Also included is a battery (9.something kWh IIRC) and a charger for an electric car.
My parents don't have 50k in their name....
Break-even as calculated by the seller would be after 14 years.
I told my dad that it looks like a good motivation to get 90 years old then, if nothing else.
As a refresher, I have 17 kWh of roof-integrated panels in a less-than-ideal orientation (12 kWh West facing, 5 kWh East facing) and with some shadow from trees and neighbor's building. I also have a 15 kWh LiFePO battery.
The point of this post is to give some insight about the usefulness of the battery. In an imaginary utopia, the battery would fill every day and would drain to the minimum (mine stops yielding power when it drops to 5%) just at dawn the next day. Repeat. That would represent the maximum usage of the battery - fill it every day with PV power that would otherwise be sent to the grid and use all of that captured power every night.
But since I dont live in that imaginary utopia, I have to accept that the battery will operate at somewhat less efficiency. Over the Winter, it never got higher than 20% charge on any given day and drained to 5% every night. Some days, it never got more than a couple of percentage points of charging. During the Summer, sure it charged to 100% every day, but it discharged only about a third of its capacity overnight - so we could have gotten away with a 5kWh battery and still had 100% self-sufficiency. It's only during Spring and Autumn that we more closely approached the utopian maximum usage of the battery's capacity, fill to full during the day and drain to empty overnight. But it's not sunny every day, so there were only a few days when the battery filled and drained completely. This was entirely expected of course.
Over the course of a year we used 6.8 MWh of power to run the house. Of that, we had to buy 2.7 MWh - the rest, 4.1 MWh, came from our panels and solar-charged battery. The battery by itself saved us from having to buy 1.9 MWh.
The battery and it's installation represented about 20% of the total cost of our PV system. The solar power it captured supplied 28% of the power we used (admittedly, this is nearly entirely neidertariff). So ... battery good! Well ... battery ok, at least.
DKH
For 10kw i get Chf 0.189/KW = Chf 1.89 for 10KW
My night tariff (when i need the stored electricity) is Chf 0.25/KW so Chf 2.5 for my 10KW
So the calculation for the saving is actually, night tariff - injection price, so .....Chf 2.5 - Chf 1.89 would save me Chf 0.61 per 10KW
Having said that, I still don’t think they pay as a stand-alone. But I would be interested in having a car battery that can be used as an overnight supply.
As for using a car battery, great, so battery is uncharged in the morning when you want to use the car.....who covers guarantee, the manufacturer, despite battery not being used for the purpose it was sold for ?
It sounds great but in practice......
As for car as a home battery, not all of us commute by car you know? Plus the typical commute does not use anything near the full capacity of most car batteries. The concept is already implemented by the VW group (and I believe one or two Japanese manufacturers).
https://www.volkswagen.co.uk/en/elec...y-storage.html
Might not fit you but it could help many others.
I think Tesla does not currently allow this but seeing other manufacturers allow it might push the market in that direction
But the VW soluton suits my lifestyle nicely! AFAIK this should extend to other ID platform cars from Seat and Skoda eventually if not already.
Admittedly, with a lower price for re-injected electricity, you may save about 10Rp/kwh, which means your battery might pay for itself in as little as 50 years.
So economically, makes no sense. Ecologically --- it is a different topic but also makes little sense IMHO
No way, physically maybe but with a very highly reduced charging capacity, this is a well know fact and accepted by all.
Ive had solar panels on the roof for a few years chugging away at paying for themselves in some far away date.
Anyway, the house is a bit old fashioned and we still have an electric water boiler. My mate reckons we would do really well to put one of these in https://www.solarguide.co.uk/solar-i...sts-benefits#/ which is using excess photovoltaic to heat water (as opposed to the actual "heats the water" solar systems which as I understand it are a bit rubbish). This looks like a great idea but I can't find any swiss equivalent or any docs on whether this is fine in CH or you need to ask for permission.
does anyone know ?
CHF 0.189/KW........fairly good,more than 50% of price you pay !! (In Vaud/Romande Énergie)