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Ask HN: What is the biggest challenge for solar energy?
31–40 of 44 posts
Re: Ask HN: What is the biggest challenge for solar energy?
#32Earlier quoted context omitted.
But why is this a big problem now ? If we covering 100% of our needs when the sun does shine, I would get it. But we are nowhere near there right ?
Because there are fixed costs, and you need to pay for all the infrastructure in case it's a cloudy day. Imagine there is a car that costs $10,000 and works every day, or there is a car that costs $3000 but works only every other day. But you need to drive every day. Does it make sense to buy both cars and drive the cheaper one on sunny days? No, economically you only buy the reliable car and you don't buy the unreli…
I'm sorry I still don't understand why this is the biggest problem now. I get why it's a long term problem - that for sure.
But, your comparisons are about building new stuff. My understanding is that the gas / coal capacity is already there - so it's not a question of adding more, right ? So we don't have those fixed costs - they are already paid. We already have 100% of coverage with those, so adding solar, even without storage, will indeed decrease those variable costs.
Economically speaking, if we say solar is cheaper than gas / coal - what's preventing a rational actor from installing more capacity ? Until we get to 100% solar on sunny days, he is sure to sell 100% of his production if it's cheaper gas / coal no ?
Re: Ask HN: What is the biggest challenge for solar energy?
#33Earlier quoted context omitted.
Because there are fixed costs, and you need to pay for all the infrastructure in case it's a cloudy day. Imagine there is a car that costs $10,000 and works every day, or there is a car that costs $3000 but works only every other day. But you need to drive every day. Does it make sense to buy both cars and drive the cheaper one on sunny days? No, economically you only buy the reliable car and you don't buy the unreli…
I'm sorry I still don't understand why this is the biggest problem now. I get why it's a long term problem - that for sure. But, your comparisons are about building new stuff. My understanding is that the gas / coal capacity is already there - so it's not a question of adding more, right ? So we don't have those fixed costs - they are already paid. We already have 100% of coverage with those, so adding solar, even wi…
> So we don't have those fixed costs - they are already paid.
No, that's generally not how infrastructure is funded. Infrastructure is funded by bonds that are sold and have to be serviced. So the payment for the fixed costs is spread out over time -- ideally over the lifetime of the asset -- and what happens when you add unreliable source that are cheaper -- like solar -- is that they cannibalize the revenue stream used to service the debt and those plants are taken offline right now, or they have to be subsidized somehow by the taxpayer -- which is why regions that make a big push to solar end up paying high energy prices and need to import a lot of energy. They are not paying high energy prices because solar is expensive, but they end up paying high prices to keep their reliable plants online. Or they require subsidies from the taxpayer. California is one example, but you see this often in Europe as well. California just got a billion dollar Federal subsidy to keep diablo online for a few more years, but the reason it was going to go offline was because it needed massive subsidies to remain operational in a market in which it competes with solar. But at the same time, solar can't replace Diablo without blackouts and water shortages - Diablo supplies 10% of California's energy and is used to pump water, so this is something that requires reliability, but it is losing money every year because it's cannibalized by solar. That's the situation of the household that chooses to buy both cars -- that household has to spend a lot more.
Solar has basically made nuclear uneconomical in the U.S. because nuclear has massive fixed costs but almost no variable costs, so it can't exist in a de-regulated market with solar -- the solar just drives it out of business. At the same time, solar is driving greater use of coal because coal plants have the cheapest fixed costs. So Germany was ditching nuclear and using more coal as a result of deploying all the renewables. If you don't pay extra to maintain your reliable capacity, you get blackouts or pay emergency rates to beg for energy from your neighbors (California has to import 20% of its electricity).
Rational actors -- like the household choosing between the two cars who knows they need to drive every day -- are required to plan for sufficient capacity look at this and say "we're not ready to deploy solar at scale" because they want to avoid the blackouts and price spikes. Politicized actors choose a different route, and you get the energy mess that is California, UK, Germany, etc. And all of that is solely because of storage, and it gets worse the more solar you deploy without storage.
Re: Ask HN: What is the biggest challenge for solar energy?
#34Earlier quoted context omitted.
I'm sorry I still don't understand why this is the biggest problem now. I get why it's a long term problem - that for sure. But, your comparisons are about building new stuff. My understanding is that the gas / coal capacity is already there - so it's not a question of adding more, right ? So we don't have those fixed costs - they are already paid. We already have 100% of coverage with those, so adding solar, even wi…
> So we don't have those fixed costs - they are already paid. No, that's generally not how infrastructure is funded. Infrastructure is funded by bonds that are sold and have to be serviced. So the payment for the fixed costs is spread out over time -- ideally over the lifetime of the asset -- and what happens when you add unreliable source that are cheaper -- like solar -- is that they cannibalize the revenue stream…
Well that's fascinating, thank you very much for explanation !
Re: Ask HN: What is the biggest challenge for solar energy?
#35There is no big problem with solar energy. In the US at least the industry is installing as much new solar as possible.
Take a look at this EIA webpage [1]. Of all the new installed capacity in 2021, solar constituted 39%, followed by wind with 31%. Natural gas comes at a great distance, with 16%, and the next one is not really a source of electricity. It's batteries, with 11%. Nuclear comes with 3%. So, the only new installed capacity that can produce CO2 emissions is natural gas, with 16%.
EIA does not have the split for 2022 yet, but a quick google returned [2], that shows solar kept its share of 39% through the first half of 2022. It would have been higher, but for the supply constraints. Going forward, it is expected that new solar installation will increase significantly, not in small part due to the Inflation Reduction Act.
[1] https://www.eia.gov/todayinenergy/detail.php?id=46416
[2] https://www.seia.org/research-resources/solar-market-insight...
Re: Ask HN: What is the biggest challenge for solar energy?
#36Earlier quoted context omitted.
It would be great if they could achieve this goal. What options do you see that could be used right away?
I think as of today the most efficient approach is pumped storage hydropower. However that is severely limited by geography
A good example is the large scale hydropower project in Switzerland where they added 900MW capacity to the grid for storage. They do have a good geography for that.
https://www.reuters.com/business/sustainable-business/switze...
Re: Ask HN: What is the biggest challenge for solar energy?
#37The grid isn't optimized for it, and the base generation is highly incompatible with the fluctuations wind and solar create. There are very real costs to rapidly cycling power demands on steam turbine driven generators, regardless of what fuel is used to generate the steam. Each heat/cool cycle causes microfractures in the shafts to grow just a bit, and those have to be bored out periodically to remove the cracks, an…
See MGA Thermal for a way to store heat at high density and temperatures that can take steam to drive gas/coal turbines.
Re: Ask HN: What is the biggest challenge for solar energy?
#38Earlier quoted context omitted.
I'm sorry I still don't understand why this is the biggest problem now. I get why it's a long term problem - that for sure. But, your comparisons are about building new stuff. My understanding is that the gas / coal capacity is already there - so it's not a question of adding more, right ? So we don't have those fixed costs - they are already paid. We already have 100% of coverage with those, so adding solar, even wi…
> So we don't have those fixed costs - they are already paid. No, that's generally not how infrastructure is funded. Infrastructure is funded by bonds that are sold and have to be serviced. So the payment for the fixed costs is spread out over time -- ideally over the lifetime of the asset -- and what happens when you add unreliable source that are cheaper -- like solar -- is that they cannibalize the revenue stream…
Wow! Thanks for the great explanation!
Re: Ask HN: What is the biggest challenge for solar energy?
#39I think it is political will and long term thinking. Even today, aerial view of any place shows what a missed opportunity lies below. So many parking lots that could be covered ones with solar panels on their roofs(who invests on adding the panels? If I want to, would I be allowed to?) Same goes to the roofs of several businesses, supermarkets etc. It is not their core business to buy solar panels and invest for the…
Actually the EU is thinking about exactly doing this.
https://energy.ec.europa.eu/topics/renewable-energy/solar-en...
Re: Ask HN: What is the biggest challenge for solar energy?
#40The economic advantage in delaying. Given the large build outs and that you don't want to replace panels for 15+ years, a Moore's law like rate of improvement often seems like a reason to wait and pay less for better panels that will have a higher productivity.
How could this be changed?