For citizens and businesses
Solar tool
SolarSim is a digital tool that helps citizens and businesses find out whether solar panels are a good investment for their building. Our solution is independent, easy to use and gives a realistic assessment of economics, production and CO₂ savings in just a few minutes, with no sales agenda whatsoever.
How the tool works
Selected address
Ågeruphøj 51, 4000 Roskilde
Enter your address
We automatically find your building and prepare hourly weather data and roof data from Denmark's national elevation model.
Eloverblik
Enter manually
Quick estimate
Annual consumption
Import your consumption
Import your actual hourly consumption directly from Eloverblik, or enter it manually.
Mark roof surfaces
Draw the roof surfaces where you want solar panels. Tilt, orientation and shading are calculated automatically.
Solar system
8.4 kWp
Payback period
8.6 yrs
Annual CO2 savings
637 kg/yr
Get your results
Optimized system, payback time, savings and CO₂ reduction based on your consumption.
Example result
A clear decision basis in minutes
Optimized system, payback time, savings and CO₂ reduction based on your consumption.
- 100% independent
- Hourly data resolution
- Shadow model
Recommended solution
Based on your information, we have calculated the solar solution that gives you the greatest economic value. You can click on all the headings if you want more information.
Solar system
8.4 kWp
Consumption
Your annual electricity consumption
Production
Your annual electricity production
Battery size
See other battery sizes here
Payback period
Return on investment
Annual savings
Annual savings from 2028
Total price
Total investment
Self-sufficiency rate
The percentage of your annual consumption that is covered by solar panels
Annual CO2 savings
CO₂ saved per year
Why municipalities make the tool available free of charge
The municipality makes our tool freely available to citizens, businesses and housing associations. The tool makes it possible to investigate the solar potential of your own roof yourself.
The purpose is to create action. By making it simple and transparent to consider solar panels, the ambition is to influence the behaviour of citizens and businesses, so more choose solar, and thereby contribute to the municipality’s climate goals.
Frequently asked questions
Is SolarSim independent?
Yes. SolarSim is an independent calculation tool that helps citizens, businesses and municipalities assess whether solar panels are a good solution. We don't sell solar panels, don't broker offers, and receive no commission from suppliers.
Our only purpose is to provide a precise and objective calculation so you can make a well-informed decision, without commercial interests influencing the result.
We partner with municipalities to make the tool available free of charge, so more people get access to independent knowledge and can contribute to the green transition on an informed basis.
Are south-, east- or west-facing panels best?
The optimal orientation depends on your consumption pattern. SolarSim therefore calculates how the panels can best cover your electricity consumption throughout the day.
Using the electricity yourself is worth more than selling surplus to the grid, where the earnings are typically lower. In many cases the best solution can therefore be to also place panels facing east and west instead of only south.
What is a good payback period for a solar system?
The payback period shows how long it takes before your solar investment has paid for itself through savings on the electricity bill. After this period, the system generates a financial surplus for the rest of its lifetime.
There is no single answer to what a "good" payback period is, because it depends on the system price, your consumption pattern and how you choose to finance the system.
Many choose a green loan, which often has lower interest rates than ordinary loans. That means your annual electricity savings can in many cases cover or even exceed the loan payments, so you can be ahead from day one without spending savings, which can be used for other things instead.
Another way to assess the investment is the internal rate of return (IRR), which shows your average annual return. It can be compared with, for example, historical stock-market returns, the difference is that solar panels provide a more stable and predictable return through electricity savings, while stocks typically fluctuate more with the possibility of higher returns.
Keep in mind that solar panels are a long-term investment. They are less liquid than stocks, but in return they contribute both financial savings and climate action.
Are solar panels a good investment for you?
Search addresses in your municipality… Try our tool hereWe don't sell solar panels