Photovoltaics as an Investment: Comparing ETFs, Real Estate, and Money Market Accounts
Excerpt
As an investment, photovoltaics offers a profile in 2026—with returns of 6–10%, legally guaranteed income, and unique tax benefits—that traditional investment forms cannot replicate; however, to be honest, it also has clear limitations. This article directly compares PV with ETFs, real estate, and money market accounts using concrete figures from March 2026: returns, inflation, taxes, and real risks.
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ETFs yield 9.7% per year over the long term, but with fluctuations of up to –57% in market crash years. In major cities, real estate now yields only a 1.5–2.5% net return, with construction interest rates of 3.5–4.0%. Money market accounts currently pay an average of 1.5%—less than the inflation rate of 2.1% (January 2026). As an investment, solar power ranks in the upper mid-range at 6–10% per year, combining a tangible asset with predictable returns and offering tax advantages that no other asset class can match. Every type of investment has its place—the question is which profile suits which investor.
Table of Contents
1. The Background: Why the 2026 Comparison Is Relevant
Preserving and growing capital is no easy task in 2026. The ECB has lowered its deposit rate from 4.00% to 2.00% since June 2024—effectively halving interest rates on savings. The inflation rate in Germany stands at 2.1% (Destatis, January 2026), and the Bundesbank forecasts around 2.0–2.2% for the full year 2026. In this environment, deposit products are losing value in real terms due to inflation, while alternatives in tangible assets are increasingly in demand.
At the same time, the PV market environment has undergone fundamental changes: System prices for turnkey commercial installations are at historic lows of around €1,015/kWp; lawmakers have created new depreciation options through the Growth Opportunities Act and the Immediate Investment Program; and the planned 2027 EEG reform is creating concrete pressure to act for all those who still wish to invest under the existing feed-in tariff system.
2. Direct Comparison of Returns – Four Asset Classes, Real Numbers
Call money and time deposits: The best call money offers in March 2026 pay up to 3.40% (Biallo Index, Verivox), while the market average is only 1.50%. One-year time deposits from top providers yield 2.60–2.80%. After deducting withholding tax (26.375%) and inflation , the average call deposit customer is left with a negative real return of –0.4%. Even with the best fixed-term deposit offer, the real return after taxes and inflation is just +0.16%. (Source: Verivox, Biallo, Destatis, March 2026)
ETFs: Broadly diversified index funds are the most profitable liquid asset class over the long term. The MSCI World has delivered an average annual return of 9.7% since 1975, while the S&P 500 has averaged 10.3% annually since 1928. The year 2024 was exceptionally strong: MSCI World +26% in euros, DAX +19%. 2025 was more moderate: MSCI World +7.9% in euros, S&P 500 +17.9% in USD. Costs are minimal—leading ETFs have a TER of 0.05–0.20%. The downside: During the 2008–09 crash, the MSCI World lost up to –57% from peak to trough (calendar year loss in 2008: approx. –42%), and the recovery took years. Anyone who sold at an inopportune time in 2008 or 2022 realized real losses. (Source: Finanztip, Zendepot, ExtraETF, March 2026)
Real Estate: This traditional investment in tangible assets presents a mixed picture in 2026. Gross rental yields in A-class cities range from 3.0% to 3.3% (Munich 3.08%, Berlin 3.06%, Hamburg 3.02%), while in some B/C-class cities they reach 5.5% to 5.9% (Chemnitz). Net—after management fees (5–10% of rental income), maintenance (€7–12/m²/year), and the risk of rent loss—only 1.5–2.5% remains in major cities . With construction interest rates currently at 3.5–4.0% for a 10-year fixed-rate period (Finanztip, March 2026), rental income alone generates virtually no positive cash flow. Residential real estate prices have rebounded since Q4 2024 following the decline in 2022–2024: In Q1 2025, they rose by +3.8% compared to the previous year. (Source: Federal Statistical Office, MyInvest24, Schwäbisch Hall, 2025)
Photovoltaics as an investment: Commercial rooftop and ground-mounted systems yield 6–10% per year before taxes over a typical operating lifespan of 20–40 years (Helm Group, portfolio data for 2024). Residential rooftop systems yield 3.5–8%, depending on the self-consumption rate and use of storage. The key factor in self-consumption: Every kilowatt-hour consumed on-site replaces grid electricity at around 35 ct/kWh instead of the feed-in tariff of 7.78 ct/kWh— four times as much. Furthermore, returns are not correlated with stock markets or economic cycles: the sun rises regardless of stock prices. Our article on solar system returns in 2026 for commerce and industry explains in detail how the return structure of commercial PV systems is constructed.
Yield Comparison 2026
Four asset classes · Typical annual return · Germany
Source: Finanztip, Biallo, Helm Group (portfolio data for 2024), MyInvest24, Federal Network Agency · As of March 2026 · All information is provided without warranty · This is not investment advice
3. Tax Benefits: Where Photovoltaics Stands in a League of Its Own as an Investment
Tax optimization is one of the strongest arguments in favor of PV as an investment—and yet it is also the most frequently underestimated.
Call money: Withholding tax of 26.375% on all income exceeding the saver’s allowance (€1,000/€2,000 for married couples). No options for tax planning.
ETFs: Also subject to withholding tax, but with a 30% partial exemption for equity ETFs—effective tax rate 18.46%. Upfront flat-rate tax on reinvesting ETFs (base rate for 2026: 3.20%). Overall, fair and transparent, but offers little room for tax planning.
Real Estate: Significantly greater leverage. New buildings completed on or after 2023 will be depreciated on a straight-line basis at a rate of 3% (over 33 years). The 2024 Growth Opportunities Act also introduced a 5% declining balance depreciation rate for new rental residential buildings (construction start dates: October 1, 2023–September 30, 2029; no separate energy efficiency requirements). Interest on debt and administrative costs are deductible as income-related expenses, and losses can be offset against income. The biggest advantage: After a 10-year holding period, the capital gain is completely tax-free.
Solar power systems offer the most comprehensive range of tax incentives—for taxable systems over 30 kWp:
Investment deduction (IAB, Section 7g of the Income Tax Act): Deduct 50% of the planned investment costs from taxable income in the previous year, up to a maximum of €200,000 per business
Special depreciation (Section 7g(5) of the Income Tax Act): An additional 40% in the first five years since the passage of the Growth Opportunities Act of 2024
Declining-balance depreciation: Since the launch of the Immediate Investment Program in July 2025, 15% of the remaining book value per year (valid through December 31, 2027)
Tax exemption (Section 3(72) of the Income Tax Act): Systems up to 30 kWp are fully exempt from income tax—plus 0% sales tax on the purchase
With a €100,000 investment and a marginal tax rate of 42%, the combination of the IAB and special depreciation results in tax savings of over €30,000 over two years —a benefit that no other asset class offers in this way. Our article on photovoltaics and tax savings provides the detailed calculation.
(Source: § 7g of the Income Tax Act (EStG), Haufe, Federal Law Gazette I 2024 No. 108, Federal Law Gazette 2025 I No. 161)
4. Predictability and Liquidity – The Underestimated Factor
Predictability and liquidity are two sides of the same coin—and no single asset class excels at both at the same time.
ETFs are the most liquid investment vehicle: they can be traded within seconds, and proceeds are credited to your account on T+2. However, returns are entirely variable—if you need capital during a market crash, you’ll have to take a loss.
Call money combines daily liquidity with nominal value stability. Time deposits are locked in for the term of the deposit. Both are protected by deposit insurance up to €100,000 per bank. With time deposits, returns are predictable, but with call money, they are variable and entirely dependent on interest rates.
Real estate is the least liquid asset class: properties typically take 3–6 months to sell, and over a year in less desirable locations. Rental income is relatively stable, but there is no legally mandated minimum guarantee. Rent control, renovation obligations, and GEG requirements further restrict the owner’s freedom.
PV systems are the only asset class with legally guaranteed minimum returns: The EEG feed-in tariff is set at the time of commissioning and remains in effect for 20 years. Current feed-in rates: 12.73 ct/kWh for full feed-in and 7.78 ct/kWh for partial feed-in for rooftop systems up to 10 kWp (February–July 2026, source: Federal Network Agency). Liquidity is limited—selling a system is possible, but it is not a standardized process. A PV investment is a long-term model with a 20–40-year lifespan, not a short-term parking spot for capital.
An important date: The planned 2027 EEG reform calls for the introduction of two-way contracts for difference (CfDs) for new installations, under which excess profits will be returned to the government. Anyone still investing under the current system—with asymmetric upward participation—must ensure that the plant is commissioned before July 17, 2027. Our article on the CfD requirement for PV investors starting in 2027 explains what this reform means in concrete terms.
5. Risks clearly identified: PV is not a risk-free investment
Every asset class has its Achilles' heel—including private equity.
ETF Risks:
Market risk: Peak-to-trough loss of up to –57% (MSCI World 2007–2009); calendar-year loss in 2008 of approximately –42%
Currency risk: A 70% allocation to U.S. stocks in the MSCI World Index implies dependence on the EUR/USD exchange rate
Concentration risk: The top 10 stocks account for over 20% of the index
No capital protection: real losses are possible if the timing is wrong
Real Estate Risks:
Concentration risk: A single property concentrates assets in a specific region
Regulatory risk: rent control, GEG Heating Act, EU renovation requirements by 2030/2033
Vacancy rate: 2.2% nationwide, 6.9% in regions experiencing population decline (empirica regio, 2025)
High transaction costs: 9–13% in closing costs, 3.5–6.5% in real estate transfer tax
Risks associated with overnight money:
Inflation risk: persistently negative real returns
Interest rate risk: ECB decisions take effect immediately
Opportunity cost: 3–5 percentage points lower per year than ETFs over a 10-year period
PV Risks:
Regulatory risk: 2027 EEG Reform (mandatory CfDs, end of fixed feed-in tariffs for new installations)
Market price risk in direct sales: The market value of solar power fluctuated between 2.0 ct/kWh (May) and 11.0 ct/kWh (January 2026) in 2025
Technical risk: Inverter lifespan 10–15 years; replacement cost €1,500–3,000
Revenue risk due to negative electricity prices: In 2025, there were 575 hours with negative spot market prices—since March 2025, feed-in tariffs have been suspended during these periods (Solar Peak Act)
Partner risk: The quality of the project developer and operator over a period of 20+ years is the key due diligence issue
6. Protection against inflation: Which investment holds its value?
With an inflation rate of 2.1% (January 2026, Destatis) and a forecast of 2.0–2.2% for 2026 (Bundesbank), preserving capital in real terms is by no means a given.
ETFs offer the strongest protection against inflation over the long term: Companies can pass on cost increases through price hikes, and the historical real return is 5–7% per year after inflation. In the short term, interest rate hikes aimed at combating inflation—such as those in 2022—can put downward pressure on prices.
Real estate provides direct protection through index-linked rents: Rent can be tied to the consumer price index. Rents for new leases rose by about 5.3% in 2025. However, the real long-term appreciation of German real estate is only 0–2% per year —significantly less than is often assumed.
Money market accounts offer no protection against inflation—their nominal value remains stable, but their purchasing power declines.
PV systems offer mixed protection: The EEG feed-in tariff is nominally fixed for 20 years but loses value in real terms due to inflation. In contrast, self-consumption benefits from rising electricity prices: Given a historical annual increase of around 2–3% in grid electricity prices, today’s commercial electricity price of 35 ct/kWh would be around 43–45 ct/kWh in ten years—making every kWh consumed on-site more valuable. With direct marketing, revenues also rise in line with wholesale prices.
7. Which asset class is right for whom?
The question isn't which asset class is the "best"—but which one suits the investor's profile.
An emergency fund is best suited as a liquidity reserve and safety net, not as a standalone investment strategy. Recommended amount: 3–6 months' salary.
ETFs are the right choice for long-term wealth accumulation with a time horizon of 15 years or more, full liquidity, and low management costs. Minimum investment: starting at 1 euro.
Real estate can be a sound investment if you purchase properties wisely in high-growth regions, plan to hold them for the long term (over 10 years) to benefit from tax-free capital gains, and are willing to actively manage the properties. Realistic minimum capital investment: €25,000–€90,000 in equity plus closing costs.
Photovoltaics as an investment is particularly attractive for:
Business owners and self-employed individuals with a marginal tax rate of 42% or higher who can take full advantage of the IAB and special depreciation allowances
Companies looking to structurally reduce their electricity costs—this is where self-consumption has the greatest impact
Investors with a 20+-year investment horizon who prefer predictable cash flows over price fluctuations
Portfolio investors seeking diversification through a source of return that is not correlated with stock markets
Consider photovoltaics as an investment
A no-obligation initial consultation with a specialized financial advisor from our network of partners · mediplan Helm e.K. is personally liable
Request an initial consultation Learn more about the investment model →For companies looking to own their own facility without a large upfront capital investment, the PV model requiring no equity is a sensible way to get started. Our article on the Logic Energy investor model explains the direct investment model for investors in detail.
Returns, predictability, and tax optimization all in one asset class—that’s what solar power offers in a combination that ETFs, real estate, and money market accounts cannot match on their own. Learn more about PV investing now →
No comparison of returns can replace a calculation based on your specific situation. Logic Energy calculates the individual return potential of a solar power system for each prospective customer—based on actual system costs, the current feed-in tariff model, and your personal tax situation. The result provides the data you need to make an informed decision between asset classes. Contact us—free of charge and with no obligation. Go to the contact page →
Disclaimer: This article is intended solely for general informational purposes and does not constitute investment, tax, or legal advice. Return figures are based on historical data and are not a guarantee of future results. All figures are subject to change. As of March 2026.
FAQ
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PV is a predictable but not risk-free investment. The EEG feed-in tariff provides legally guaranteed minimum revenues for 20 years. Real risks include regulatory changes (EEG reform in 2027), market price fluctuations in direct marketing, and technical failures. Compared to ETFs, PV is less volatile but also less liquid. Compared to money market accounts, it offers significantly higher returns with a correspondingly longer capital commitment.
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Commercial rooftop and ground-mounted systems in Germany typically generate a pre-tax return of 6–10% per year in 2026. Residential rooftop systems yield 3.5–8%, depending on the self-consumption rate. Through tax instruments such as the IAB and special depreciation, the after-tax return for investors with a high marginal tax rate can be significantly higher. (Source: Helm Group, portfolio data 2024)
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PV offers a legally guaranteed minimum rate of return, a lower initial investment, minimal administrative overhead, and no tenant-related risks. Real estate offers tax-free capital gains after 10 years and stronger inflation hedging through index-linked rents, but has significantly higher transaction costs, concentration risk, and regulatory pressure due to renovation obligations. The gross return on commercial PV systems exceeds the net rental yield of urban real estate in most cases.
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PV is an illiquid long-term investment. While an investment can be sold, there is no secondary market as there is for ETFs. Anyone who needs capital in the short term should only include PV as part of a portfolio that contains sufficient liquid reserves. The investment horizon is typically 20–40 years.
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Existing plants are protected by grandfathering provisions: The feed-in tariff set at the time of commissioning applies for 20 years, regardless of subsequent legislative changes. The planned 2027 EEG reform applies only to new plants following the transition to Contracts for Difference (CfD). Plants that go into operation before July 17, 2027, will retain the existing terms. (Source: EU Regulation 2024/1747; BMWE working draft, January 2026)
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A small residential rooftop system (5 kWp) starts at €6,000–€10,000. For a tax-optimized commercial system with IAB usage, a cost of €50,000–€100,000 is realistic. The Logic Energy model allows you to get started as an investor by purchasing a stake in one or more inverters—please contact us directly for specific entry requirements.
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ETFs offer maximum liquidity, broad diversification, and historically high long-term returns—but without capital protection and with significant volatility. PV offers predictable cash flows with a statutory minimum guarantee, the characteristics of a tangible asset, and unique tax advantages; however, it is illiquid and concentrated in a single sector. ETFs and PV can complement each other well in a portfolio—neither is a competitor, but rather a different tool.
References
MyInvest24 – Real Estate as an Investment in Germany in 2025
Section 7g of the Income Tax Act (EStG) – IAB and Special Depreciation Allowances
All information is provided without warranty. As of March 2026.
