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How to calculate if a solar roof makes economic sense
A photovoltaic system on your home is pretty neat: You produce a big chunk of the energy you need yourself. But it’s also expensive. Does it make economic sense?
The amount of variables to answer this question is overwhelming. Don’t worry, I’ll break it down for you!
What is your energy usage? ⚡
Track your average daily electricity usage. I did that over a year and saw that my wife any me use about 7 kWh per day without heating in our current home.
I currently have an oil heating system and need about 2500 L of oil per year. That is approximately 22,000 kWh of heat per year for heating and warm water. I will switch to a heat pump with a SCOP of 4 soon. That means I will need about 5500 kWh of electricity per year additionally to the 7kWh/day. In total: 8055 kWh/year.
I pay 0.27€/kWh, hence 2174€/year for electricity.
What do you need for a rooftop photovoltaics system?
The components of a photovoltaics system are:
- Solar modules: Sometimes called solar…
