Photovoltaic systems & storage systems *collective thread*

I consider the claim of a 20-year lifespan to be misleading. My electric car has a Li-ion battery, which may last a long time, but the battery capacity decreases over time. At 75%, however, it is replaced free of charge. For other owners of this model, this was the case after about 4 to 5 years.
Is the provider's storage, which is also guaranteed for 20 years, regularly replaced free of charge? Or is only the lifespan guaranteed, but not the storage capacity?

When making the calculation decision, storage losses should also be taken into account. About 20-30% of the electricity used is lost when using storage. These are figures from users who complain in relevant forums that the storage (here, for example: [Nedap Power Router]) does not deliver the expected results. Such information, of course, is not found in the promotional brochure.
Therefore, one should inform oneself thoroughly beforehand to avoid a nasty surprise later.

Hello,

, everyone can apparently just put those things relatively unprotected in the basement today.

As far as I know, the batteries of the systems we have sold so far are currently not inside, but in front of the house.

Since there is such lively discussion here, I would like to recommend everyone to consult a professional – a recognized expert in photovoltaics and batteries. In my experience, that takes a good 2-3 hours, and since such a conversation is very technical, one conversation is not enough. Internet half-knowledge – especially with "newer" technology – is, in my opinion, a dangerous territory as well as a catch basin for "wannabe experts" who generalize from themselves to others.

Rhine greetings

Tonight we are going to another lecture by a construction company. We were already there last week for a different topic and today it's about "energy-efficient building." I'm curious whether storage systems like batteries will also be discussed, etc.
Regards, Andi

Does anyone have experience with storage systems / tax office and "not small business"?
Specifically: With my current photovoltaic system, I feed the surplus into the grid and consume about 20-25% as self-consumption.
The problem is: Three years ago, when I installed the system, the regulations regarding the taxation of self-consumption were still somewhat looser / less clear. That is why I chose "not small business."
According to my understanding, the new rule is: Self-consumption is considered a sale to the grid operator (= 19% VAT to be paid) + internal consumption by me as a private person - in other words, payment from private to business - thereby increasing the company's profit -> consequently higher tax amount that the company has to pay. The catch is: A sales/purchase price of 20 cents should be assumed. This makes the input tax / depreciation no longer worthwhile.
Now the specific question: How is it with storage systems? Is it also considered a sale/purchase there or is it treated differently?

From my layman's perspective, it is the same as with immediate self-consumption. Value-added tax must be paid on the self-consumption, and private withdrawals must be recorded in the profit and loss account = higher profit and higher taxes. However, the basis is not a flat rate of 20 cents. There is a current regulation that the price of the supplier must be used as the basis.

Roughly calculated: production costs + value-added tax portion (approx. 4 cents) + taxes on profit (cannot be that much) = price for the self-produced electricity.

I found something on the internet:
Interesting - the storage systems are apparently exempt from VAT and thus also from private withdrawals:

VAT for private photovoltaic self-consumption

The Federal Ministry of Finance has finally published a letter regulating the tax treatment of photovoltaic systems and battery storage.

The Federal Ministry of Finance has issued a long-awaited letter. It regulates the tax treatment of photovoltaic systems and battery storage.

This information is relevant for system operators who declare themselves subject to VAT in order to get the VAT paid at purchase refunded by the tax office. This is worthwhile in most cases and is therefore often practiced. The photovoltaic system thus becomes a business for tax purposes and privately consumed solar power must be taxed.

Until recently, the Federal Ministry of Finance (BMF) made clear statements only for systems that went into operation between 2009 and March 2012. These systems receive a remuneration for self-consumption and, for tax purposes, this electricity is to be fictitiously fed into the grid and simultaneously delivered back by the grid operator. (see explanation in the Federal Association of the Solar Industry's information sheet)

According to the latest BMF letter, this procedure should no longer apply to systems under the Renewable Energy Act that came into force in April 2012, because there is no longer a self-consumption remuneration for these systems. Instead, privately consumed electricity is recorded as “a free provision of services.” The assessment basis for this is the purchase price for electricity from the grid including the base fee.

Calculation example:

The system operator purchases electricity at a net price of 22 cents (excluding VAT) and pays a monthly net base fee of 5 euros. He receives 3,000 kilowatt hours (kWh) of electricity from the grid and consumes 1,000 kWh of solar power himself. The total electricity consumption is therefore 4,000 kWh. The purchased kilowatt hour thus costs 22 cents plus (5 euros x 12 months / 4,000 kWh =) 1.5 cents = 23.5 cents (net). For the self-consumed solar power, he accordingly pays 1,000 kWh x 0.235 euros x 0.19 (tax rate) = 44.65 euros VAT to the tax office*.

The BMF letter also provides a note on battery storage. If the battery is to be considered a “separate allocation object” for VAT purposes, input tax deduction is excluded if the storage is used only for private electricity consumption. This can be the case, for example, with retrofitted battery storage. If, on the other hand, the battery is part of a newly installed system, the input tax deduction should succeed. (Thomas Seltmann)

*) Note: In an earlier version of this article, the base fee was only related to the electricity purchase. According to the BMF, however, the corrected calculation shown here is correct. See also the supplementary article on the topic dated 29.10.2014.

Source: Photovoltaik-Magazine