German sales of batteries to store solar energy at home may jump 59% this year as more residents seek a cheaper, renewable and more reliable power supply, industry association BVES said on Tuesday.

"We expect to be cracking the 1-million-unit level in 2023," said BVES, presenting an industry-commissioned study undertaken by advisory group 3Energie Consulting.

It forecast sales of 385,000 units, adding to the 650,000 reached at the end of 2022, and taking the total to 1,035,000.

German households have 2.65 million rooftop solar photovoltaic systems installed that produce power at home. However, before residential batteries were available to store the energy, the electricity produced by the panels went exclusively to the grid.

More families, typically in detached homes, are now buying batteries as they become cheaper.

Sector turnover could rise by 25% year-on-year to 3 billion euros ($3.23 billion) in 2023, up from 2.4 billion in 2022, when they had risen by 85%, 3Energie presentation slides showed.

Sales are also being driven by high energy prices in the wake of Russia turning off the gas taps to western Europe, homeowners' wishes for independence from centralised suppliers and increasing sales of electric cars, which can be charged with home-produced power.

"These drivers will be unchanged, resulting in further expanding growth; production facilities have been extended," the consultancy said about 2023.

There is also synergy among various renewable energy applications, it noted. Some 40% of households that use solar batteries also use electric pumps to provide home heating, many complemented by a buffer storage unit, and 36% of them also own an electric car.

Total sales in the household segment, which also includes heat pumps and buffer storage, rose 61% in 2022 to 7.1 billion euros and could climb 45% this year to 10.3 billion, it said, noting that tight labour supply to install the hardware was a problem.

Leading home battery vendors in Germany include sonnen, owned by Shell, Solarwatt, E3/DC, Senec, LG Chem and Tesla. ($1 = 0.9287 euros) (Reporting by Vera Eckert, editing by Miranda Murray and Sharon Singleton)