How Kronwatt works
Six steps, in the same order as in Kronwatt. Each step has a box about what it does not do.
1. You describe the house
Kronwatt asks one thing at a time: where the house is, how much electricity it uses a year, counted in A kilowatt-hour (kWh) measures an amount of energy, such as electricity or heat. A new freezer uses about 250 kWh of electricity a year. Glossary: kWh, and how it is heated. Then it asks about an electric car and solar panels, and which contract the house has, for example an A contract where you pay the exchange price hour by hour, or quarter by quarter. Electricity you use while the price is low costs less. Glossary: hourly price.
You can enter the yearly electricity use or upload the house's The electricity the house buys, hour by hour, as the grid company measures it. You can download them from the grid company's website. If the house has solar panels, solar power used directly in the house is not included. Glossary: hourly readings. With hourly readings Kronwatt does not have to guess when the house uses electricity.
What this step does not do
- Kronwatt works out solar on one roof face, not several.
- If the house already has solar panels, don't upload hourly readings. The grid company measures only the electricity bought, and Kronwatt counts it as the house's whole use.
- A battery the house already has cannot be entered.
- The heating answer decides how Kronwatt spreads the house's electricity over the year. Kronwatt gives no advice on the heating system itself.
2. You see the house as a drawing
Kronwatt draws the house with everything you entered: solar panels, heat pump, electric car and contract. Tap a detail to change it.
Kronwatt tells you if the figures don't add up, for example too little electricity for a heat pump and two electric cars.
What this step does not do
- The warning about figures that don't add up is in English.
3. You get a report on the house's electricity
The report has three chapters: Use, Solar and balance, and Cost. It explains each finding in plain words and shows where you see it in the chart.
Which findings does the report show?
For example:
- how much electricity the house always draws, day and night
- how much more it uses in winter than in summer
- when in the day it uses most
- how much it uses when electricity is dearest
- how much of the solar power the house uses itself
- which month the panels produce most and least
Have you only entered the yearly use? Then Kronwatt estimates when in the day the house uses electricity, and the report says so.
What this step does not do
- The report cannot be saved as a PDF or shared with a link.
4. You compare contracts and batteries
Choose the contract and how the battery is run. Kronwatt compares five battery sizes, from 3 to 15 A kilowatt-hour (kWh) measures an amount of energy, such as electricity or heat. A new freezer uses about 250 kWh of electricity a year. Glossary: kWh, with no battery at all. The A tax deduction when you install solar panels or a battery. It comes straight off the invoice, so you pay less from the start. Glossary: green deduction is included.
Your choice of contract and battery is called a package. You see the bill today and with the package, what the package costs and when it has paid for itself. You can save up to six packages and compare them.
What this step does not do
- New solar panels go into the roadmap, step 5, not here.
- Payback is worked out without interest: a krona in ten years counts as a krona today.
- Capacity charges from the grid company are not included.
- The assumptions behind the figures are shown in the app, in English.
5. You plan in several steps
Put solar panels, a battery and contracts into a roadmap for today and the next five years. Set a budget per year and see what each year brings.
Make two purchases in the same year and the green deduction can hit its cap. Part of the deduction is then lost, and Kronwatt shows it.
What this step does not do
- The roadmap is not saved.
- Only solar panels, batteries and contracts are calculated. The cards for reducing demand, heating and transport are greyed out.
- Kronwatt does not suggest a better order for you.
6. You make an offer
A saved package becomes an offer to the homeowner, with your logo, colours and pictures. When you go through it together, the homeowner can untick parts and see how the figures change.
The offer cannot be saved as a PDF or shared with a link. You go through it on screen.
What this step does not do
- The offer is written as an installer's proposal, not as an impartial advisor's report.
What Kronwatt does not do yet
The app does not yet work out insulation, a new heating system or The house's grade for energy use, from A0 (best) to G. It is shown in the energy declaration. Glossary: energy class, and it does not yet write an A plan to renovate a house in steps: what each step costs and saves, and which energy class the house is expected to reach. The rules on what it must contain apply from 1 October 2026. Glossary: energy renovation plan. We want Kronwatt to do that.
You can work out individual measures such as insulation, windows and heat pumps in Åtgärdskalkylen, the free calculator. It works in its own, simpler way.
Good to know: data in the app is stored in Stockholm. The app is in Swedish and English, but some texts, such as the assumptions and warnings, are in English only.
See Kronwatt work through a house you choose
Write to us, and we will work through a house together. Rohi Perlsteyn, one of the founders, will answer.