At home battery stores, you should now keep an eye on your hat

“How the promised return has been calculated”, I ask. The seller of the 14 kilowatt-hour battery system, which costs almost 11,000 euros, cannot answer. A moment before, he has sent me an offer, which says that I will receive an estimated “income” of 2,000–3,000 euros per year from the batteries.

The income would come from the fact that the capacity of the batteries is used in the so-called reserve market for electricity, which is used to balance the electricity system.

Battery dealers seem to be pouring into the market almost as rapidly as solar panel dealers a couple of years ago.

What many battery retailers have in common is that the customer pays a high price for a battery that he gives up control of. The company, which operates batteries remotely, sells capacity collected from dozens of customers’ batteries to the electricity reserve market.

But that’s where the similarities end. There are big differences in the return promises, the operating logic of the systems and the credibility of the companies.

For starters you don’t go to the reserve market just because of that. Operating on the market requires an agreement with the grid company Fingrid, fulfilling a list of requirements and often also testing.

There are several products on the reserve market with varying requirements.

I ask the battery seller if the battery operator already has a contract with Fingrid? The battery dealer states that “it is coming”. He cannot answer whether I would receive the promised returns until the contract is in place. He says the operator is a Chinese battery manufacturer.

The company that manages the batteries must also have a developed information system with which it can control the use of the batteries. If the system promises to also intelligently control the house’s electricity purchases and solar electricity storage, the requirements will increase.

Sen the seller can tell that this particular battery would be used purely for the needs of the reserve market. It would therefore be of no use for timing the house’s own consumption or storing solar electricity.

However, for the owner of the solar panels, it is precisely the storage of solar electricity that could bring a large part of the benefit of the battery.

So I would buy a battery at an expensive price that I can’t control myself, that is managed by a completely unknown company and whose profit assumption is not necessarily based on anything. I would also like some kind of proof that the system works as promised.

So I don’t think there will be any trades. Of course, I sent the request for offers purely for journalistic purposes. But as said, there are big differences in the reliability of operators.

HS told in October About Elisa’s battery system. The company’s promises are moderate compared to others, and they are based on real experience of operating in the reserve market.

At Elisa, a 15 kilowatt-hour battery with inverters and installed costs about 8,000 euros, while other sellers’ prices for a battery system of the same size are about 10,000–15,000 euros. So there can be almost a hundred percent difference already in the purchase price.

Elisa has been selling the battery capacity of its base stations to the reserve market for a couple of years, and has a proven system for managing home batteries.

For there is even evidence of the realized returns of already installed home batteries. This fall, customers received an average of 39 euros per month in reserve market credit.

Elisa’s system, on the other hand, largely uses batteries for timing the household’s own electricity consumption or for storing possible solar electricity. It is an important part of the benefit produced by the batteries.

With the help of timing, according to Elisa’s data, the price of electricity paid by customers decreased to 2.1 cents per kilowatt-hour during the first month of operation, while the price of electricity on the stock exchange was 5.1 cents on average. With a consumption of one thousand kilowatts, it would mean a saving of 30 euros.

When the sun warms up again, owners of solar panels will benefit even more from Elisa’s battery.

HS:n the battery dealer I talked about is not the only one who promises multiple times the reserve market returns for batteries compared to Elisa. Some of the big promises are explained by the fact that some companies completely reserve the battery for the reserve market.

For example, Powera, which sells a 15-kilowatt-hour battery system for around 15,000 euros, uses batteries only in the reserve market, at least in the initial stages, and not at all for regulating home electricity consumption.

CEO of Powera Toni Tillonen according to the calculation provided, a 10 kilowatt-hour battery would have generated an average of 185 euros per month in the FCR-N and FCR-D products of the Finnish reserve market in August–September.

The company plans to develop the software that controls the battery by next spring, so that the battery is also partly used to regulate the home’s electricity consumption.

Finland the Danish company Emaldo has also entered the market, whose home battery systems are sold by at least three retailers. Emaldo’s 15 kilowatt-hour system costs from 10,000 euros upwards.

On the marketing page, it is stated that the return on the reserve market will be 2,200–3,000 euros per year, i.e. 183–250 euros per month. The calculation is based on the return of the last 24 months, according to the site. It is not stated on the page that the return is calculated according to the Danish reserve market, so not Finland.

Tiedon is told by the owner of the Kärkikampantit company that sells and installs the system Arto Hautamäki.

Emaldo promises that the battery will also be used to control the home’s electrical system and store solar electricity. Hautamäki says that about five kilowatts of the battery power is used in the reserve market.

Account power and the ability to store energy are two different things. Storage capacity is the most essential thing in optimizing household purchases and storing solar electricity. In the reserve market, it may be sufficient for the battery to temporarily supply power to the system if, for example, a large power plant unexpectedly goes offline.

It is not easy to figure out with which logic Emaldo ultimately controls the battery for different purposes.

Typically, the customer receives a certain portion of the reserve market’s revenue, and the operating company keeps, for example, 30 percent of it. The battery operator does not benefit from the adjustment of the home’s electrical system. It would therefore be in the company’s interest to maximize the use of the reserve market.

On Emaldo has many years of experience in the Swedish and Danish markets and a proven remote control system. In Sweden, the installation of batteries has been supported by generous state subsidies, and therefore a lot of them have been installed, especially in connection with solar power systems.

According to Hautamäki, Emaldo also already has an agreement with Fingrid to operate in the reserve market.

Profits start to come to customers when there are 60 installed batteries. According to Hautamäki, it fills up quickly.

“We get hundreds and hundreds of inquiries all the time,” he says.

of the reserve market future returns are a big question mark. On the other hand, the need for fast and slow regulation of the electrical system is constantly increasing as more wind and solar power become available.

Still, it can be expected that the rapid proliferation of batteries will eat into profits because there is so much supply coming to the market. Large battery systems are also coming to Finland, which will also enter this market.

A lot of batteries will also be installed in connection with solar and wind power plants in the future.

In general, you should keep a cool head in the battery market. The store has expensive systems, the management of which the payer usually transfers completely to an external company.