☀️ Calculate the payback time
For solar panels, a heat pump, insulation or another investment: see after how many years it pays for itself.
💡 How is it calculated?
The formula behind the payback time.
Net investment = Investment − Grant
Yearly return = Savings − Maintenance
The calculator adds up the return year by year until the net investment is paid back. With a price increase, the savings grow a little every year.
This is a simplified estimate without financing costs or replacing parts, such as an inverter.
❓ Frequently asked questions
Answers to the most common questions.
☀️ How do I know how much I save per year?
Ask your installer or energy advisor, or compare your energy bills before and after. For solar panels, it depends heavily on how much of the electricity you use directly yourself.
🎁 Which grants are available?
This differs per region and changes regularly. Check your region's website or ask your municipality or grid operator.
📊 What is a good payback time?
The shorter, the better. As a rule of thumb, an investment is worthwhile if it pays back well within its lifespan, so you profit for years afterwards.
🔗 Other calculators
Check out these handy tools too.