1) a battery is not worth having
2) the solar needs to be on for a year before they can say what size I need
3) they can sell me a 12 kWh battery for CHF 13'500
Any comments on these 3 points please?
Further, what I really would prefer is to have my house off-grid. The solar I have been quoted for requires electricity from the net to function. So, no mains, no solar. Does anyone know if any firms are installing off-grid systems for family homes?
Thank you for any helpful comments.
The quote sounds quite reasonable. You probably can half it by buying materials from China and sourcing the handwork on tutty.ch, at your own risk.
I'd avoid batteries, too.
Off-grid in Switzerland, IMHO, is unrealistic or very inconvenient.
See where you consume the most of electricity, and try to cover it with solar. Maybe you can achieve 80/20 % roof/grid rate.
I think , at least heating can be done by solar only, but you'll need a very large, well insulated water tank (or multiple tanks) to save the energy in hot water for a foggy day, instead of saving it in batteries. You can find a 1000l electric boiler for below CHF 1000K. May need 2 or 3 of these.
Thanks
You'll never make this money back.
Batteries are a good idea for night use, espeically if you have only 1 tarif, but the technology needs to improve still, which it will, and the price needs to come down significantly.
Also remember, and nobody selling tells you this, during summer night time electricity use is far smaller than winter, but in winter, solar panels, whilst still working do not work as well or as much a summer !
Also depending on altitude where you live, solar panels don't work iof they have snow on them , and heating them to melt the snow takes far more energy rthan they produce before you ask
To Aza : Where exactly do you find a 1'000 litre electrtic boilere for less than Chf 1'000.-- care to post a link maybe ?
Here in Switzerland I've only seen rules on how the system should be installed. Also, what documents (mainly plans) need to be submitted to local authorities to be shared with firefighters so they don't get hurt while putting off a fire in buildings with solar installs no matter the fire source. No major technical challenge but I'd bet all this costs money.
Batteries can start a fire too but the risk is minimal if competent electrician does the job. I don't own a home, so no idea if insurance is impacted by having a large amount of batteries under your roof.
Financial side?
Batteries do not make that much sense economically. Energy is lost while charging the battery. Engineers will say better send back extra energy to the network instead of storing it locally. Batteries make sense when there's no network on when living off-grid is more important than money. I guess telling smugly to your neighbors you charge your car from your roof is something worth paying.
Environmental concerns.
The objective of solar is to reduce the environmental impact of electricity generation. But batteries are far from being "green". Minerals coming from war zones, mining minerals without minimizing environmental impact, lack of certainty about recycling, etc.
Lots of people are working on making greener and bloodless batteries, advances are made every day, but we're not there yet. It seems there will be better batteries in a few years, better wait.
With trains, when they apply electric braking the generated power must go back into the grid or dissipated by heat, meaning additional components.
His view reflects the above... it maybe worth putting panels on your house but only if a big incentive is helping the environment. Domestic batteries are still 3 to 5 years away from being economical (depending on advances in solid state tech).
The big 'scandal' is that the energy companies could 'easily' ramp up huge solar farms that would significantly reduce fossil fuel demand. It's at scale that PV makes economic sense..but.. as he ruefully pointed out.. that would mean enormous changes in how large providers operate and they're not prepared to write off their existing investments in fossil fuel infrastructure.
Forget batteries. Forget being off grid unless you are a hippy. You can’t be off grid and still have grid for bad weather days because when there is a power cut solar systems shuts down automatically to avoid electrocuting engineers working on cables. That said I’ve lived in Switzerland for 33 years and have never experienced a power cut.
Subsidies vary by canton. Zurich give back an amount based on peak output. We got just over CHF4000 back. The electric company (EKZ) pay from 1 Jan this year CHF0.09 per kWh put back into the grid.
The total installation cost (approx CHF32,000) is tax deductible for the year of installation - something our salesman didn’t mention.
We run 2 electric vehicles from the solar. Our annual bill for electricity (heat pump) is about CHF900. I hope with the increased subsidy this will come down this year.
To my mind solar is to help the environment as much as save any money.
I cannot recommend the Swiss company who installed the system. Their engineers and installers were excellent, but their admin was hopeless. We were given an installation promise of March which turn out to be September...
Quick search brings up something like this :
Photovoltaics were still too expensive then, my calculation showed that cost return would take 30 years, so I went for "Erdzonden-Wärmepumpe" which kind of works, but turned out not an ideal not an ideal solution, as it heats to 55C at best.
Now cost return seems to take less that 20 years.
The 1000l boiler I bought in Germany is a "Hygienespeicher" - it means that the water you use has no direct contact with heating elements, so it remains drinkable. It works quite well if you consume the water slowly, but if the family uses 2 showers at the time, the water runs too fast through the warm exchange system and may get colder at the end, even though still warm in the boiler.
Mine, in addition to input from the Wärmepumpe, has a built-in 400V 4KW electric heater with thermostat, which lets me heat up to ca. 70C when I absolutely need it (like, a crowd of guest staying overnight)
To the OP, check carefully what subsidies you can get your hands on. Between these (we found 2, one national and one local) and the tax deduction our 12.2 KwP roof cost about CHF 12K net from 25K gross.
I'm sure you know best
P I've produced just over 50 MWh in just over 3 years, i'm South facing and at 800m. Snow doesn't really melt when the temp has a problem getting over 0°C and the glass panel underneath also stays cold preventing melting.
I don't know if that is possible already - and if it become possible at a later date, your hardware knows how to do it or if you have to through a couple thousand more towards it...
https://www.uvek-gis.admin.ch/BFE/sonnendach/
The good thing about Switzerland is that AFAIK the whole country is cataloged.
They have a database of every single house in Switzerland, with orientation, inclination, shape of the roof.
Just enter the address and it tells you how much energy you can expect to "harvest".
If the batteries are LFP, they should last very long.
Once you "upload" to the grid and your batteries are empty you begin using "their" electricity which is usually about 3 times the price of what they pay you for "your" electricity......
The price of a battery system and the price they pay you makes this really a non starter.....
12 Kw at Chf 0.12/Kw (very generous, more like Chf 0.08/Kw) makes Chf 1.20 per full battery ands a battery costs ............Chf 13'500.--
It is all done instantaneously, no waiting around to see if you may use it or not, you either use it or sell it to them,.
https://blackout-news.de/aktuelles/k...altungen-2022/
But I agree, batteries are mostly a thing you want, rather something you need.
If a lot more houses had solar cells, feeding back a small amount of your stored energy into the grid from the battery that you know you will not need (because you're not planning to use the oven and only use the stove for a short while, for example) might actually make sense.
Likely, this could be semi-automated with ML that learns your habbits.
Whoever gets this done first and properly and has a large base installed will likely be able to generate nice profits.
Probably wouldn’t work for everyone but for some it could be win-win.