The electric car in the garage

On this page

1. How much does an electric car use?
2. Charging power against charging time
3. The main fuse is the limit, not the car
4. What does a mil cost at home?
5. The best load in the house to move in time
6. The green deduction for a charging point
7. The trap: biggest is not best
8. Check yourself

How much does an electric car use?

We start with the only figure that matters: how many kilowatt-hours the car actually buys over a year. Everything else in this module hangs on it.

A Swedish passenger car covers 1 126 mil a year — that is Trafikanalys's measurement of distances driven, from 2022, and it is the average across all passenger cars, not only electric ones. A mil is the Swedish mile, ten kilometres. Our engine assumes an electric car uses roughly 1.56 kWh per mil at the wheels.

1 126 mil × 1.56 kWh/mil = 1 757 kWh

But that is the energy that comes out at the wheels. Charging is not free: some of it is lost as heat in the cable, in the charger and in the battery. Add those losses back and you land at roughly 2 000 kWh a year. That is the figure our engine uses, and the one we work from for the rest of this page.

That also gives a figure more useful than anything else in this module: how much you pay for at the socket, per mil.

2 000 kWh ÷ 1 126 mil = 1.78 kWh per mil

A third more household electricity

Now the figure becomes meaningful. An average Swedish house used 5 654 kWh of household electricity during 2024 — all the lighting, all the appliances, fridge, freezer, laundry and chargers together, according to Energimyndigheten's official statistics. The car puts 2 000 kWh on top of that.

2 000 ÷ 5 654 = 0.35  →  35 % more

So an electric car adds roughly a third to an ordinary house's electricity use. Nothing else you can buy for the house does that in one step. It is why the car deserves a module of its own, and why it shows up so plainly on the bill the month after it arrives.

What the car adds, kWh of electricity a year

• Household electricity in an average house5 654

• The same house, with an electric car7 654

• An electrically heated house, all electricity14 500

• The same heated house, with an electric car16 500

The same car, two different houses. In a house without electric heating 2 000 kWh is a third more (2 000 ÷ 5 654 = 0.35). In a house heated by electricity it is only a seventh (2 000 ÷ 14 500 = 0.14). The household electricity figure is Energimyndigheten's 2024 statistic; the 14 500 is derived by us from the same statistics, for houses with a ground-source heat pump.

Charging power against charging time

This is where the difference between a kilowatt and a kilowatt-hour finally pays off. The charger has a power, in kilowatts. The car needs an amount, in kilowatt-hours. The time is one divided by the other, and nothing else.

hours = kWh ÷ kW

Two charging powers cover almost every house. A single-phase 16 A charging point sits on one of the house's three phases, and one phase carries 230 volts. Voltage times current gives power, exactly as in the module on electricity.

230 V × 16 A = 3 680 W ≈ 3.7 kW

A three-phase 16 A charging point does the same thing on all three phases at once. Three times as much, then.

3 × 3.68 kW = 11.0 kW

And now the thing that settles it. An average car drives 1 126 mil a year, so a little over three mil a day. Counted in electricity that is:

2 000 kWh ÷ 365 = 5.5 kWh a day  →  5.5 ÷ 3.7 = 1.5 hours

Ninety minutes. That is what an ordinary day's driving costs in charging time on the slow charger. The car sits parked for ten, twelve, thirteen hours. The difference between 3.7 kW and 11 kW is real — but it plays out inside a window where nobody is awake to watch it.

How long it takes to put a day's driving back in

The conclusion is awkward for anyone selling chargers, and it is true anyway: for ordinary commuting the slow charger is more than enough. The fast one only wins on the evenings when you get home late from a long journey and have to leave early again. Count how many such evenings you genuinely have in a year before you pay for them.

The main fuse is the limit, not the car

This section ties the module back to what electricity is. The main fuse does not measure energy. It measures current, in amperes, on each of the house's three phases, at this very moment. Cross the limit and it blows — no matter how little electricity you have used over the day.

Grid companies' price lists for houses start at 16 A and continue with 20 A and 25 A. Say the house has 20 A. Then each phase has twenty amperes to share out. The charger takes sixteen of them, on the phase it is wired to.

20 A − 16 A = 4 A  →  4 × 230 V = 920 W left

920 watts. That is what is left on that phase while the car charges. A 2 000 W kettle draws 8.7 A. An oven that consumes 1.8 kWh per hour of use draws 7.8 A. Either of them, on the wrong phase, at the wrong moment:

16 A + 8.7 A = 24.7 A  >  20 A

Half the house goes dark, and there is a fuse to change. It is not the car's fault and not the charger's — it is the sum of two things that happened to be running at the same time.

Load balancing, in plain words

The solution is simple and it is called load balancing. A small current sensor is fitted around the incoming cables at the consumer unit, and it senses continuously how many amperes the house is drawing on each phase. It tells the charger.

When you switch the oven on, the charger backs off. It lowers its current so the total stays under the fuse's limit — from 16 A down to perhaps 8 A, or to zero if the house needs everything. When the oven goes off, the charger comes back up. No fuse blows, and you never have to think about it.

The car loses minutes. You lose nothing — it is standing there until morning anyway.

That is the whole point. Load balancing is what lets an ordinary house charge a car without upgrading its service. Without it you have to size for the worst moment — oven, hob, laundry and car at once — and that lands you in a bigger fuse. With it you size for the day, and the day is long.

A day in the house, and the same charge in two places

What does a mil cost at home?

We now know the car needs 1.78 kWh per mil from the socket. Only one figure is missing: what a kilowatt-hour costs you, everything included. That figure is on your two invoices, and the module on the bill shows how to dig it out.

As a starting point we can use SCB's official price statistics. In the second half of 2025 a household in the villa band — 15 000 kWh a year or more — paid 209.21 öre per kilowatt-hour with retail, grid, energy tax and VAT included. On 1 January 2026 the energy tax fell, which takes just under 10 öre off including VAT. So we work with 2.00 kronor per kilowatt-hour — the same worked example as the rest of the course.

1.78 kWh/mil × 2.00 kr/kWh = 3.56 kr per mil

If the house uses less electricity the price per kilowatt-hour is higher, because the fixed charges are spread over fewer units. In the 5 000–14 999 kWh band the price was 239.84 öre, which makes the mil cost 4.09 kronor instead. And over a year:

2 000 kWh × 2.00 kr = 4 000 kr  ·  at 2.40 kr: 4 800 kr

The comparison with petrol, which we will not make for you

The obvious next question is what the same mil would have cost in a petrol car. We cannot answer it, and we will not guess: we hold no sourced fuel price in the material this course is built on, and last month's fuel price is not a fuel price. The comparison needs today's price at the pump.

But the arithmetic is simple, and you can do it yourself in a minute. Look up today's price per litre, take the car's consumption in litres per mil, and set the result beside your own figure above.

litres/mil × kr/litre = kr per mil   against   1.78 × your kr/kWh

The best load in the house to move in time

Of everything a house does with electricity, the car is the easiest thing to move to another hour. Three things make it unique, and nothing else in the house has all three.

This matters because the price of electricity is no longer one price a day. Since 1 October 2025 the spot price on the Nordic day-ahead market is set for every quarter of an hour, not every hour — that is when the whole European market moved to fifteen-minute resolution. Retailers with more than 200 000 customers must offer a quarter-hourly contract. What that means for the bill is in the module on the bill.

Four times sharper a price signal means it can pay to move a charge by a quarter of an hour, not only by an hour. But how much that is worth nobody can say in advance, and we will not pretend otherwise.

The saving is not the price. It is the difference between the expensive hour and the cheap one, times the kilowatt-hours you move. If the day is flat there is nothing to collect, however clever the charger is.

2 000 kWh × 0.20 kr = 400 kr  ·  × 0.50 kr = 1 000 kr

On top of that comes VAT, which is charged on the whole bill: a spread of 20 öre in the spot price becomes 25 öre on the invoice. And only the variable part moves — the energy tax and the fixed grid charge are the same at three in the morning as at six in the evening.

The grid charge can vary over the day too

Some grid companies offer a time-of-use tariff, where the transfer charge differs between high-load and low-load hours. Vattenfall Eldistribution's tariff from 1 January 2026 is 76.5 öre/kWh at high load and 30.5 öre/kWh at low load, both including VAT. That is 46 öre of difference — more than most spot spreads.

Move the car's whole year to low-load hours and that is 2 000 × 0.46 = 920 kronor. But a time-of-use tariff is optional and not every grid company offers one. Ask yours.

The spread also differs sharply between bidding zones and between years. In 2025 the annual average spot price was 18.50 öre/kWh in SE1 and 66.97 öre/kWh in SE4 — and that is the level, not the spread within a day, that differs so much. So we print no kronor figure here. The gap between your most expensive hour and your cheapest is the only thing that decides it, and you can read that out of your own hourly data.

The green deduction for a charging point

A fixed charging point at the house qualifies for the green deduction, and the rate is 50 per cent. That is the same rate as for a battery, and three times the rate for solar panels, which is 15 per cent from 2026. The deduction comes off the installer's invoice directly — you pay the net amount.

But the rate is not the important part. The ceiling is. The green deduction is capped at 50 000 kronor per person per calendar year, and that ceiling is shared across everything: charging point, battery and solar panels all sit inside the same sum.

In practice a charging point is small in this context, and it is rarely the thing that hits the ceiling. But if you are planning solar the same year the order is worth a thought: whatever comes last in the year is what risks not fitting.

What the deduction is calculated on

For a turnkey installation at a fixed price Skatteverket uses a simplified method: the basis is set at 97 per cent of the invoice. So the deduction is 50 per cent of 0.97 of what you pay, not 50 per cent of the whole sum. Our engine calculates it the same way.

One contested detail: trade press reports that Skatteverket treats inverters as solar material, at 15 per cent rather than 50. We have not been able to verify this, and mention it here because similar boundary questions can arise around a charging installation.

The trap: biggest is not best

Now we can put the whole module together into the one sentence that saves the most money.

And that is where the real cost sits, because a bigger main fuse is a higher fixed charge every month, forever. Two real 2026 price lists, both including VAT:

Set that against what you get. Two thousand kronor a year, every year, to shorten a charge that happens while you sleep anyway — from ninety minutes to thirty. Load balancing costs once. A bigger fuse costs every month. That is the whole trade-off, and for the great majority of houses it points the same way.

Check yourself