PV Output in 2026: How many kWh per kWp is realistic?
Excerpt
In 2026, a PV system in Germany will generate an average of between 900 and 1,100 kWh per installed kilowatt-peak—this is the most important metric for comparing solar systems of different sizes and locations. Here you can read about how the specific yield is determined by solar radiation, performance ratio, and module degradation; what regional differences exist between Freiburg and Kiel; and how much electricity a 5-, 10-, 30-, or 100-kWp photovoltaic system actually produces.
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Rule of thumb for 2026: A professionally installed PV system in Germany generates approximately 1,000 kWh per kWp per year —ranging from 900 kWh/kWp in the north to 1,150 kWh/kWp in southern Germany. With 1,187 kWh/m² of global radiation and over 1,945 hours of sunshine, 2025 was one of the sunniest years since records began in 1983; many systems performed at the upper end of the range. Modern TOPCon and HJT modules now lose only 0.3–0.4% of their output per year; the performance ratio of high-quality systems is currently 80–87%. Over 25 years, this adds up to a total yield of approximately 23,000 kWh per kWp.
For businesses with their own roof space: The specific yield forms the basis of your profitability analysis. If you are planning to install your own system, you can find more detailed investment and payback calculations under " Your Own PV System for Your Business."
For investors in direct investments: The specific yield forms the basis for the revenue forecast for each inverter or system model. You can find information on returns, tax benefits, and contract structures on the Photovoltaic Investment page.
Table of Contents
What does "specific yield" mean?
The specific yield (kWh/kWp/year) indicates how much solar power a PV system generates per kilowatt-peak of installed rated capacity in a year. It allows for a direct comparison of systems of different sizes and locations and is the key metric for profitability calculations—regardless of modules, system capacity, or manufacturer.
Three terms are often confused in PV practice, but they should be clearly distinguished:
Rated power (kWp — kilowatt-peak): The maximum power output of the PV modules under standardized test conditions (1,000 W/m² of solar irradiance, 25 °C module temperature, AM 1.5). Purely a laboratory figure — not the operating point of a solar system on a German roof. Watt peak (Wp) is the smaller unit; 1 kWp = 1,000 Wp.
Output (kWh): The actual amount of electrical energy generated over a given period (day, month, year). Also referred to as "electricity output" or "power yield."
Specific annual yield (kWh/kWp/year): Annual yield divided by rated power. An 8-kWp system in Munich that generates 9,200 kWh of electricity has the same specific yield (1,150 kWh/kWp) as an 80-kWp system at the same location that generates 92,000 kWh—hence the comparability.
Calculation:
Annual yield (kWh) = Rated power (kWp) × Specific yield (kWh/kWp)
Specific yield (kWh/kWp) = Annual yield (kWh) ÷ Rated power (kWp)
On average across all locations and years in Germany, the specific yield is around 1,000 kWh/kWp —a figure that has been cited as a benchmark for years in the Fraunhofer ISE’s *Current Facts on Photovoltaics in Germany* and is also confirmed by the EU database PVGIS.
Current figures for 2025/2026: Global radiation, hours of sunshine, PV generation
With 1,187 kWh/m² of global radiation, 2025 was the fourth-sunniest year since records began in 1983, and with over 1,945 hours of sunshine, it was one of the five sunniest years on record. Germany’s PV fleet generated around 87 TWh of solar power—21% more than in 2024 and enough to surpass lignite and natural gas in electricity generation.
| Key figure | Value 2025 | Comparison |
|---|---|---|
| Total solar radiation in Germany | 1,187 kWh/m² | Ranked 4th since 1983 · approx. 9% above the 1991–2020 average |
| Sunshine duration | over 1,945 hours | +26% compared to the 1961–1990 climate average · One of the top 5 years since 1951 |
| Solar power generation | 87 TWh | +21% compared to 2024 (72.2 TWh) |
| Share of solar power in the electricity mix | ~16,8 % | for the first time, ahead of lignite (67 TWh) and natural gas (52 TWh) |
| Installed PV capacity by the end of 2025 | ~117 GW | 2025 EEG target (108 GW) slightly exceeded |
| As of January 2026 (BNetzA) | 119.55 GW | 5.7 million systems, including 1.2 million plug-in solar devices |
| Record-breaking June 2025 | 12.0 TWh of PV generation | 10.04 TWh fed into the grid + 1.94 TWh self-consumption |
| Total solar radiation and hours of sunshine: DWD press release "Weather in Germany in 2025," December 30, 2025. PV generation and installed capacity: Fraunhofer ISE Energy Charts, annual report January 2, 2026; Federal Network Agency Market Master Data Register, as of January 2026. | ||
Important note: 2025 was an exceptional year for solar power generation in Germany. For a reliable cost-benefit analysis covering a 20- or 30-year system lifespan, you should not base your calculations on the peak values from 2025, but rather on the long-term average—that is, approximately 1,000 kWh/kWp at an average location.
A quick note on terminology: hours of sunshine ≠ full-load hours. The 1,945 hours of sunshine in 2025 refer to the time during which the sun was visible without being filtered. The full-load hours of a solar system—that is, the time during which it theoretically generates power at its rated capacity—amount to around 1,000 hours per year, because diffuse light also generates electricity, but the module output rarely reaches 100%.
How many kWh per kWp in your region?
The north-south gradient in PV yield in Germany is approximately 15–20%. In Freiburg, on Lake Constance, or in the Saarland, systems generate 1,100–1,160 kWh/kWp; in Hamburg, Kiel, or on the Baltic Sea, 900–970 kWh/kWp. For a 10-kWp system, that amounts to a difference of about 2,000 kWh per year—40,000 kWh over 20 years.
Total solar radiation—that is, the total amount of solar energy per square meter—is not distributed evenly across Germany. In terms of climate, southern Germany receives 1,150–1,300 kWh/m² of annual solar radiation, while northern Germany receives 950–1,080 kWh/m². In 2025, peak values even reached up to 1,350 kWh/m² in Saarland, the Rhine-Neckar region, Breisgau, Lake Constance, and the Bavarian Forest.
| City / Region | State | Total solar radiation (kWh/m²) | kWh/kWp·year |
|---|---|---|---|
| Freiburg | Baden-Württemberg | 1,250–1,300 | 1,100–1,160 |
| Munich | Bavaria | 1,180–1,230 | 1,080–1,130 |
| Stuttgart | Baden-Württemberg | 1,150–1,200 | 1,050–1,100 |
| Nuremberg | Bavaria | 1,130–1,180 | 1,030–1,080 |
| Frankfurt | Hesse | 1,100–1,150 | 1,020–1,070 |
| Berlin / Potsdam | Berlin / Brandenburg | 1,060–1,110 | 1,000–1,055 |
| Cologne | North Rhine-Westphalia | 1,030–1,080 | 970–1,020 |
| Hanover | Lower Saxony | 1,000–1,050 | 950–990 |
| Hamburg | Hamburg | 970–1,020 | 920–970 |
| Kiel | Schleswig-Holstein | 950–1,000 | 900–950 |
| Calculation performed using PVGIS version 5.2, PVGIS-SARAH2 database (15-year average). Standardized assumptions: monocrystalline modules, 14% system losses (inverter, cabling, soiling, mismatch, temperature). Actual yields vary by ±10–15% from year to year. | |||
The difference in solar yield may seem small— but for a 10-kWp photovoltaic system, there is a difference of about 2,000 kWh per year between Freiburg and Hamburg. Over a 20-year lifespan, that adds up to 40,000 kWh—at an industrial electricity rate of 25 cents per kWh, that amounts to a difference of €10,000 due solely to the location.
PV Output Over the Course of the Year: The Monthly Trend
A German photovoltaic system generates about 70% of its annual output between April and September; the summer months of May through August alone account for roughly half of that. In December, the same system generates only 2–3% of its annual output—the ratio of June to December is about 7:1, depending on the season and weather.
Seasonal distribution is critical to economic viability: If a company’s electricity demand remains steady throughout the year, but a system produces a surplus in the summer and does not supply enough in the winter, this affects the self-consumption rate and storage capacity.
| Month | Share of annual revenue | kWh/kWp (at 1,000 kWh/kWp·a) |
|---|---|---|
| January | 2–3% | 20–30 |
| February | 4–5% | 40–50 |
| March | 8–9% | 80–95 |
| April | 11–12% | 110–125 |
| May | 13–15% | 130–150 |
| June | 13–15% | 130–155 |
| July | 13–14% | 125–145 |
| August | 12–13% | 115–135 |
| September | 9–10% | 90–105 |
| October | 6–7% | 55–70 |
| November | 3–4% | 25–35 |
| December | 2–3% | 17–30 |
| Summer months (April–September): approximately 70% of annual output. Four months (May–August): approximately 50–55%. Ratio of June to December: 7:1 to 9:1. With a two-axis tracker or an optimized east-west mounting system, the curve may be flatter. | ||
This distribution is relevant for two investment decisions: First, for storage sizing—those who want to be off-grid in the winter need disproportionately large storage systems because daily PV generation is low during that time. Second, for the self-consumption rate—companies with consumption that is concentrated in the summer (air conditioning, cold storage, irrigation) benefit disproportionately. Those who want to delve deeper into self-consumption and storage economics can find the mechanics in detail under PV with Battery Storage: Co-location, Self-Consumption, and Economics 2026.
How much electricity does a 10 kWp PV system generate? — Sample calculations for systems ranging from 5 to 100 kWp
A 5-kWp system in Germany produces an annual yield of around 5,000 kWh—which corresponds to an average daily yield of about 14 kWh, 25 kWh on a sunny summer day, and 3 kWh on a cloudy winter day. These values scale linearly with system size: 10 kWp = 10,000 kWh, 30 kWp = 30,000 kWh, 100 kWp = 100,000 kWh — with a ±10–15% margin of error depending on the location.
| Appendix | Annual yield (average) | North–South Bandwidth | Average daily temperature in summer (May–August) | Average daily temperature in winter (Nov–Feb) |
|---|---|---|---|---|
| 5 kWp typical single-family home | 5,000 kWh | 4,500–5,750 kWh | 18–25 kWh | 3–6 kWh |
| 10 kWp single-family home / small business | 10,000 kWh | 9,000–11,500 kWh | 35–50 kWh | 5–10 kWh |
| 30 kWp small commercial | 30,000 kWh | 27,000–34,500 kWh | 105–150 kWh | 15–30 kWh |
| 100 kWp commercial/industrial roof | 100,000 kWh | 90,000–115,000 kWh | 350–500 kWh | 50–100 kWh |
| The range is due to regional differences in global radiation (see Section 3). Daily values are monthly averages—a single sunny day in June can yield as much as 60 kWh from a 10-kWp system, while an overcast day in December yields only 1–2 kWh. Calculated by Logic Energy based on data from Fraunhofer ISE / PVGIS. | ||||
Calculation example based on a 10 kWp PV system:
Annual output = 10 kWp × 1,000 kWh/kWp = 10,000 kWh
Summer months (April–September, ~70%): 7,000 kWh ÷ 183 days = ~38 kWh/day
Winter months (October–March, ~30%): 3,000 kWh ÷ 182 days = ~16 kWh/day
Peak output on a sunny summer day: up to 60 kWh, with short-term inverter output of 8–9 kW
Cloudy winter day: 2–5 kWh
This linearity in electricity production is also relevant for direct investments: Anyone investing in a 1-MW ground-mounted system (1,000 kWp) can expect an annual yield of approximately 1,000,000 kWh —scaling up to the double-digit megawatt range works precisely because the specific yield does not depend on the size of the system.
What Affects Solar Power Output? — Nine Factors
The specific yield is determined by nine factors: location and solar radiation (±20%), building orientation and tilt (up to −30%), shading (up to −20%), soiling (2–5% annually), module temperature (in summer −10%), module efficiency, inverter efficiency, cabling losses, and the difference between the data sheet specifications and the actual performance of the PV modules.
| factor | Typical effect | Note |
|---|---|---|
| Location (global radiation) | ±15–20% | South vs. North — see Section 3 |
| Alignment & Tilt | −5% to −30% | South 30° = 100% · East-West 10° = 92% · North 30° = 70% |
| Shading (in certain areas) | −5% to −20% | String WR: The weakest module determines the string — Optimizers and micro-WR mitigate the loss |
| Soiling | −2% to −5% per year | Self-cleaning by rain at slopes of 15° or more — in agricultural environments down to −12% |
| Temperature (60 °C in summer) | −10% to −12% | Temperature coefficient at Pmax: PERC −0.35%/°C · TOPCon −0.30%/°C · HJT −0.25%/°C |
| Module Efficiency 2025/26 | 19–26% | PERC 19–21% · TOPCon 22–23.5% · HJT 24–26% |
| Inverter Efficiency | 96–98.4% | Premium SiC devices achieve >98% Euro efficiency |
| Cabling & Mismatch | −2% to −4% | DC-Kabel 1–2 % · AC-Kabel <1 % · Mismatch 1–2 % · MPP-Tracking 1 % |
| Module Derating vs. Datasheet | −1.2% on average | Fraunhofer ISE CalLab 2024: 1,034 modules measured — neutral before 2017, now systematically underreported |
| By default, PVGIS assumes a 14% system loss as a lump-sum item. Detailed values regarding the tracking and tilt mechanisms can be found in the related technical article on rooftop systems. | ||
In practice, three factors are most often underestimated:
Module underperformance compared to datasheet specifications. A little-known finding from measurements conducted by Fraunhofer ISE CalLab: In 2024, the actual power output of 1,034 measured monocrystalline modules was, on average, 1.2% below the manufacturer’s specifications. Prior to 2017, the deviation was neutral—meaning the discrepancy has only emerged in recent years. For system planning, this means factoring in a 1–2% safety margin.
Soiling. The Federal Network Agency estimates that soiling (dust, pollen, bird droppings, Saharan dust) causes an annual loss of 2–5% in Germany. In agricultural areas with ammonia pollution, the loss can reach up to 12%. Modules with an inclination of less than 15° become dirtier more quickly because rain is less effective at cleaning them.
Module temperature. Modules are calibrated at 25 °C, but their surface temperature can reach 50–70 °C in the summer. At 65 °C, a PERC module loses about 14% of its power output compared to STC, while a modern HJT module loses only about 10%. In midsummer, HJT technology therefore delivers 2–4% higher yield at the same rated power—a factor relevant for ground-mounted systems in southern Germany.
Performance Ratio: Your Investment's Key Performance Indicator
The performance ratio (PR) measures how much of the theoretically possible energy a system actually delivers. Modern systems achieve 80–87%—before the year 2000, the figure was typically around 70%. Values below 75% are a warning sign: in such cases, it is worth having the system inspected.
The PR highlights the difference between weather conditions and system quality. Two systems at the same location should produce similar yields in the same year—if they do not, the specific yield alone does not explain the cause. The PR isolates the system effect by dividing the actual yield by the theoretically possible yield based on measured irradiance.
Calculation: PR = Actual yield (kWh) ÷ [Rated power (kWp) × Global radiation at the module level (kWh/m²) ÷ 1 kW/m²]
Example: A 10-kWp system receives 1,100 kWh/m² of global radiation at the module level and produces an annual yield of 9,000 kWh. PR = 9,000 ÷ (10 × 1 , 100) = 0.818 = 81.8% — a typically good value.
| Public Relations | Rating | Typical system configuration |
|---|---|---|
| over 85% | Excellent | Professional ground-mounted system, new modules, ideal location |
| 80–85% | Excellent · Industry standard | Well-designed rooftop system, modern inverter |
| 75–80% | Acceptable | Suboptimal orientation or slight shading |
| less than 75% | Room for improvement | Shading, dirt, broken strings — Have the system inspected |
| Before 2000, the typical performance ratio of German PV systems was around 70%. The improvement of 10–15 percentage points is due to higher module efficiencies, better MPP trackers, more efficient inverters (96% → 98%+), and glass-glass modules with lower mismatch. | ||
For investors, the PR is relevant for two reasons: First, it determines the revenue forecast (an improvement in PR from 78% to 84% corresponds to approximately an 8% increase in revenue); second, it serves as an objective quality criterion when comparing projects—a facility with a documented PR of over 84% after three years of operation demonstrates sound design and effective monitoring.
Degradation: What will the annual photovoltaic output be after 25 years?
Modern PV modules lose 0.3–0.5% of their power output per year — current-generation TOPCon modules lose 0.4%, while HJT modules lose only 0.25–0.30%. Over 25 years, this adds up to a residual output of 84–88% of the initial output. Manufacturers now offer linear performance warranties covering 25 to 30 years.
Degradation is the most gradual but mathematically decisive factor in life-cycle costs. Unlike weather-related year-to-year fluctuations (±10–15%), it is a monotonous, one-way, and irreversible process.
| Technology | Mainstream 2026 | Premium | Discontinued |
|---|---|---|---|
| Name | TOPCon (n-type) | HJT (Heterojunction) | PERC (p-type) |
| Module efficiency | 22–23.5% | 24–26% | 19–21% |
| Temperature coefficient Pmax | −0.29 to −0.32 %/°C | −0.24 to −0.26 %/°C | −0.34 to −0.35%/°C |
| Annual demotion | 0.3–0.4% | 0.25–0.30% | ~0,5 % |
| Global Market Share in 2024 | more than 65% | ~10 % | ~20 % |
| Typical performance guarantee | 25 years linear, 84.5–85.5% | 30 years linear, 87.4% | 25 years linear, 80–84% |
| In 2024, TOPCon replaced PERC as the market leader in the global module market for the first time (ITRPV Roadmap 2025). HJT modules remain the premium segment, offering the lowest temperature coefficient and the least degradation—though at a higher upfront cost. | |||
25-year calculation with 0.5% linear degradation and an initial value of 1,000 kWh/kWp·a (industry standard):
| Year | Specific yield (kWh/kWp) | cumulative generation |
|---|---|---|
| 1 | 1.000 | 1.000 |
| 5 | 980 | 4.950 |
| 10 | 955 | 9.775 |
| 15 | 930 | 14.475 |
| 20 | 905 | 19.050 |
| 25 | 880 | 23.225 |
| 30 (HJT/Premium) | 855 | 27.260 |
| For TOPCon modules with 0.4% degradation, cumulative 25-year energy production is approximately 1.5% higher (~23,600 kWh/kWp); for HJT modules with 0.30% degradation, it is approximately 3% higher (~23,900 kWh/kWp). Manufacturer performance warranties for modern modules today guarantee 84–88% of the original output after 25 years. | ||
For direct investments with a 20- to 40-year lifespan, degradation is the main reason why revenue forecasts decline over time—a system generates about 12% less electricity in year 25 than in year 1; however, with electricity prices remaining stable or rising, this usually offsets the effect. For companies with their own rooftop systems, degradation means that the self-consumption rate tends to rise over the years as electricity demand grows—which is a desirable side effect from a business perspective.
Theoretical vs. realistic: Putting vendor promises into perspective
Suppliers often advertise 1,100 or even 1,300 kWh/kWp per year—but in reality, an average site typically yields 950–1,050 kWh/kWp during the first few years of operation. The 2–5% difference between the yield forecast and actual electricity yield is due to reduced module performance, optimistic loss estimates, and underestimated shading.
Four common sources of forecast-actual differences:
Optimistic loss estimates. System losses of 8–10% are often assumed in bid calculations—PVGIS uses a more realistic estimate of 14%. Difference: 4–6%.
Specification sheet optimism. The 2024 Fraunhofer CalLab study showed a 1.2% difference between actual performance and the manufacturer's specifications.
Shading is often underestimated during on-site visits. Chimneys, antennas, and neighboring trees look different at midday in the summer than they do when the sun is low in the winter sky. For every shadowed area that is overlooked, there is a 2–5% loss in yield.
Weather variability. According to PV yield databases, the average PV yield in Germany was approximately 1,037 kWh/kWp in 2022, but only 881 kWh/kWp in 2024—a 15% fluctuation. 2025 was another peak year.
Recommendation: Use conservative values for reliable economic feasibility analyses—950 kWh/kWp for central Germany, 1,050 for southern Germany, and 900 for northern Germany. If a provider uses significantly higher values in their calculations, ask about the underlying loss assumptions and the data source (which should be PVGIS-SARAH2 or Meteonorm).
For investors in direct investments, the following also applies: A revenue forecast that does not distinguish between the initial years of operation (with higher returns) and later years (with declining output) is methodologically flawed. Those who wish to delve deeper into research on inverter or system models can find the return structure and investment framework under "Photovoltaic Investment."
Outlook: What does 2026 hold for new investments?
A system newly installed in Germany in 2026 typically generates 1,000–1,080 kWh/kWp in its first year of operation—made possible by higher module efficiencies in mainstream TOPCon modules (22–24%) and performance ratios exceeding 85%. Over a 25-year lifespan, the average is 920–960 kWh/kWp per year.
Three trends are emerging for 2026:
Module efficiencies continue to rise. Mainstream TOPCon modules are expected to achieve 22–24% module efficiency by 2026; HJT is gaining market share in the premium segment. The first perovskite-silicon tandem modules (Oxford PV) are on the market with a module efficiency of 24.5% — widespread adoption not expected until 2027/28.
New installations are shifting toward large-scale systems. In the residential segment, new installations will have declined by 28% by 2025, while ground-mounted and large-scale rooftop systems are growing. Detailed data on this can be found in the cluster article on photovoltaic installations in 2026.
Statistical correction in 2026 following a peak year in 2025. After a year as sunny as 2025, a return to the long-term average is statistically likely. Anyone calculating an initial investment in 2026 based on 2025 figures risks systematic overestimation—it is better to err on the side of caution and use 1,000 kWh/kWp as a baseline.
Important to know
The specific yield is the key metric in any PV profitability analysis—whether you’re planning your own system or making a direct investment. If you want to delve deeper into the investment logic, the overview page provides details on the contract structure, expected returns, and tax benefits.
The question “How many kWh per kWp is realistic?” determines whether a PV system will be a reliable source of returns or a disappointment. At Logic Energy, we design every system using conservative yield assumptions, calibrated modules, and documented performance ratios—and guarantee through the inverter yield-sharing mechanism that investor returns are directly tied to measured generation, not to promises in the prospectus. The contracting party is mediplan Helm e.K., with personal liability of the owner pursuant to Sections 1, 17, and 19 of the German Commercial Code (HGB). If you want to know what specific yield is realistic for your location or a specific project: Contact us for a no-obligation consultation —we’ll openly calculate your location-specific figures.
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. The contracting party for PV direct investments is mediplan Helm e.K. (a registered business with personal liability of the owner pursuant to Sections 1, 17, and 19 of the German Commercial Code (HGB)). As of May 2026.
FAQ
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A 10-kWp system in Germany generates an average of about 10,000 kWh per year over the long term. In southern Germany (Freiburg, Munich), the figure is 11,000–11,500 kWh, while in the north (Hamburg, Kiel) it is closer to 9,000–9,500 kWh. For a south-facing orientation with a 30° tilt and no shading, the specific yield is around 1,000 kWh/kWp.
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A specific yield of 950–1,050 kWh/kWp/year is considered a good figure for central Germany. In southern Germany, 1,050–1,150 kWh/kWp should be achievable, while in the north, 900–970 kWh/kWp is typical. Values below 850 kWh/kWp are a warning sign of alignment, shading, or system issues.
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A 5-kWp system produces an annual average of about 14 kWh per day. On sunny summer days (May through August), it can generate 18–25 kWh, while on overcast winter days (November through February), it generates only 3–6 kWh. The highest daily output is typically reached in June—up to 30 kWh.
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The performance ratio (PR) measures how much of the theoretically possible energy a system actually delivers—it isolates the system’s performance from weather-related factors. Modern systems achieve 80–87%; prior to 2000, the typical value was around 70%. Values below 75% indicate a need for optimization.
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Current TOPCon modules lose about 0.3–0.4% of their output per year, while HJT premium modules lose only 0.25–0.30%. After 25 years, they retain 84–88% of their initial output. Manufacturers now offer linear performance warranties spanning 25 to 30 years—with some glass-glass modules maintaining 87.4% of their original output after 30 years.
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About 30% of the annual yield is produced between October and March—the remaining 70% during the summer months of April through September. December accounts for only 2–3% of the annual yield, while June accounts for 13–15%. The ratio of June to December is about 7:1.
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No. With 1,187 kWh/m² of global radiation, 2025 was the fourth-highest year for radiation since records began in 1983, and with over 1,945 hours of sunshine, it was one of the five sunniest years since 1951. For profitability calculations, you should not use the peak values from 2025, but rather the long-term average of around 1,000 kWh/kWp.
References
Fraunhofer ISE — Current Facts on Photovoltaics in Germany (January 15, 2026) — Specific yield in central Germany: 1,000 kWh/kWp, performance ratio trends, system metrics
Fraunhofer ISE — Photovoltaics Report (October 31, 2025) — Module Efficiency, Degradation Rates, Market Shares: TOPCon/HJT/PERC
Fraunhofer ISE / Energy-Charts — Electricity Generation in Germany in 2025 (January 2, 2026) — PV Generation 87 TWh, Share of the Electricity Mix, Record Month in June 2025
Fraunhofer ISE — Actual solar module performance often overstated (Press Release, March 12, 2025) — CalLab measurement of 1,034 modules, performance shortfall of −1.2%
German Weather Service — Weather in Germany in 2025 (December 30, 2025) — Sunshine duration: 1,945 hours, global radiation: 1,187 kWh/m², among the top 5 years since 1951
DWD — Solar Energy and Radiation Maps — Regional Total Solar Radiation Distribution in Germany
PVGIS — Photovoltaic Geographical Information System (EU JRC) — PVGIS-SARAH2 database for regional yields and monthly distribution
Federal Network Agency — Market Master Data Register — Installed PV Capacity 119.55 GW (January 2026), Monthly Additions
BSW Solar — German Solar Industry Association — Industry Statistics: PV, New Installations in the Residential, Commercial, and Ground-Mounted Segments
HTW Berlin — Solar Storage Systems Research Group — Inverter Efficiency, Energy Storage Inspection
VDI — When Solar Panels Lose Their Light — Soiling Losses of 3–4% Globally, Background on Soiling
ITRPV — International Technology Roadmap for Photovoltaics — Cell technology market shares, n-type wafer share 70%
ADAC — Photovoltaics: Optimizing Tilt Angle and Orientation — Yield Factors by Orientation and Tilt