree.

It was an example, since obviously different uses of energy will have different improvement factors - but major uses of energy have considerable improvement factors. In case of heating, for example, the factor is theoretically infinite because it's possible to build net-zero-energy buildings. And specifically in case of Germany, a very large portion of natural gas consumption goes into heating, so this is quite relevant here.

> if you point is that it would be cheaper to duplicate a significant portion of our energy generation, one based on renewables and one based on fossil fuels for safety...

I didn't say a word about basing something on fossil fuels.

> that is perhaps true, but that only proves the original point, so I'm a bit confused why you phrase your replies in an antagonistic tone of voice when we seem to agree

I don't see how we "seem to agree". The comment I initially responded to was proposing storing a WEEK's worth of PRIMARY energy in TODAY'S amounts in BATTERIES. Nobody would seriously consider such a contrived scenario; it would be completely pointless. So I can't possibly agree with those numbers.

I find it fascinating that you call me nonsensical for making the very reasonable assumption that energy consumption will stay the same for a back-of-the envelope calculation, and here you are talking about infinite improvement factors.

> I didn't say a word about basing something on fossil fuels.

You said: "Yes, but that doesn't imply you need the capacity to run the country 100% on batteries for a week. That's just not something anyone would ever do. For example, a gas turbine with a low duty cycle would definitely be cheaper than a battery after a certain period of time. So why would you use a battery for that?"

> I don't see how we "seem to agree". The comment I initially responded to

Note that I responded to that comment with a calculation showing that that plan is economically infeasible. The scenario is not all all contrived; what that person proposed we need is reasonable, and it would in fact be quite dangerous and insufficient to have only one week's worth. Years in which there is more than a week without wind and hardly any sun (due to winter) occur approximately every 10 years in Germany. Thus calling a week's worth of storage contrived is just wrong. If anything, it's contrived in the direction of not being enough.

Where did you get 1,000$/KWH of storage? Even at small scales (household-sized batteries, ~10~15KWH) prices are currently around 300$/KWH for lithium batteries including shipping in a 3rd world country (I know, because I live in a country where there's no 24/7 grid power and I moved my house to solar+batteries 2 years ago).

I'm pretty sure at the kinds of scale you'd need for a country price per KWH would be significantly less.

I just googled solar battery cost and took the cheapest in the result that came up: https://www.solarchoice.net.au/blog/battery-storage-price/ It is possible that the numbers that come up there are too high.

This is an extremely naive assumption.

Do you have any citations for such a theory?

Everything I’ve read on the subject (admittedly not much) tells me that wind power is not only a disaster ecologically (kills too many birds, though not as many as domestic cats) but also unable to produce enough power to govern everything even with interconnects.

Distribution of power is also difficult, but there was notably a “still” winter in Sweden which is driving up prices significantly due to hydro not being enough. (I live here, that’s how I know)

I don't really understand the strong position you take while at the same time admitting to not having read much on the subject, and then to regurgitate a bunch of debunked nonsense.

This is not a good basis for a discussion.

“Citation please”

“Everything I have read contradicts what you just stated.”

Not sure how I could be clearer. Maybe I made a mistake by admitting my ignorance, but i would rather admit my ignorance than assume I know everything because I read 5 articles and watched a few YouTube videos.

For starters HVDC lines are being installed in many places and many are already operational, and the 'windmills kill too many birds' thing was a push by the fossil fuel industry and has been debunked.

I don't know which five articles you have read but I suggest you read a couple more and more recent ones.

As for 'citation please': that does presume that you have done your own homework, I really don't see why I should do it for you but as to those first two points of yours:

https://theconversation.com/wind-farms-are-hardly-the-bird-s...

and

https://en.wikipedia.org/wiki/List_of_HVDC_projects

Some of those links are well over 1000 km long.

I appreciate the citations and I will read them.

> I really don't see why I should do it for you

Because the burden of proof rests with the person making the claim.

Only if the claim is an outrageous one, which it really isn't in this case.

To you.

Windmills do kill birds. That isn't seriously disputed. Some large wind farms have had a significant impact on threatened bird species. We might consider that an acceptable cost but the issue hasn't been debunked.

https://www.sciencedaily.com/releases/2016/09/160929143808.h...

Yes, they do kill birds. But you know what? Buildings kill a very large multiple of that and housecats a very large multiple of the buildings. So no, they're not meatgrinders. Yes, some threatened bird species were impacted disproportionally, but any change would impact them because there are so few of them left, which is usually because of other causes: Windmills tend to be situated rather closer to the habitats of large birds of prey than housecats and buildings because we left them very little habitat to begin with, and neither large birds of prey nor windmills work well in an urban setting. But taking good care of this when siting windparks can alleviate a lot of that particular concern.

So yes, the 'windmills are bird killers' theory has been debunked to the extent that it was previously pushed as a false reason to not install windpower. (See for instance: https://windmillskill.com/blog/windfarms-kill-10-20-times-mo...)

There was a whole campaign around this, including endlessly recycled gruesome material of the same 25 birds that at one time flew into a particular mill. Obviously that stuff has legs because hey, gore and something I don't want in my backyard.

I always wonder what drives people to push these issues for more than they are worth.

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