Dutch company Borg Energy Storage is preparing to launch its home battery. It will be delivered to the first customers from next year.
It is a revolutionary battery which was designed by the Dutch company Borg Energy Storage. This is not a traditional battery. It is a thermal battery. A thermal battery is an energy storage device that uses heat to store and release energy. Unlike traditional batteries that store chemical energy, a thermal battery stores energy in the form of heat, often by heating a material like molten salt. When it is necessary to release energy, the stored heat is converted into electricity, usually via a thermodynamic engine.
So the Borg Energy Storage battery is actually a thermal tank with a volume of four cubic meters, which you bury underground. The battery has a storage capacity of approximately 200 kilowatt hours. The average house uses around 30 kWh per day, so 200 kWh could run it for around 6-7 days. A washing machine uses around 0.3 to 1 kWh per load so with 200 kWh you could do between 200 and 600 loads of laundry.
You charge the battery with thermal energy from solar panels, heat pumps or other energy sources. According to Borg, the battery only loses 1 percent of its charge per day when not in use. The battery “will last at least 50 years,” co-founder Joost Spanjer told Solar Magazine. “Thermal storage is much more efficient than electrical storage. This is why we developed a thermal battery, sufficient to provide days of hot water to homes.”
According to Spanjer, the battery will mainly be charged during times when electricity prices are low or negative, for example when there is an overproduction of solar or wind power. When there is excess sunlight, the water will also be heated. Ultimately, the idea is also to use a large number of these batteries to balance the electricity grid, but “those are still futuristic ideas,” says Spanjer.
In the meantime, around 7,000 people have already expressed interest in the battery. Of these, around 60 have signed an intention to purchase, according to Spanjer. With the money from their deposits, the company invested to increase production. The first copies will be delivered in the spring.
The Borg home battery costs 15,000 euros including VAT. This does not include the costs of earthworks and installation. According to Spanjer, customers will be able to recoup these costs in approximately 5 to 15 years, depending on their energy consumption and prices.