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dust42today at 9:48 AM6 repliesview on HN

I once read an article that in Berlin the sewage system is flushed with fresh water because too many people have installed water saving toilet flushers. So plenty of people bought these water savers and now the price of water has gone up because the water that is directly flushed needs to be paid too.

The 'balcony power stations' are the same thing. They get subsidised, and you even get a fixed kWh price when pushing into the grid.

The problem is that in the end it will become more expensive for everybody because at times you have a surplus driving the whole sale electricity prices into the negative while still paying fixed prices for injection into the grid.

To make this economically viable, you have to have everyone paying spot prices. Everything else is just green ideology driven inefficiency.

Just to make it clear, I think renewables are an important option for the future. But to make them a viable option of the electricity energy mix, supply and demand, storage and grid capacity need to be taken into account.

Last not least, there is plenty of low hanging fruit to drive CO2 emissions down: drive up the truck tolls. Currently you have potatoes farmed in Germany, driven to Poland to get washed, transported to Italy to be converted to french fries and transferred back to Germany into the super markets.

Same goes for home office, during Covid it was possible for many workers to continue with their work. Does an accountant need to drive to an office every day? Nope. How many business trips could be replaced by a video call?

If the CO2 emissions problem is to be solved rather sooner than later, the money has to be spend efficiently as there isn't enough of it.


Replies

Xylakanttoday at 6:15 PM

The price of water has gone up for a multitude of factors. One of them is water savings in general, but not primarily because the sewage system requires regular flushes. The reason is that water gets paid per qubic meter and includes a fresh water and a waster water component. The assumption is that almost all fresh water you use ends up as waste water. Now, the grid has a very substantial fixed-price component that's largely independent from the actual current volume being used. Putting pipes in the ground and maintaining them there is an actual costly endeavour. If water use now drops, and the baseline cost remains stable, then it's entirely expected that the price per volume rises. It's simple math. The same baseline cost needs to be brought in via less volume.

This will also happen to people that use residential gas. As less and less people use residential gas, the maintenance of the gas network gets distributed among less and less customers.

> The 'balcony power stations' are the same thing. They get subsidised, and you even get a fixed kWh price when pushing into the grid.

They are subsidized on purchase, but the price they get when pushing energy into the grid is by default fixed at 0. The network accepts the power, but there's no payment. It's also capped at 800W delivery, meaning that at peak power generation, you'd earn a whopping 5 cent an hour with the current subsidy for full scale solar power. So in practice, the only benefit owners have is that they draw less power from the net which is much more attractive because of the pricing structure. You can, optionally, register your balcony power station as a regular solar power plant, but then you're subject to a whole bunch of rules and regulations (for example you need a suitable elctricity meter etc.). This option is generally not attractive for such small power generations.

Fundamentally, though, the same issue as with the water and gas network exists with all localized (solar) power generation. If more and more people use the grid only as a backup, or for winter energy needs, then the overhead of maintaining the grid will have a larger cost contribution to the total cost of electricity.

tjansentoday at 10:10 AM

As soon as everybody is paying spot prices, balcony power stations are not economically viable anymore. Even today, on a sunny day, spot prices for electricity are either very low or even negative. The more solar power is available, the lower these prices will be. So your balcony power station is replacing electricity you could get for free anyway. At night, when you are not producing electricity, you still need to buy the expensive electricity from fossil plants.

The reason why personal solar installations are profitable is that you can buy electricity for fixed prices from your local power company. You pay the average of the vastly different low (or negative) prices during the day and the extremely expensive prices on windstill nights. Solar allows you to use your own electricity when the average is below spot prices, and get power for much less when the price you pay is cheaper than spot prices. It's like a state-approved scheme to play the market in the name of decarbonization while actually increasing everybody else's prices and possibly even CO2 emissions.

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pjc50today at 9:55 AM

> They get subsidised, and you even get a fixed kWh price when pushing into the grid

Neither of these is going to be true for the UK balcony scheme (you can't get export generation pricing unless it's an MCS-certified install).

> drive up the truck tolls.

The price of diesel is going to do this anyway very soon.

watwuttoday at 9:53 AM

> I once read an article that in Berlin the sewage system is flushed with fresh water because too many people have installed water saving toilet flushers. So plenty of people bought these water savers and now the price of water has gone up because the water that is directly flushed needs to be paid too.

What is this supposed to mean? You flush less water, therefore water price is more expensive, because flushed water needs to be paid too?

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vrganjtoday at 9:57 AM

Thinking of this in terms of markets is the real ideologically driven inefficiency.

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Gibbon1today at 9:54 AM

I have the curse of having an mom who was a smart CPA.

All this stuff root top solar, plug in solar costs at least twice what utility solar. And only makes sense when you have messed up rate setting schemes that enable arbitrage.

But it's not what you want if you want to get the most GW connected as fast as possible.

Like the requirements that new houses have roof top solar. You could get twice as much if you just invested the money in a conventional solar farm.

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