The following calculation tool will answer this question by simply comparing your current electricity price with the cost for PV electricity. For ease of use, the tool uses predetermined values like the electricity price, PV system price and irradiation. These values can be changed if you have more accurate information about the local conditions. The key result is the PV cost per kWh which then can be compared with the grid electricity price to calculate savings on a per kWh basis.
If you have received an quote from a PV installer simply divide your total cost by the system size in kWp. Typical residential systems cost between 1,300 - 1,500 £/kWp and commercial systems between 1,100 - 1,300 £/kWp.
Irradiation in Southern Europe is between 1,300 - 1,800 and in Northern Europe 800 - 1,200 (kWh/sqm/year).
Feed-in tariff support scheme established a time horizon of 20 years while quality modules will operate well beyond 30 years.
The performance ratio is a technical figure mainly depending on the roof orientation, inclination and type of solar modules. For south facing systems it ranges between 0.80 - 0.85.
Typical debt gearings (loans) for PV investments are between 20-30% of the total cost depending on the risk involved. This usually requires a feed-in tariff as a fall back option in case the PV electricity cannot be self-consumed or supplied as expected. If a feed-in tariff is not available then the debt gearing depends on the overall solvency - credit rating - of the individual or company obtaining the loan.
If the financing is based on a long term fixed feed-in tariff, interest rates could be as low as 2%. Otherwise, the common interest rates for consumer loans or commercial loans apply.
This tool is intended to provide an idea if a PV systems makes sense for the interested user. It cannot replace a detailed analysis based on a technical assessment of the location to make investment decisions. The calculations and the input data were programmed and researched to the best of our experts' knowledge. However, the PV Financing consortium takes no responsibility for the accuracy of the information or any loss or damage suffered as a result of using the tool.