Any company can embed this calculator on its own website, free of charge, as a simplified version for their clients. Generate a ready-to-use, branded embed code right on this page (section 2 below). For companies that prepare quotes and sell installations professionally, we recommend using the full EasySolar platform instead, available at web.easysolar-app.com.

Table of Contents

1. Try the home energy balance calculator
2. Add this calculator to your website
3. How the calculation works
4. What to pay attention to
5. Example calculation
6. Simplified vs. full version

1. Try the home energy balance calculator Open in a new window ↗

2. Add this calculator to your website

Installers and distributors are welcome to embed the calculator on their own pages, free of charge. Pick your market's language and enter your company name below, the embed code is generated automatically, ready to copy into your site.

Condition of use: embedding this calculator on your own website is permitted only if the built-in EasySolar attribution section (the footer inside the calculator, reading "Kalkulator bilansu tworzony przez EasySolar AI…" together with the EasySolar AI logo and link) stays visible and unmodified. Do not hide it with CSS, crop it out of the iframe, or edit its text or link. Removing or altering this section revokes permission to use the calculator on your site.

Generate your embed code

3. How the calculation works

The calculator models one representative day of the selected month and then scales the result to the full month. Six steps are performed every time you change an input:

1. Energy demand. Your monthly consumption is derived from the bill: demand = monthly bill ÷ electricity price. Dividing by the number of days in the month gives the daily demand.
2. Day / night split. The daily demand is divided according to the consumption profile you pick: Mostly day (70% by day), Steady (50%) or Mostly night (30% by day).
3. PV production. Monthly production comes from an average solar irradiation profile for the selected market and scales linearly with the system power you enter (the reference profile is defined for an 8.4 kWp installation).
4. Daytime allocation. The day's production is split between: direct self-consumption in the home, charging the battery (never more than its capacity, any overflow goes back to the home), charging the electric car, and the remainder is exported to the grid. If production does not cover the daytime demand, the missing energy is imported from the grid instead.
5. Night balance. After sunset the battery discharges first to cover the night demand; whatever it cannot cover is imported from the grid. The state of charge shown on the battery tile reflects this in real time.
6. Monthly bills. Bill without PV is simply your input. bill with PV = grid import × electricity price − grid export × feed-in rate (never below zero). Savings is the difference between the two.

4. What to pay attention to

• Irradiation data is a market average. The English version uses an average profile for California; other language versions use their own market (Poland, Germany, Czechia, Spain, Italy, France, Croatia, Hungary, Portugal, Brazil, Sweden). Your actual roof, its azimuth, tilt and shading, will differ.
• The bill is assumed flat across the year. Real households consume more in some months; the simplification keeps the model readable.
• Fixed allocation shares. By default 20% of production is consumed directly, 40% goes to the battery and 20% to the EV. In a real home these shares move with your habits; the full EasySolar model uses hourly profiles instead.
• The battery is idealised. No round-trip losses, full depth of discharge, and one full cycle per day. Real storage keeps a reserve and loses a few percent on every cycle.
• No tariff schemes. Net-metering, net-billing, time-of-use tariffs and demand charges are not modelled: a single purchase price and a single feed-in rate are used.
• Watch the energy flows. The animated lines show the direction of each flow (PV → home, PV → battery, battery → home, grid exchange). If summer months show large exports while winter shows imports, that is the expected seasonal shape of a northern-hemisphere market.

5. Example calculation (June, California defaults)

Inputs: monthly bill $432, electricity price $1.20/kWh, system power 8.4 kWp, battery 10 kWh, profile Steady.

1. Demand: 432 ÷ 1.20 = 360 kWh/month → 12 kWh/day → 6 kWh by day + 6 kWh by night.
2. Production in June (California average): 1150 kWh/month → 38.3 kWh/day.
3. Battery: 40% of production is 15.3 kWh, more than the 10 kWh capacity, so the battery charges to 100% and the 5.3 kWh overflow is returned to the home.
4. Home: self-consumption plus that overflow easily cover the 6 kWh daytime demand, so there is no daytime import.
5. Electric car: 20% of production = 7.7 kWh ≈ 46 km of range per day.
6. Export: 38.3 − 6 − 7.7 − 10 = 14.7 kWh/day to the grid.
7. Night: the battery covers the whole 6 kWh night demand and ends the night at 40%.
8. Bills: import cost $0, export revenue caps the bill at $0 → savings $432/month.

Switch the month to December to see the winter picture: production drops to a fraction of the summer value, the battery barely charges, and most of the demand is imported.

6. Simplified vs. full version

This home energy balance calculator is a static, simplified model: it uses average irradiation for a whole market, a flat monthly bill and fixed allocation shares. It is built to give you an intuition for the energy balance, not a final quote.

The full version is EasySolar, available after registration at web.easysolar-app.com. It designs the actual installation:

• PV layout on satellite and drone imagery of the real roof, with shading analysis,
• irradiation data for the exact address, not a country average,
• real equipment: panels, inverters and storage from manufacturer databases,
• financial analysis with local tariffs and financing,
• and a complete interactive offer you can send to your client in minutes, viewable in the browser, tracked, and ready to sign.

Create a free EasySolar account and turn this estimate into a real offer →