IAB tax calculator
Liquidity and tax benefit under §7g EStG – year by year.
Model calculation – not tax or investment advice
This calculator provides a non-binding, simplified model calculation based on your inputs and documented assumptions. The results do not constitute tax, legal or investment advice and do not replace an individual review by your tax adviser. No warranty is given for accuracy or returns.
In three steps you see how an investment deduction allowance can affect your taxes.
- 01
Enter investment
Enter the planned net acquisition cost of your solar or storage system.
- 02
Add tax data
Provide your marginal tax rate, your profit, and the formation and acquisition years.
- 03
Read the effect
The calculator models the upfront deduction effect and the later add-back.
The calculator models the mechanics of the German investment deduction allowance under §7g EStG.
The investment deduction allowance lets you deduct up to 50 % of the expected acquisition cost as a profit reduction before the actual investment. Among other conditions, the profit in the formation year must not exceed the statutory limit of €200,000.
In the year of acquisition, the formed allowance is added back to profit. In addition, a special depreciation of up to 40 % may be claimed, while the regular straight-line depreciation of the PV system runs over 20 years.
The effect is primarily a liquidity and interest advantage: tax relief is brought forward in time but later balanced out. The actual amount depends on your individual circumstances.
The calculation is a simplified model and does not constitute tax advice.
For the IAB to apply, you need an investment that is actually delivered on schedule – which is exactly what we provide.
Turnkey system
We deliver solar and storage systems as a complete solution from a single source – the deductible investment the IAB builds on.
Predictable delivery
Realisation typically within 3–6 months, so the acquisition can be reliably booked in your planned investment year.
Experienced partner
Over 10 years of experience and more than 1,500 systems built give you confidence in your investment decision and timeline.
Development to operation
From project development and construction to operations management, we support your system across its entire lifecycle.
Let's talk about your project
From the first assessment to a turnkey plant – we support you across the entire value chain.