Solar Panel Payback Calculator
Instantly calculate the recommended solar plant size, annual output, annual savings and payback period. You don't need to order anything or sign up to see the result, just enter your site's details. If you wish, you can then request a more detailed quote.
Initial estimate
Enter your details to see the estimate.
This is an initial estimate. A precise quote is prepared after an on-site survey.
How the calculator works
We don't hide the basis of the calculation. All model inputs are indicative Estonian 2026 values and shown in the open.
950 kWh / kWp
Annual output per installed kilowatt on a well-oriented roof.
0.18 €/kWh
Retail electricity price including network charges, the rate every self-consumed kWh saves you.
0.055 €/kWh
The price credited for surplus electricity sold to the grid.
40% self-consumption
Assumed share of output consumed on-site; the rest is sold to the grid.
Roof factor
Gable roof 1.0 · hip roof 0.96 · flat roof 0.92 · other 0.90.
System cost
Indicative €/kW falls as the system grows: ~1,120 €/kW for a small system, ~950 €/kW from 30 kW.
These are indicative constants for a first estimate. The real result depends on roof orientation, pitch, shading, condition and your consumption profile.
Why a precise quote requires an on-site survey
- Roof orientation and pitch, a south-facing roof produces the most
- Shading from trees, chimneys and neighbouring buildings
- Self-consumption share, the more of the output you use right away, the better the payback
- Electricity price and how it changes over time
- Battery storage, which raises self-consumption
- Roof condition and load-bearing capacity
Add the calculator to your website
Run a real-estate blog, an apartment association site or a construction portal? Add this calculator to your site for free. Copy the code and paste it into your HTML.
<iframe src="https://profielekter.ee/kalkulaator-embed"
width="100%" height="900" style="border:0"
loading="lazy" title="Solar panel payback calculator"></iframe>The widget works on any site and links back to ProfiElekter. If you have questions, call +372 56465279.
Payback calculator, FAQ
The calculator estimates the system size from your roof area or monthly electricity cost, calculates the annual output (in Estonia roughly 950 kWh per installed kWp on a well-oriented roof), multiplies it by the roof-type factor, and works out the savings based on the shares of self-consumption and grid export. The result is an initial estimate.
The result is indicative and meant for initial orientation. A precise quote always requires an on-site survey, because roof orientation, pitch, shading and condition significantly affect the outcome.
Indicative Estonian 2026 inputs: annual output 950 kWh/kWp, retail price including network charges 0.18 €/kWh, grid feed-in price 0.055 €/kWh, self-consumption share 40%. These are shown in the open and refined when we prepare a quote.
In Estonia, the payback period for a residential solar plant is typically 8–12 years, depending on the electricity price, self-consumption share and roof position.