Solar for the home

Daily Life, Swiss News and General Topics
21
Because if you use the batteries to feed into the grid, you can only do this when their is daylight and the cars are often out at work.

If you drain the batteries at night, you need to recharge them before the cars can move again.

What if the next day is not sunny....? you "give" the electricty company your KW's at Chf 0.0813/kw and then need to buy it back the next day at Chf 0-23/kw

Who covers the guarantee on the batteries as they are not being only used by the car so why should the manufacturer cover the costs of deteroration by frequent charging for use other then the car is designed for. The manufacturers will know exactrly the charging cycles of the batteries via software.

The only car i know that this MAY be possible with is the Mitsubishi Outlander plug in hybrid.

Using car batteries to supply the grid is utopique, not properly thought out and not really feasible. (you would need an inverter to do this)

22
Tesla won’t do this. They claim it will degrade the battery prematurely.

Some Kia, Hyundai and possibly some VW id models have vehicle to grad ability. But judging by YouTube videos this is mainly for making cups of tea and charging other cars...

23
...experience of the last 2 winters at 450m which is closer to the altitude most on here live at.

Winter 2020/21 was very snowy but still cleared from the roof in 1 to (at worst) 2 days - basically as soon as there was a decent amount of sun. Panels are pretty slippery allowing the snow to slide off fast (I made sure I didn’t have snow catchers) and as soon as a bit of black panel shows the sun heats it up nicely.

24
It depends on the angle of the panels/roof. Mine's 45deg. at 425m. Even so we had 2 days with zero power after the big snowfall of 2021. This last winter the snow had sipped off by midday...

25
LFP batteries have many more cycles than standard Lithium-Ion batteries.

Of course, it does not make sense for a single car.

But imagine having millions of cars with batteries that can achieve high cycle count.

Also, imagine having every possible building with solar panels, feeding into the grid.

Now, if your car is at work, you could top up there, from the grid, taking in the energy generated by the solar panels elsewhere.

Of course, the losses occurred would be significant (charging, storing, giving back...). But still, it's not like petrol and diesel that is gone once you burn it.

Solar + EV is really a vision, a long-term goal.

26
Sorry I'm a bit late to this one. Perhaps this information might help inform you. My partner and I recently installed solar panels (building-integrated, 17 kW) on our roof and included a 15 kWh battery. Everything was done by SelNET (located in Basel). I've been collecting data since it was all connected and switched on at the beginning of April.

The solar panels on our roof (52 x 330 Wp) cost CHF 15766.

The two inverters cost CHF 2686.

Our battery cost CHF 8910.

Since the system is building-integrated (i.e. the tiles were removed entirely) it's significantly more expensive than simply mounting panels on a frame on the roof. We also included a specialized window module (instead of a solar panel) and that alone cost CHF 4800, even the single 'blind' module installed (because of a vent) was CHF 280. All up we spent CHF 71000 done and dusted.

We use heat-pumps for hot water and heating (replaced older electric boiler and oil-burning heater last year) and our house is not exactly minergie (built in the late 1950s), so it was an expensive winter for us (approx CHF 950 for electricity for Nov, Dec and Jan - approximately 4.5 Mwh of power used over those three months). The roof was uninsulated, so as part of our roof renovations we had it insulated properly. We've also replaced the front door and some windows to improve matters.

During April, the battery would usually fill up and get us through the night. Some nights it would run out of juice just before dawn. Early this month SelNET came around and did some optimization (getting the solar system and our heat-pump heating system to communicate and improved the efficiency) and now we are using less than half the battery capacity each night.

I calculate that we've saved CHF 210 since the beginning of April (42 days, still on Standard tariff - Primeo Energie, Baselland). Over that period we consumed about 1 MWh of power, of this only needing to import 210 kWh from the grid (though about 80 kWh were imported before the battery was installed several days after the panels were switched on). We are under no illusions that our system will pay itself off anytime soon.

So to get to your questions ..

i) is the battery worth it?

Not from a financial perspective. But we like the idea that we are capturing some of our own solar energy and using that during the night, rather than grid power. That said, most of the grid power we previously used comes from hydro and/or nuclear. As long as it wasn't coming from burning coal or the dreams of children I wasn't unhappy with buying electricity. So, for us the battery is just a nice experiment.

ii) need to collect data for a year before they can tell you what size battery you need.

Really? That seems like the sort of answer somebody gives when they cant be bothered to access readily available data and work it out. Useful estimates are available.

iii) they can sell you a 12 kWh battery for CHF 13500

Ours is 33% bigger than that and 33% cheaper. The first reply to your post by Tom1234 is bang on the money. Get another quote to compare.

I hope our experience helps you with your decision.

Cheers,

DKH

27
We were quoted a 12Kw battery last year for CHF 7500.

So definitely worth shopping around.

28
Unfortunately, historical prices mean nothing these days.

We’re not in Kansas anymore.

29
There seems to be a substantial mark-up charged. I was looking at self-building a system and batteries alone should be around 350 per kWh. Of course, you have to add on a few other items and installation.

30
Return tariff for solar power will be increased

Photovoltaics (PV) is a pillar of the energy future, and the WWZ has always been committed to promoting the expansion of this technology. The price that WWZ pays solar power producers has already been one of the highest in Switzerland.

As of 1 October 2022, the WWZ will increase this return tariff from 12.3 cents/kWh to 19.0 cents/kWh, thereby offering regional FV operators an even more attractive fee for electricity from their own roof – and also providing an effective incentive for accelerating the expansion of photovoltaics in the region.

Source https://www.zug4you.ch/en/news/news-...prices-in-2023

31
A friend of mine in the UK built out a huge solar array with battery. There, consumer electricity prices are capped, but when he sells back to the grid, it is at uncapped wholesale prices. He's making money hand over fist.

32
Looking for a reality check:

We are exploring putting in solar.

The three providers in the area charge between 2500 to 4000 to provide a quote for the project.

I will need quotes from different providers, at least two, preferably three, so am looking at a fairly hefty price tag just to get started..

Is this price for a quote in line with what you all have paid?

Many thanks.

33
You can also use a local community solar organisation to do this. This will give you a good estimate of costs.

34
Certainly never had to pay for a quote. Mind you that was 2 years ago...

There's people out there who do on-line quotes. Got 3 when we were planning ours (2 local plus IKEA), the result was pretty close to the final estimates and the final bill.

Even 2500 is way ott imo. Solar installation is a pretty standard job, the main issues come if the roof is too weak - which isn't a solar problem per se.

35
Found a link. There are also many local organisations: https://www.e-wende.ch/

There's a calculator on there which where you can select your roof from a map and it can make some estimates for you.

36
This sounds like a windfall bonus for solar installers.

We paid nothing for quotations...

37
Given the current energy situation, I'm guessing they have more work than they can do and are charging accordingly and also not wanting to waste time on quotes that go nowhere.

38
Also, anyone on here who had solar done who is willing to share some of the documentation/details with me? I'm interesting in what kind of gear was installed and any paperwork signed with energy company etc.

39
Yes, but I don’t have time at the moment to look it all up for you. Maybe in a couple of days...

40
Firstly, I familiarised myself with what is involved and terms like "string" and "inverter" and watched YouTube videos on installations.

I concluded that I would need a company that did everything for me - planning permission etc. etc. In fact all 4 I looked at did that. I think all Swiss installers do. You can find some nifty stuff online that use Google earth make suggested positions for panels on your roof.

Having seen the market I wanted the best and most efficent panels and inverter. I photographed where the sun fell on the shortest day, and the lower 3rd of the roof was in shadow. So I had a good idea where and how many panels would work.

The company I finally went with installed top quality gear and their salesman seem straightforward and honest. He promised they would take care of everything from planning to final independent inspection. All I needed to do was inform our electricity supplier (EKZ) online short details of what were up to and the billing was automatically adjusted to pay for what we put into the grid.

The only problem was, I signed up and paid 20% deposit in January 2020 with an estimated installation date of March 2020.

In the event, the company was totally overloaded and after dozens of phone calls and emails, the installation was made in September 2020.

An independent outfit called Pronovo.ch are in charge of subsidies and they paid based on the kWh peak of the system (9.6kWhp) they paid about 6 months after it was running. Again a short online form.

Hope this helps!