Solar Panel Savings Calculator

A well-oriented 3 kWp system produces on average between 3,300 and 4,500 kWh per year, depending on the area: about 1,100 kWh per kWp in the North, 1,300 in the Centre and up to 1,500 in the South. These are indicative figures, also affected by orientation, tilt and shading.

Savings depend mainly on self-consumption. With a 3 kWp system and 30-40% self-consumption you typically save €600-900 a year; with a storage battery, which pushes self-consumption above 60-70%, savings can exceed €1,000 a year. What matters is how much energy you use directly: it is worth far more than the income from selling to the grid.

Self-consumption is the share of the energy produced by the panels that you use directly at home instead of feeding into the grid. It matters enormously because every self-consumed kWh saves you the full purchase price (e.g. €0.28/kWh), whereas energy sold to the grid is paid much less (often €0.08-0.12/kWh). The higher your self-consumption, the bigger your savings.

Typical payback times range from 6 to 10 years: you calculate them by dividing the system cost by the yearly saving. With good self-consumption and high energy prices the time shortens; with tax deductions (e.g. building renovation schemes) it is reduced further. Since panels last 25-30 years, once paid off the energy produced is practically free.

A battery is worthwhile if your consumption is concentrated in the evening and at night, when the panels are not producing. It lets you use the energy stored during the day, raising self-consumption from 30% to over 60-70%. However it has a significant cost: weigh the sizing carefully, because an oversized battery can lengthen the payback more than it saves.

What changes is the solar irradiation, hence the yield per installed kWp: roughly about 1,100 kWh/kWp in the North, 1,300 in the Centre and 1,500 in the South. For the same system, the same 3 kWp produces more (and so saves more) the further south you go. This is why payback in the South is generally shorter.

In Italy domestic solar usually falls under building-renovation tax deductions, which let you recover part of the cost over several years through your tax return (the percentage and caps change over time). There is also the net-metering / dedicated withdrawal scheme to value the energy fed in, plus possible incentives for Renewable Energy Communities. Always check the rules in force at the time of installation.

It is the share of what the panels produce that you use at home instead of feeding into the grid. It matters because every kWh used at home saves the full purchase price, while one fed into the grid is paid back at far less.

Yes, and not because we promise it: this tool runs entirely inside your browser. What you type or upload never leaves your device, so it never reaches a server of ours and there is nothing we could keep, read or lose. You can check it yourself: open the page, disconnect from the internet, and the tool keeps working.

No. There is no database behind this tool: we do not store your files, your text or your results. When you close the tab nothing is left — not here with us, because it never arrived, and not anywhere else.

We do not profile you: there is no account to create, we never ask for your email to use a tool, and we keep no profile of what you do. We are an Italian company and we work under the GDPR and the other European rules, with the privacy notice and the consent request in plain sight. One thing we say in full rather than hiding it behind a slogan: the ads on the page are Google's, and Google may use cookies to personalise them. You decide from the consent banner: if you say no the ads stay, but they are not personalised, and the tool works exactly the same.

From the ads on the page, and that is all. We do not sell your data, there is no hidden paid plan, there is no limit that eventually asks for your card, and you do not have to sign up. The ads pay for the servers and for the time we spend writing the tools: that is how we can keep them open to everyone.