Plug-in solar in Düsseldorf: with or without a battery in 2026?
On a south-west balcony, 900 Wp produce 607 kWh a year in Düsseldorf; a 1 kWh battery brings 146 kWh more of it into your own household.
Checked by Radif Partners · Editorial policy · How we calculate
Saving per year
€154
670 kWh of solar power, 63 % of it used at home
| Generation per year | 670 kWh |
|---|---|
| of which used at home | 425 kWh · 63 % |
| into the grid, unpaid | 245 kWh |
| clipped by the inverter (800 VA) | 1 kWh |
| Saving on the electricity bill | €154 |
| Payback | 2.9 years |
| Saving over 20 years | €3,079 |
Step-by-step calculation
- Postcode 40213 (area of Düsseldorf): 1,032 kWh per kWp at 35° south according to PVGIS for the centre of the postcode.
- Tilt 90° and the chosen direction: 746 kWh per kWp. Times 0.90 kWp: 672 kWh before the inverter.
- Quarter-hour by quarter-hour against 74 metered households using 2,500 kWh a year: the household uses 63 % of the output itself.
- 425 kWh × 36.2 ct = €154 a year; €450 purchase price ÷ saving = payback.
Estimate based on average weather 2005 to 2023 (PVGIS) and metered household loads. A single year can differ by a few per cent. How we calculate
Düsseldorf sits just behind Cologne for solar yield: PVGIS gives 1,033 kWh per kilowatt peak at 35 degrees south for postcode 40213, rank 10 of 15 big cities. In the Market Master Data Register the city stands out for its batteries: 7,188 storage units against 8,346 building-mounted solar systems, 0.86 per system and well above the national 0.58. Plug-in devices (Balkonkraftwerke), by contrast, are rare: 3,789 devices or 6.1 per 1,000 residents, rank 14 among the cities. A 900 Wp device hung upright on a south-west balcony produces 607 kWh a year. A couple using 2,400 kWh consume 386 kWh of it themselves and save €140 at 36.2 cents per kWh. A 1 kWh battery would add €53 a year, a 2 kWh one €68. Whether storage pays therefore depends on its price.
What the register reveals about Düsseldorf
| Indicator | Düsseldorf | Germany or rank |
|---|---|---|
| Yield per kWp, 35° south | 1,033 kWh | rank 10 of 15 |
| Plug-in devices in operation | 3,789 | |
| per 1,000 residents | 6.1 | Germany 18.3 |
| Solar systems on buildings | 8,346 | |
| Storage units | 7,188 | |
| Batteries per building system | 0.86 | Germany 0.58, rank 3 |
| Full feed-in systems | 10.3 % |
Two values stand out. In Düsseldorf almost every roof system comes with a battery, while the city has one of the lowest densities of plug-in devices. People with their own roof clearly aim for maximum self-consumption; renters have so far been slower to pick up a plug-in device.
A balcony battery, worked through
A couple in Bilk, both partly working from home, 2,400 kWh a year. Their third-floor balcony faces south-west with no shade. The device costs €450, the battery is optional. The load profiles behind the engine come from the HTW Berlin measurement series.
| Option | Used at home | More than without | Value of the extra/year | Total saving |
|---|---|---|---|---|
| no battery | 386 kWh | €140 | ||
| 1 kWh battery | 532 kWh | 146 kWh | €53 | €193 |
| 2 kWh battery | 575 kWh | 188 kWh | €68 | €208 |
The second kilowatt hour of storage adds less than the first, because on many days even the small battery does not fill up. Without a battery the device pays for itself in 3.2 years. The battery needs its own sum: its price divided by the value of the extra gives the years to break even, and those should be fewer than its expected lifetime. How big a battery should be is explained in the guide to battery size.
Rhineland neighbours: Düsseldorf and Cologne
The two city centres are 34 kilometres apart as the crow flies, both in the Lower Rhine Basin, both flat along the river. Yield barely separates them: 1,033 against 1,038 kWh per kWp, 607 against 610 kWh on a south-west balcony. Uptake does: Cologne has 7.6 plug-in devices per 1,000 residents, Düsseldorf 6.1. The weather cannot be the reason.
Lower Rhine weather: mild but grey in winter
The PVGIS point for the centre lies at 35 metres, open to westerly winds from the Atlantic. Winters are mild but often overcast. November to February contribute 15.7 % of annual yield, rank 6 among the cities. In December the example device produces 17.3 kWh, by March already 54 kWh. On roofs, 33 % of systems face mainly south and 19 % south-west. Tenants are entitled to permission under section 554 Civil Code; the only registration is in the Market Master Data Register.