I don't get why we (Germany) don't support PV on roofs much more than we do right now.
I would be happy for the government to pay me to save on my electricity bills by installing PV on my roof but I suspect they might not be so keen on the idea. Loans instead? Maybe, but there are all kinds of issues around what happens if you need to sell the property etc.
Same with industrial units. You could have an enormous room that would cost £500K to install PV onto which would be way too much money for most building owners unless the feed-in tariff would cover the cost quickly but why should it? The Energy companies don't want to pay for a feed they might not need at any particularly time of day. Australia had big problems with over-supply of solar at certain times and I believe the rate went negative to try and stop people feeding it in.
For me, solar thermal for hot water is a far more reasonable position, certainly on new build domestic properties. We all use a lot of hot water, even during the summer and having water heated by solar thermal apart from being really effficient, masssively reduces the (usually) gas burden of heating from a boiler or immersion heater.
I also love the idea of a partnership between, e.g. An Underground Station with a limitless supply of heat energy to remove to cool down the stations, and perhaps the hospital next door which uses enormous amounts of hot water. Heat pump anyone?
This one is very frustrating. The core of the issue is the lack of long-term strategy. It has been obvious for decades that paying now is orders of magnitude cheaper than bearing the consequences of things like climate change and a dependence on a madman dictator hell bent on revenge with delusions of grandeur. But the practical solutions are screws that we can’t really use with our free-market hammers.
Probably best to seperate people knowlingly lying about science/politics/economics to suit themselves from the activities themselves, though that can be complicated at times.
That’s right, we could have done more even within a somewhat free-market framework. Though a lot of people would argue that the moment the government has to step in with incentives and taxes it ceases to be free; this was an argument that was used against cap and trade, for example (though even cap and trade is a terrible solution anyway). These solutions would not really help with large infrastructure projects or the lack of will to address dependence to Russian gas, for example.
You can mess up carbon taxes by setting the wrong price, not increasing it predictably over time or exempting certain sectors, mismeasuring or whatever. That's basically the same things you can mess up with Cap and Trade.
Cross border effects have impacts too, but there's no fundamental reason why carbon pricing or cap and trade wouldn't be a good solution to weaning Germany off Russian gas.
This is almost certaintly untrue, in both the wider and narrow senses.
Basically, solar alone will never cause negative prices or 'oversupply', because solar can switch itself off fast enough that any solar bidding a negative price to the market would just turn itself off rather than pay money to someone who uses the power. The same is true of wind turbines.
Because you reference Australia, it was almost certainly coal plants that were bidding negative because it would cost them more to ramp down and back up again as demand changes.
There's some incentive regimes, that can lead to renewables offering to pay people to take their power (if they get paid $X for each used watt, then they can pass some of that subsidy on to a user rather than stop providing) but that's a good thing, not a bad thing. It's just a price signal that rewards flexible demand.
In the words of an Australian coal energy producer:
https://www.stanwell.com/our-news/energy-explainer/negative-...
> Negative prices are a signal to either increase demand or reduce supply. Intermittent and fast response energy sources (such as solar, wind, peaking generators) can stop and start in relatively short spaces of time to avoid negative price periods. Coal-fired generators however, incur significant costs stopping and starting and require many hours to restart. This means they continue generating throughout negative pricing periods as it is more cost-efficient to incur the costs of negative pricing than shutting down and then starting up again. This ensures that they are available to meet peak demand in the late afternoon and evening once the intermittent sources such as rooftop solar and large-scale solar are no longer available.
Wouldn’t this make the panels hotter? I’m guessing they’d accept (or should accept) a slightly negative price but because that’s better than dumping the energy through the panels themselves via excess heating.
That's not how solar panels turn themselves off, however. To turn a solar panel off, you just disconnect it. It will produce a voltage (which is why handling an uncovered solar panel can be a shock hazard), but no current. It's not dumping the power, it's actually producing no power in the first place (voltage times current is zero when the current is zero).
It is cheap on industrial and warehouse roofs, and extends the life of the roof. But they coexist well with pasture and crop land uses, too, as well as reservoirs and canals.
So space for solar is absolutely abundant everywhere.
If you mean slanted shingle roofs the installation is still trivial.
There are also plenty of flat residential roofs which are exactly the same as an 'industrial' roof.
There's multiple factors that feed into this, such as how much supporting infrastructure is amortized vs scale, being able to design the array for optimal lighting vs working with an existing building, systematic regular cleaning to keep the array working near peak efficiency... lots and lots more details like that.
This isn't to say residential rooftop solar is bad. However atm it's something of a vanity project for people who can afford the investment. It is most definitely not some sort of obvious solves the whole problem slam dunk idiots in government are ignoring because they're stupid. They know what they're doing and are focusing on the highest impact places to put funds, and that can scale up a lot faster than fighting NIMBYs.
And yeah, I'm really disappointed in Elon's solar roof tile stunt surrounding this.
The thing is, there is no slam dunk obvious solution. But every bit that helps could be part of a more global solution that has a chance of working. Public transport, better insulation, electric transportation, solar panels and wind turbines where it makes sense, large-scale carbon-free baseline production, etc. We need to do all of that.
> And yeah, I'm really disappointed in Elon's solar roof tile stunt surrounding this.
Elon is not on the right side of this. His pseudo-ecologist speeches are just window dressing.
On very large commercial buildings, a project may claim economies of scale, and support dedicated personnel to keep them operating well.
That said, roofs are far from the best place to site solar.