When you drive electric, you know that you need a large dose of electricity per day to charge the battery. Nowadays we can use solar energy, electricity at off-peak rates and dynamic electricity prices for this. However, this does not always work ideally, because the supply of cheap or green electricity is often at odds with the demand for electricity. The home battery is the ideal solution for this, because it allows you to match supply and demand. However, a home battery is often very expensive, especially if you already have a mobile home battery in the driveway.
Why is the electric car the perfect home battery?
The battery pack of the modern electric car is particularly large and can store more than enough power for your household for several days. In addition, you already have an electric car, so there are no extra costs for a home battery and that saves you a lot of money. In addition, the electric car is perfectly capable of working as a home battery, especially when you have a high maximum charging capacity and can fully charge the battery at the right time. Of course, you do need a strong charging station for this, at least 11 kW (or 22 kW if you already have a heavy-duty connection at home).
Why do you actually need a strong home battery?
There is a particularly large gap between peak demand for electricity and the largest, cheapest supply. Even if you don’t have solar panels, you need the most electricity at the time when the price is highest. If you have an energy contract with off-peak rates and you work outside the home, you have probably noticed that the lowest rates fall precisely at the times when you are not using electricity.
For owners of solar panels, it is not much different. During the day, the panels on the roof yield the most, while you are usually at work or in the garden. When the sun decreases in strength and the panels yield less, the washing machine is turned on, food is cooked, coffee is made and showered. This means that during the peak yield of the solar panels, hardly any power is used and the demand for power suddenly increases sharply when the panels yield much less.
This gap can be closed by the home battery. A home battery is not much more than a huge storage in which the cheap or generated power can be stored until the moment comes when a lot of power is needed. With this you not only ensure that you make optimal use of the possibilities (regardless of whether this is the lowest price per kWh or the power that you have generated yourself), you also contribute directly to a better balance for the power network.
For some people, this all does not sound so serious and topical, which is understandable. However, with the increase in demand for electricity and the lack of possibilities to store large amounts of electricity, this will play an increasingly important role and the electric car as a home battery is an important piece of the puzzle to eventually get everything to fit. Especially because storing green electricity with hydrogen is still not profitable at the time of writing and many people saw this as the solution to tackle the problem.
Can you make do with an electric car?
No, to use the car as a home battery, an electric car that is suitable for bidirectional charging is not enough. You also need a modified charging station and a smart meter in the meter cupboard. Only when you have a suitable electric car, a charging station that supports bidirectional charging and a meter that the charging station can communicate with, it is possible to use the EV as a home battery.
It is often said that you also need solar panels for this. Technically speaking, this is not correct, because with flexible energy contracts (with large differences between the lowest and highest prices) you also benefit from this construction. However, it is true that solar panels can be an important factor, because they can provide free electricity (after the payback period), which can then be stored in your electric car that serves as a home battery. Do take this into account when choosing your charging station: you need a charging station that can be connected to solar panels. Fortunately, the chance that this is the case is extremely high if you were already looking at models that are suitable for bidirectional charging.
A few things you should definitely keep an eye on
The developments around bidirectional charging are not standing still, but at the moment there are few car models that support this and it is still a while before the big breakthrough comes. You can of course already respond to this by opting for a smart charging station, or by having a data cable dug in when you have your (simpler) charging station installed.
At the same time, there are websites that indicate that you should especially look at the battery pack of your next electric car, but we would like to suppress that here. An average household consumes less than 8 kWh per day, which means that the average battery pack ensures that your electric car can already be a home battery that can supply your home with electricity for a week (without being recharged).
Another point that is good to keep in mind is that this construction is not only attractive for large consumers. Even a household with an average consumption benefits from the electric car as a home battery, only the payback period of the construction itself is somewhat longer. With the current trend in energy prices, however, it is the case that even this time will soon be significantly reduced. The fact that you can also use the home battery for your daily transport is of course also a great advantage, because you can already (largely) cross off the costs of your 'battery'.
