Copernica Partners

Understand before you decide.

Direct investments are not an off-the-shelf product. In this collection we explain the tax, technical and economic levers in detail, so that you, as an investor, can evaluate each position independently.

These articles do not constitute tax or legal advice. Tax and legal effects depend on your individual situation. Please discuss any concrete structure with your own tax advisor.

New articles regularly

Articles.

Tax & structuring07 Sept 2026

The loss created by an investment deduction (IAB): offsetting it against salary, carrying it back and carrying it forward

An investment deduction does not lower your tax bill directly; it lowers the profit of a business, usually far enough to turn it into a loss. What happens to that loss decides the real tax effect: it is offset against the salary or practice profit of the same year, carried back into the previous year, or carried forward into later years. Each stage has its own limits, and the most expensive one is not written in §10d EStG but in the tax tariff.

~10 min readRead
Practice & process06 Sept 2026

Reading a yield assessment: what P50 and P90 mean for a solar park direct investment

Every financial model for a solar park rests on a single number: the kilowatt-hours the plant delivers per year. Where that number comes from is set out in the yield assessment, and there it does not appear once but as P50, P75 or P90. Anyone who can read those labels can tell whether a return forecast rests on the expected value, on a safety margin or on wishful thinking.

~10 min readRead
Markets & technology02 Sept 2026

Data centres and AI: what the new electricity demand means for solar and storage investors

Data centres are widely described as the big new electricity consumer, with artificial intelligence as the driver behind them. For investors in solar parks and battery storage the question is narrower: does any of that demand reach the revenue side? The figures are public; depending on the source, they differ by a factor of several.

~10 min readRead
Tax & structuring01 Sept 2026

Tax audits and the investment deduction amount: what the tax office actually checks

Anyone using the Investitionsabzugsbetrag (IAB) for the first time sooner or later expects a letter from the tax office. The concern is understandable, but the procedure behind it is neither opaque nor open-ended: who may be audited, how a field audit runs and what has to be produced is set out in detail in the Abgabenordnung. New rules have applied since 2025, and the first cohort fully covered by them is precisely the one in which many investors formed their IAB.

~11 min readRead
Tax & structuring31 Aug 2026

Trade tax on PV and storage direct investments: how much of it actually sticks

Anyone reading for the first time that a direct investment constitutes a commercial business expects a second tax on top of income tax. The worry is understandable and, in most cases, unfounded: the tax-free allowance, the loss-making early years and the credit under §35 EStG mean that for individuals, little of the trade tax ever sticks. The more interesting question is where it goes when it does arise: nine tenths of it to the municipality where the plant stands.

~9 min readRead
Practice & process30 Aug 2026

Grid connection, easement, building rights: how to tell whether a direct investment has truly secured its site

Before anyone talks about returns and tax leverage, three unglamorous legal positions decide whether a project can exist at all: the right to stand on the land, the right to build there, and the connection that carries the power into the grid. All three can be evidenced with documents, and all three tend to get compressed into a single line in sales material. This article explains how site security, building rights and grid connection work, and how to tell from the data room whether they hold.

~10 min readRead
Practice & process27 Aug 2026

Insuring a solar park or battery storage asset: which policies belong to a direct investment, and who holds them

What happens if the park burns down or a hailstorm destroys the modules? The physical damage is the smaller problem, because it is insurable and is routinely insured. It gets expensive where a policy exists but pays only in part, and where the tax office treats the payout as profit. This article explains the four covers, the typical gaps and the questions to ask before you sign.

~10 min readRead
Tax & structuring26 Aug 2026

Passing on a direct investment: how German inheritance tax favours business assets

A direct investment does not only cut your tax bill on the way in; it is also privileged when it passes to the next generation. As business assets, it can be 85 or even 100 percent exempt from German inheritance and gift tax under §§13a, 13b ErbStG, on top of the personal allowances. This article explains how the exemption works, which obligations the successor takes on, and what happens to the IAB and special depreciation in the event of inheritance.

~9 min readRead
Practice & process24 Aug 2026

Provider or operator insolvency: what happens to your direct investment

No serious review of a direct investment gets past the question: what actually happens if the provider goes bust? The answer depends less on the fate of individual companies than on the structure: who owns the plant, who holds the site rights, and how replaceable the service providers are. This article walks through the scenarios one by one, from the developer during construction to the technical operator, the power marketer and the land lease, and shows what an insolvency-resilient structure looks like.

~9 min readRead
Markets & technology23 Aug 2026

A solar park after 20 years: continued operation, repowering or decommissioning?

The 20 years of EEG remuneration are the best-known date in the life of a solar park, but not its end. The modules keep producing, the grid connection keeps its value, and what becomes of the site is decided by the land lease. This article sorts out the four different lifetimes of an energy direct investment, walks through the three paths at the end of the subsidy period and explains how residual value and decommissioning costs belong in an honest return calculation.

~10 min readRead
Tax & structuring22 Aug 2026

Saving tax as a freelancer or self-employed professional: the §7g lever alongside your own practice

High-earning IT freelancers, engineers, consultants and architects pay tax on their full profit immediately and without an employer buffer; the top rate starts at roughly €68,000. The investment deduction is open to the self-employed, but their own business usually has nothing worth using it on. This article shows why an energy direct investment as a business of its own makes the lever work, how the relief arrives through advance payments in the current year, and what changes for VAT, trade registration and bookkeeping.

~10 min readRead
Markets & technology19 Aug 2026

Direct marketing and the market premium: how a solar park earns its money

A modern solar park does not receive a fixed feed-in tariff. It sells its electricity on the power exchange through a direct marketer, and the EEG support is paid on top as a sliding market premium. How the model works, where the award value comes from, and what the direct marketer charges for its role.

~9 min readRead
Markets & technology18 Aug 2026

Grid fees for battery storage: the exemption until 2029 and the AgNeS reform

Battery storage systems are exempt from grid fees for up to 20 years; that very rule is being rewritten right now. What Section 118 EnWG regulates, what the final draft of Germany's grid fee reform changes, which projects keep their grandfathered status, and what all this means for storage revenues.

~9 min readRead
Markets & technology17 Aug 2026

How does a grid-scale battery storage system work? Design, operation and revenue logic explained

Battery containers, inverters, a grid connection: those are the building blocks of a storage power plant. How the asset behind a direct investment absorbs, stores and resells electricity, explained without jargon.

~8 min readRead
Markets & technology16 Aug 2026

Understanding PPAs: how power purchase agreements make solar park revenues predictable

What the acronym PPA stands for, how a long-term power purchase agreement forms the revenue floor of a solar park, and where its limits lie.

~9 min readRead
Tax & structuring14 Aug 2026

VAT on PV and storage direct investments: why 19% is charged here, and how it flows back

Rooftop solar on the family home has enjoyed a zero VAT rate since 2023, and many investors mentally extend that to every PV investment. For a direct investment in a ground-mounted plant or a large-scale battery storage system it does not hold: here, 19% VAT is charged on the purchase price. The money is not lost; it flows back as input VAT, provided the small-business scheme and the filing routine are set up correctly.

~10 min readRead
Practice & process13 Aug 2026

Selling a direct investment early: how liquid an energy direct investment really is

A direct investment in a battery storage system or a ground-mounted solar plant ties up capital for ten years and more. The question of what happens if you need the money sooner comes up in almost every first call, and usually only at the end. Selling is possible; it takes a buyer, the bank's consent and the right moment. Where that moment lies, and which deadline actually matters, can be answered more precisely than the common rules of thumb suggest.

~10 min readRead
Markets & technology11 Aug 2026

Negative electricity prices: what they mean for solar and storage investors

In 2025, the German exchange price for electricity was negative in 573 hours, more often than ever before, and 2026 is set to break that record again. For solar parks these hours are a revenue risk; for battery storage they are a source of income. A sober look at both sides.

~8 min readRead
Tax & structuring10 Aug 2026

Saving tax as a high-earning employee: the §7g lever alongside your salary

Employees earning €150,000 and more pay between 42 and 47.5 % tax on every additional euro, withheld monthly, and the usual tax tips change little about that. This article shows why the strongest lever in German tax law requires a business of your own, how an energy direct investment establishes that business, and how the relief arrives against your salary.

~10 min readRead
Tax & structuring09 Aug 2026

Saving tax as a business owner or managing director: the §7g lever alongside your company

Sole proprietors, partners and owner-managers pay between 42 and 48 % tax on every additional euro that is meant to arrive privately; and the strongest investment lever in German tax law is blocked inside their own company once profit exceeds €200,000. This article shows why an energy direct investment as a business of its own brings its own profit cap, when the private route beats the GmbH route, and what the numbers look like.

~10 min readRead
Tax & structuring08 Aug 2026

Saving tax as a lawyer or law-firm partner: the §7g lever alongside the firm

Law-firm partners and self-employed lawyers pay up to 47.5 % tax on every additional euro of their profit share, and the strongest investment lever in German tax law is often blocked by the profit cap of their own firm. This article shows why an energy direct investment, held as a business of its own, starts exactly there, which infection trap partnerships must know, and what the numbers look like.

~10 min readRead
Tax & structuring07 Aug 2026

The Investitionsabzugsbetrag explained simply: how the IAB works

The Investitionsabzugsbetrag (IAB, Germany's investment deduction) lets you deduct up to 50 % of a planned investment from your taxable profit before you buy. This article explains the mechanics from scratch: no tax knowledge required, step by step, with a deliberately simple worked example. As of August 2026.

~8 min readRead
Tax & structuring05 Aug 2026

Liebhaberei and profit intention: when the tax office cancels the tax lever

Investment deduction, special depreciation, declining-balance depreciation: all three rest on something almost no guide mentions, namely a business the tax office actually recognises as a business. Without profit intention (Gewinnerzielungsabsicht), the entire lever falls away retroactively. This article explains how the total-profit forecast works, how long start-up losses are harmless, and why §15b EStG is the second and far less frequently named trap.

~10 min readRead
Tax & structuring04 Aug 2026

Deducting photovoltaics from tax: when depreciation and the §7g deduction still work

Since 2022 small rooftop systems have been tax-exempt, and that is precisely why nothing can be deducted for them any more. Which systems the exemption under §3 no. 72 EStG covers, why it costs the depreciation lever, and from what size straight-line depreciation, special depreciation and the investment deduction apply again.

~9 min readRead
Tax & structuring03 Aug 2026

Saving tax as a physician or dentist: the §7g lever alongside the practice

Physicians and dentists in private practice pay up to 44.3 % tax on every additional euro, and the strongest investment lever in German tax law is often blocked by the profit cap of their own practice. This article shows why an energy direct investment, held as a business of its own, starts exactly there, which infection trap group practices must know, and what the numbers look like.

~10 min readRead
Basics02 Aug 2026

Solar or fixed-term deposit? Interest account and real asset in an honest comparison

The best fixed-term deposit accounts pay around 2.8 % per year in August 2026; inflation stood at exactly 2.8 % in July. Before taxes, savings are treading water; after the flat-rate capital gains tax, they shrink in real terms. This article works through honestly what the interest account delivers, where it remains irreplaceable and at what point an energy direct investment becomes the better answer for capital that is tied up long term anyway.

~9 min readRead
Practice & process31 Jul 2026

Financing a direct investment: bank loan, KfW 270 and the pitfalls

Energy direct investments are rarely paid for entirely out of equity: project-typically, bank financing carries 60 to 75% of the investment. This article explains how financing works in a direct investment, what Germany's KfW 270 promotional loan offers, the sequence the application has to follow, and which pitfalls can cost you the subsidy or the tax concept.

~9 min readRead
Basics29 Jul 2026

Solar or ETF? Real asset and portfolio in an honest comparison

A broadly diversified ETF portfolio is the right core of most investors' wealth; cheap, liquid, spread across more than a thousand holdings. But anyone paying tax on a high income runs into two limits that no savings rate can solve: a contribution to the portfolio reduces the tax bill by exactly nothing, and everything in the portfolio hangs on the same markets. This article compares a securities portfolio and an energy direct investment honestly, including the points where the ETF is clearly ahead.

~9 min readRead
Basics28 Jul 2026

Investing in solar parks: revenues, costs and tax leverage at a glance

Ground-mounted solar parks now carry the largest share of Germany's photovoltaic build-out, and they have long become an asset class in their own right. This overview sets out how a solar park makes money, what it costs, which routes in exist and which tax lever applies.

~9 min readRead
Tax & structuring27 Jul 2026

Invest through your GmbH or privately? The honest tax comparison

Roughly 30 % tax on profits inside a GmbH, up to 47.5 % privately, and a 26.375 % distribution tax in between: where an investment belongs for tax purposes depends less on the investment itself than on where the capital sits and where it is ultimately needed. This article compares both routes honestly, including the question of whether a GmbH can subscribe to a §7g investment itself.

~9 min readRead
Basics26 Jul 2026

Solar or property as an investment: an honest comparison of two real assets

The rented flat was Germany's default capital investment for decades. Anyone running the numbers in 2026 sees tighter rental yields, high transaction costs and growing regulatory burdens; at the same time, the direct investment in energy infrastructure has emerged as a second real asset. This article compares the two honestly: yield ranges, taxes, effort, inflation linkage and risk.

~9 min readRead
Tax & structuring25 Jul 2026

Selling a practice or business: optimising the tax and reinvesting the proceeds sensibly

Selling a medical practice, a law or tax firm, or a business turns decades of work into cash within a single tax year; the tax on it is correspondingly high if left to chance. This article ranks the allowance, the fifth rule and the reduced rate, and shows how a reinvestment with an investment deduction lowers the tax in the year of sale even further.

~9 min readRead
Basics24 Jul 2026

Real assets as inflation protection: what actually protects and where energy assets fit in

Savings in a call-money account lose real value as soon as the interest rate sits below inflation. Real assets are held up as the antidote, yet not every real asset protects equally well. This overview sets out what separates real assets from monetary assets, which asset classes exist and where energy assets fit in.

~8 min readRead
Markets & technology22 Jul 2026

The battery as a real asset: lifespan, degradation and warranties of a grid-scale storage system

Behind every participation stands a physical battery whose cell chemistry, cycle life, degradation and warranties determine the return and risk of the next 15 to 20 years. What investors should know about the technology, translated into return, risk and the questions to ask, not a spec sheet. As of July 2026.

~10 min readRead
Tax & structuring20 Jul 2026

After the IAB: How the ongoing returns and the sale of a direct investment are taxed

The IAB cuts your tax in year one; that is the loud half of the story. The quiet half comes later: how are the ongoing returns taxed, and what happens on the tax side when the investment is sold at the end of the term? Because a direct investment is commercial in nature, both follow a different logic than interest or dividends. A factual overview of the tax picture after the IAB.

~8 min readRead
Tax & structuring19 Jul 2026

Investing a severance payment tax-efficiently: the fifth rule, the IAB and the energy investment

A severance payment lands on top of your other income as a one-off, and is therefore taxed almost entirely at the top rate. This article ranks the legal levers for reducing the tax on it, and shows why the investment deduction moves far more than the fifth rule alone for high earners.

~9 min readRead
Practice & process18 Jul 2026

Direct investment or closed-end fund? The structural comparison

Both routes invest you in real energy assets, but through fundamentally different structures. The difference decides the tax lever, costs, control and regulation. A factual comparison.

~8 min readRead
Practice & process18 Jul 2026

From first enquiry to closing: how a direct investment works step by step

Between 'interested' and 'invested' lie several steps: first call, project selection, documents, subscription, financing, closing. This article walks through the process step by step and what to check at each stage.

~8 min readRead
Basics18 Jul 2026

Investing in agrivoltaics: dual land use, revenues and tax leverage at a glance

Agrivoltaics lets the same land carry both crops and solar power, and has become an asset class in its own right. This overview sets out how agri-PV works, how you get in and which tax lever applies.

~8 min readRead
Tax & structuring16 Jul 2026

Forming the IAB now: which tax deadlines and time windows count in 2026/2027

Anyone considering a battery-storage direct participation is not making one decision but four, and each has a date: form the IAB in the right tax year, invest within three years, secure the declining-balance depreciation only through the end of 2027, tie the grid-fee exemption to commissioning. The investor's tax and project calendar, with an honest section on what argues against rushing. As of July 2026.

~9 min readRead
Tax & structuring15 Jul 2026

The IAB in your German tax return: where and how to actually claim it

Anlage EÜR, E-Bilanz or the partnership's tax return: Depending on your setup, the investment deduction (IAB) is claimed in different places, and always electronically. Where exactly it goes, which deadlines apply, and what runs differently for a co-investment via a GbR. As of July 2026.

~9 min readRead
Tax & structuring14 Jul 2026

Reversing the IAB: what happens if you don't invest, deadlines, interest, ways out

If you claim an investment deduction (IAB) and never invest, the tax comes back retroactively, with 1.8% annual interest running from 15 months after the deduction year. How the reversal under §7g (3) and (4) EStG works, what it costs in euros, and which ways out the law leaves. As of July 2026.

~9 min readRead
Markets & technology13 Jul 2026

Germany's battery storage market: the numbers, the drivers, and why "now" has a date

Record buildout, 573 hours of negative power prices, a 700 GW grid-connection queue, and regulatory deadlines that sit closer than 2029. A sober stocktake of the German storage market, as of mid-2026.

~8 min readRead
Tax & structuring11 Jul 2026

Investitionsabzugsbetrag: all §7g EStG requirements, and who can use it

Profit ceiling, eligible assets, deadlines, reversal. And the question most guides leave open: how employees create their own access to the IAB, by founding a business or through a commercial partnership investment. As of July 2026.

~9 min readRead
Markets & technology07 Jul 2026

Co-located vs. stand-alone: which gives the better risk structure

When a PV-plus-storage hybrid beats a stand-alone battery, and when it doesn't. A factual comparison of both structures.

~7 min readRead
Markets & technology03 Jul 2026

Direct marketing explained: day-ahead, intraday and balancing power

How a modern battery storage system earns money, and why three parallel revenue streams structurally reduce market-price risk.

~10 min readRead
Practice & process01 Jul 2026

Risks in BESS direct investments, and how they are structurally addressed

Power-price risk, technology, financing, regulation. An honest assessment of the four main risks of a direct investment in battery storage, and the typical mitigants.

~10 min readRead
Markets & technology24 Jun 2026

Battery storage returns: where the revenue comes from, and what is realistic

Grid-scale battery storage is regarded as a high-return real asset. But where does the return actually come from, how high is it realistically, and why is it a range rather than a fixed number? This article sets out the revenue sources, the orders of magnitude and the tax lever.

~9 min readRead
Basics16 Jun 2026

Investing in battery storage: the options at a glance

Battery storage is one of the most compelling infrastructure assets of the energy transition. But 'investing' is not one thing: there are four fundamentally different ways in, from the share to the entrepreneurial direct investment. This overview puts them in order.

~6 min readRead
Tax & structuring15 Jun 2026

Sonder-AfA §7g (5) vs. declining-balance AfA §7 (2): which combination, when?

Since the 2025 Investitionssofortprogramm, declining-balance AfA is back at up to 30 %, alongside the Sonder-AfA under §7g. Why the two together produce the largest tax effect in year one, for battery storage and solar PV alike, and why that early liquidity is the real lever.

~7 min readRead
Tax & structuring13 Jun 2026

Legally reducing your tax: the most effective strategies

Most 'tax tips' move a few hundred euros. For high earners, the self-employed and business owners, a different league of levers applies. This article ranks the legal strategies by actual impact.

~9 min readRead
Practice & process11 Jun 2026

How much equity is actually required?

Why the common rule of thumb 'from €200,000 equity' is misleading, and how tax refunds and project debt push the effective equity outlay into the single-digit-percent range.

~5 min readRead
Tax & structuring09 Jun 2026

Using the investment deduction every year: building a portfolio over multiple years

The investment deduction under §7g EStG is not a one-off trick but an annual instrument. Those who understand this build a diversified portfolio of energy direct investments over several years, with a recurring tax effect instead of a single one.

~8 min readRead
Practice & process07 Jun 2026

What happens after closing: reporting, asset management and why a partner is not a broker

Most problems with a direct investment arise not at the purchase but in the 20 to 30 years that follow. This article shows what actually has to be done after closing, and why it matters whether your provider is still reachable afterwards.

~7 min readRead
Practice & process05 Jun 2026

Transparent costs: which fees a direct investment involves, and which ones are hidden

A direct investment has no standardised fact sheet; the provider sets the cost structure. This article names every fee that should arise in the open and shows the hidden cost patterns you have to ask about actively.

~6 min readRead
Practice & process01 Jun 2026

How to tell a trustworthy provider of energy direct investments

With a direct investment in an energy asset, you hand a six-figure sum to a provider before a single kilowatt-hour has been sold. This article shows the seven warning signs that point to trouble in practice, and the questions you can use to test any provider, including us.

~7 min readRead
Tax & structuring28 May 2026

IAB under §7g EStG: example calculation for battery storage

How the Investitionsabzugsbetrag under §7g EStG actually affects a €300,000 direct investment in a battery storage system: step by step, with real numbers, and with the pitfalls most often overlooked in practice.

~8 min readRead

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