Hacker News new | ask | show | jobs
by RAM-bunctious 716 days ago
I think it's clear that solar panels, while working today, clearly haven't been able to solve today's problems, or else this discussion wouldn't be happening. But we should keep investing in them, one way or another.

Similarly, we should keep investing in the prospect of commercially viable fusion reactors. The harnessing of fusion reactors would be instantly revolutionary as opposed to the incremental progress solar promises. Therein lies the difference. Once is not necessarily better than the other.

And it's not a zero-sum game.

4 comments

I would say it’s clear that solar panels are absolutely working extremely well today, at least as long as you don’t live too close to the poles.

Renewables all together is growing faster than nuclear ever did. And solar is now a huge part of that.

We have models where solar or solar+wind is providing all the power to everything from small remote weather stations through houses to large islands. Some small countries and regions are getting close too.

It’s clear that we have all the technologies we need to do 100% renewables. There’s studies that indicate that the long term costs of this is lower than the traditional fossil and nuclear energy infrastructure. We just need to build the factories to continue scaling up. And of course the transition is more expensive than it’ll be when we just maintain and expand on the system.

> all the power to everything from small remote weather stations through houses to large islands

Not without very large capacity gas/etc. plants available on standby (unless you’re fine with will below 99% availability)

I'm fine with gas plants available on standby. If they run 1% of the time, then they are no longer a significant contributor to climate change.

Even if they have to run 10% of the time, we've still taken an enormous cut out of greenhouse gases. We would turn our attention to many other sources of greenhouse gas (agriculture, concrete, transportation, etc.)

Or batteries.

Batteries have huge potential, simply due to the fact that they're so broadly defined - must store energy, output it as electricity on demand, and be cheap. There's a high chance that we find some way to make grid-scale batteries extremely cheaply, in the future.

In the mean time, getting to 90% will basically stop climate change in its tracks, giving us time to research dirt-cheap batteries.

It doesn't even have to always be electricity on demand, sometimes we also need heat. I wonder if heat storage will be a thing we'll have in the households (or maybe it's enough to have it in district heating facilities?).
The gas can be hydrogen, produced with renewable electricity by electrolysis.
Don't molten salt and similar energy storage technologies augur well for that?
The nice thing about power plants on stand-by is that they emit almost no pollution.

(And yeah, batteries will probably never be enough for any place out of the tropics.)

We have to get fine with below 99% availability.
Less then 99% means not having a working fridge for 3-12 hours or more in 30c heat so there went all your perishable foods. It means no lights in the house will work. No cooling or heating of any kind. No computers. No phone. None of your other random applicances will work either. None of the stuff you use to navigate a city like street lights will be working. Of course it can be mitigate with a generator or an expensive battery bank with solar panels provided you don't have a large enough load. Of course solar panels only work during the day so if the outage lasted into the night then you better hope to have a large enough bank to power all your essential equipment.

Suffice to say, less then 99% available is pretty terrible. You should come down and talk to a South African.

> or an expensive battery bank

Expensive for now. I'd expect that to be a cheap battery bank in <10 years.

Based on what?
It depends how that's distributed.

If we had one hour per day without power that would be about 95% availability. Most of us wouldn't even notice that if it happened in the middle of the night.

If we had 100% availability with an 18-day stretch without power that would be about 95% availability, but it would be hugely disruptive.

Why? I don’t agree that wouldn’t be at all acceptable.

And even > 90% would be very expensive to achieve in winter in much of Europe (of course there are alternatives to solar so it’s not such a huge issue)

Go to a country with just that and witness how stupidly wasteful it is to have an energy grid with regular outages. Everyone who can afford it has an expensive backup generator, batteries, etc. For industry, it's a disaster.

I live off-grid, with solar and LifePo4, but I'm not naive enough to think that would scale to an economy any time soon. And for the record, no below 99% availability should be seen as unacceptable.

Why would we do that? I'd rather pay more than this.
Don't take this the wrong way, but I envy your naivete. You are extremely optimistic about people and politics.
How so? To my ears, "we need to accept significant degradations in the availability of electricity" is a deeply pessimistic statement.
The implication is that it's a voluntary political decision to forgo more reliable sources of electricity. There's basically zero chance of that happening in any political entity, hence that expectation is optimistic.

Of course, it frequently happens involuntarily, and just saying "get used to it" is pessimistic, as you say.

Both reflect the same thing: it's politically untenable to voluntarily accept poor reliability of electricity supply.

That’s funny. My take is exactly the reverse.

Solar power can 100% solve our energy needs today. It’s cost effective at the unit level. It works at scale. It decentralizes nicely. Did I mention that it works? Every home could have rooftop solar for less than it costs to produce centralized power plants. (I have rooftop solar and it cost significantly less than a new car now my power costs won’t go up for 20 years at which point the panels might need a refresh but that part of the system is the cheapest part)

We could easily flip from subsidizing fossil fuels to subsidizing rooftop solar today and realize significant gains (higher roi by shifting the investment). If you spent one years investment in fusion and fossil fuel subsidies on deploying rooftop solar and grid scale batteries you’d change the energy story permanently. Energy would suddenly be plentiful. Fossil fuels would permanently shift out of relevance. Fission reactors would look like quaint and staggeringly expensive tools of a bygone age. And fusion which DOES NOT WORK. Would look even more like a silly dream.(We are no closer to fusion than we were 30 years ago.)

Why the fuck are we still talking about fusion when we have something that works?

I agree with everything you say about rooftop solar. If you have a suitably unshaved roof, and you are in a reasonably sunny climate, the current economic math works. And as energy costs go up, and capital costs come down it works better all the time.

That said, we still need a grid to distribute electricity to places that consume more energy than roof space. Think apartment blocks, factories etc. And yes, a huge chunk of that load can still be supplied by grid-scale solar and wind etc.

Even with large-scale storage (another fruitful place to spent investment money) there's going to need to be peak-generation.

However you look at it, I don't think fusion will be the answer. Since fusion was first proposed and the landscape of requirements have shifted. By the time it's practical, it'll be solving a problem we dont have.

The science may lead to a working reactor. But no one will build it at scale because it simply won't solve the problem well have then.

Grid scale storage has lagged behind solar and wind generation, but it's starting to catch up. By the time we have a viable commercial fusion power plant all of the grid storage issues will have been long since solved.
Find the graph of GW of solar installed over time