PV & real estate in 2026: How entrepreneurs use the new depreciation rules effectively

In 2026, a PV system on the roof of an office building isn't just an energy question – it's one of the few remaining tax niches where significant savings can be unlocked in the short term. But the rules have grown complex, and the difference between a good and a very good setup can easily run to €50,000–€150,000 per property.

The 2026 rules at a glance

• Special depreciation of up to 50% in the year of acquisition for PV systems on rented commercial property (§ 7g EStG, broadened scope).
• Declining-balance depreciation of up to 6% p.a. on top of the linear 4% – for all residential buildings completed after 31.12.2025.
• Investment deduction (IAB) of up to 50% of expected acquisition costs – plannable up to three years before purchase.
• Extended subsidy period for energy-related refurbishments under § 35c EStG until 2030 – with broader subsidy rates.

It sounds complex – and it is. But the levers are so large that the effort almost always pays off. Three typical scenarios from our client base follow.

Scenario 1: Your own warehouse with rooftop PV

One of our clients – a maker of premium furniture – installs a 380 kWp PV system on the roof of their production GmbH. Acquisition cost: €420,000. Self-consumption ratio: 70%, with the rest exported to the grid.

Tax-wise something elegant happens here: through the investment deduction we were able to deduct €210,000 in the previous year (50% of expected cost). In the year of commissioning, the special depreciation kicks in for another €105,000. Linear depreciation then runs over the remaining book values. Effective tax relief in the first two years: around €95,000 at a 30% trade-tax-level burden.

Free initial analysis

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Scenario 2: Rented residential building with energy refurbishment

A second typical case: a multi-family rental building from the 1970s. The owner switches to a heat pump, insulates the façade and adds a smaller 18 kWp PV system. Total investment: around €280,000.

Tax-wise, several rules interlock here: the refurbishment costs aren't fully deductible in year one, but depreciated linearly at 4% plus up to 6% declining-balance. The PV system is generally treated separately – with the special depreciation option. And § 35c EStG allows for an additional direct tax credit of 20% of the refurbishment costs, spread over three years.

What matters is the order of claims: claiming the § 35c subsidy first prevents you from double-using the same expenses later. For our client, the correctly structured advantage came to roughly €78,000 over ten years.

Scenario 3: PV inside an asset-holding GmbH

It gets interesting when clients with a holding structure plan a larger installation and have to decide whether the PV should run in a separate operating GmbH or directly in the asset-holding GmbH.

• Asset-holding GmbH: lower effective burden (~15% rather than 30%), but strict requirements – beyond a certain activity threshold the GmbH is re-qualified as commercial. The advantage is lost and new risks appear.
• Separate operating GmbH: higher ongoing burden, but maximum flexibility for distributing profits to the holding (95% tax-free) and cleanly separated in a sale scenario.
• Asset-managing partnership: in some configurations the best solution – but only if trade tax doesn't apply and the personal income tax lever bites at the shareholder level.

Which variant is right depends on the system size, self-consumption ratio, the company's other activities and the overall strategy. Three clients – three different answers in the past six months.

Pre-investment checklist

1. 1Lock in the legal owner: who owns the property, who buys the PV system, who sells the electricity?
2. 2Estimate the self-consumption ratio: above or below 50% determines the tax treatment.
3. 3Check the investment deduction: with timely planning, 50% can be deducted upfront.
4. 4Combine special and declining-balance depreciation correctly – don't claim the same costs twice.
5. 5Run § 35c EStG against AfA when the property is owner-occupied.
6. 6Clarify with the house bank: subsidised loans (KfW 270, IBB) reshape the cash-flow story dramatically.

Bottom line

PV in 2026 is no longer just an energy topic – it has become a tax-planning playground with significant levers. Those who plan early, pick the right elections and draw clean boundaries get a markedly better result out of the same investment. Those who don't leave a substantial part of the economics on the table.