ᐅ Single-family home photovoltaic system with 30 kW capacity

brandner1860 schrieb:

I think I will stay below 25 kWp.

You can also install the modules first and connect anything above 25 kWp later as a new system. The same applies to the 30 kWp limit for income tax purposes.

brandner1860 schrieb:

I estimate the annual consumption at 4.5 kW, since I also want to install 2 or 3 split air conditioning units.

With a heat pump and air conditioning, expect more around 6,000 kWh.

If you do self-installation, it can still be economical even with the 8-cent feed-in tariff. So: cover the entire roof!

Zubi123 schrieb:

The same applies to the 30 limit for income tax.

That is incorrect. The total output per operator counts. The only workaround would be if two systems are operated separately by each (spouse) partner. In this case, the timing does not matter; they can be installed simultaneously, of course as separate systems with separate inverters.

As far as I know, it is not possible to exceed the 25 kWp (25 kW) limit per connection. However, I am not 100% certain about this off the top of my head.

filosof schrieb:

I have two storage units: one with 42kWh and one with 84kWh.

The great thing about them is: they even have wheels and a steering wheel, so I can take them on vacation!

As long as they don’t feed energy back into the system, they are technically more consumers than storage units. I’m definitely curious about bidirectional charging. Unfortunately, neither our system nor our BEV supports it at the moment. It’s a pity that even as an off-grid solution, it’s still a real rarity.

Allthewayup schrieb:

In any case, I’m curious about bidirectional charging. Unfortunately, neither our system nor our BEV can handle it at the moment.

Oh, people have been waiting for that for a long time. Since when did VW plan to equip its ID fleet with bidirectional charging capability?
Oh right, there are legal issues in Germany. And what about tenant electricity models?

That doesn’t work right now either. There are problems with billing.

It remains clear that the issue is not the generation of renewable energy, but rather bureaucracy in the country and its disastrous infrastructure.
A lot would be possible. However, that is not always in the interest of grid operators, energy companies, and politicians.

That is very pessimistic. Yes, real V2G (vehicle-to-grid) does not exist anywhere on a significant scale outside of research projects. This is understandable since an unpredictable energy supplier enters the market without integrating into the existing processes. This might not matter with five vehicles, but at larger numbers, they would disrupt the grid frequency. At the same time, this is only interesting for older contracts with high feed-in tariffs. For all others, it makes no difference or is even disadvantageous—otherwise, one could have just fed energy directly from the rooftop into the grid. This will only become relevant once dynamic tariffs for feed-in are available.

V2H (vehicle-to-home) is already commercially available, so far only as DC and at absurd prices, but from now until mid-2025, several AC wall boxes from well-known manufacturers are expected. These are V2G ready, but just as currently, feeding from the battery in the basement will not be permitted.

Tenant electricity has improved significantly with Solar Package 1? or 2? If this is relevant for you, it is not perfect yet but much better by far! Due to the mandatory installation of intelligent metering systems (IMS) and the allowance of virtual sum meters, only meters for end users, producers, and a single grid connection meter are necessary. So, one additional two-way meter more than otherwise required. Software allows arbitrary allocation settings, and at the same time, you no longer need to act as an energy supplier towards the tenants. Tenants keep their contracts with their chosen energy providers and pay you their share of the consumed photovoltaic electricity. You can set your selling price as you wish; taxation is somewhat special, but as a landlord, you would have to deal with it more than employees anyway.

@Fuchur This is also stated quite clearly in the letters from the Ministry of Finance: The counting is done per taxable entity or partnership. This means that for exemption, two independent systems up to 30kWp (kilowatt-peak) each are possible. I am curious how proof can be provided that these do not belong jointly to the spouses but separately to each. In most cases, this will probably fail anyway because the grid operator will be overwhelmed when asked about a 60kWp system.

Buchsbaum066 schrieb:

Since when did VW plan to equip its ID fleet with bidirectional charging capability?

This has been possible for a long time. What time period are you stuck in?

With the S10 E COMPACT home power station from Volkswagen partner E3/DC, you supply your home with solar energy and cover as much of your household consumption as possible with your photovoltaic system thanks to the Home Energy Management System (HEMS).
The system automatically controls the DC charging station to specifically use solar power for mobility, optimize self-sufficiency, and increase your safety during extended power outages. This ensures that your ID is charged primarily or exclusively with solar electricity. In addition, ID models with a suitable battery size of at least 77 kWh and ID software version 3.5 or higher from the factory can be integrated into the system as mobile energy storage. Even when energy is supplied back to your home, 20% of the battery capacity always remains in the vehicle.