Monthly Solar Yield: How Much Power Your PV System Really Delivers

How much electricity a solar system produces depends strongly on the month and location. Between the peak month of June and the weakest month of December, there is a factor of up to 10. In this reference article, you’ll find monthly PVGIS yield values for North, Central and South Germany, learn to understand seasonal patterns, and discover why May often beats July.

Monthly Yield Values Overview

The following table shows typical yield values in kWh per installed kWp, broken down by three reference locations. Data is based on long-term PVGIS averages from the European Commission.

Typical monthly yields in kWh/kWp | Source: PVGIS (EU Science Hub), long-term averages

Month↕	North (Hamburg)↕	Central (Berlin)↕	South (Munich)↕
January	25	30	40
February	40	45	55
March	75	80	90
April	110	115	120
May	130	135	140
June	135	140	145
July	130	135	140
August	115	120	130
September	85	90	100
October	50	55	65
November	25	30	35
December	15	20	30

Annual Totals Compared

North (Hamburg)935 kWh/kWp

Central (Berlin)995 kWh/kWp

South (Munich)1.090 kWh/kWp

Sum of monthly yield values | Source: PVGIS

The difference between Hamburg and Munich is about 155 kWh/kWp per year — roughly 16%. For a typical 10 kWp system, that means Munich produces about 1,550 kWh more annually than Hamburg.

Understanding Seasonal Yield Patterns

Jan30 kWh/kWp

Feb45 kWh/kWp

Mar80 kWh/kWp

Apr115 kWh/kWp

May135 kWh/kWp

Jun140 kWh/kWp

Jul135 kWh/kWp

Aug120 kWh/kWp

Sep90 kWh/kWp

Oct55 kWh/kWp

Nov30 kWh/kWp

Dec20 kWh/kWp

Average values for Central Germany (Berlin) | Source: PVGIS

The yield follows a distinctive bell curve. Three phases are clearly distinguishable:

Spring Rise (March — May)

From March, yield increases sharply. Day length grows significantly (from about 11 to 16 hours), and the sun angle becomes steeper. At the same time, temperatures remain moderate, which benefits module efficiency. March alone delivers more than January and February combined.

Summer Plateau (May — August)

The four summer months together generate about 40% of the annual yield. Notably: May and July deliver nearly identical values, although July receives significantly more global irradiance. The reason lies in temperature.

Autumn Decline (September — November)

In September, yields fall back to March levels. From October, they drop steeply. By November, values reach winter levels.

Why May Often Beats July

Many system owners are surprised: May regularly achieves equal or even higher yields than July — despite longer days and stronger sunshine in July.

Three factors combine:

1. Temperature coefficient: Modules operate at 35-45°C in May, at 50-65°C in July. Every degree above 25°C costs output.
2. Day length: In May, days are already nearly as long as in June/July (approx. 15.5 vs. 16.5 hours in northern Germany).
3. Humidity: In midsummer, the air is often hazier, reducing direct irradiance.

For more on how different module types handle temperature, see our article on solar cell efficiency.

Regional Differences: Munich vs. Hamburg vs. Berlin

Location comparison | Sources: PVGIS, DWD

Feature	Hamburg	Berlin	Munich
Annual yield (kWh/kWp)	935	995	1,090
Global irradiance (kWh/m²)	1,050	1,120	1,200
Sunshine hours/year	1,560	1,740	1,780
Best month	June (135)	June (140)	June (145)
Weakest month	Dec (15)	Dec (20)	Dec (30)
Yield 10 kWp system (kWh/yr)	9,350	9,950	10,900

Winter Yield: What’s Possible in December and January

Winter is the lowest-yield phase. In December, a system in the North produces only about 15 kWh/kWp, in the South about 30 kWh/kWp. For a typical 10 kWp system:

Location	December (kWh)	January (kWh)	February (kWh)	Winter total
Hamburg	150	250	400	800
Berlin	200	300	450	950
Munich	300	400	550	1,250

Summer Yield: The Potential of Peak Season

From April to September, about 75-80% of the annual yield is generated. These six months are decisive for your system’s economics.

Apr-Sep (Summer)77 %

Oct-Mar (Winter)23 %

Yield distribution summer vs. winter half-year | Location: Berlin

Conclusion: Plan Your System’s Yield Realistically

The monthly yield figures show clearly: a solar system is not a uniform power supplier. The yield distribution over the year requires thoughtful planning:

1. Optimise self-consumption: Run power-intensive appliances (washing machine, dishwasher) during summer daytime
2. Size your battery: A battery storage balances daily and partly seasonal fluctuations
3. Use the feed-in tariff: Summer surplus is compensated
4. Realistic expectations: Grid power remains necessary in winter

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