Germany’s residential storage system maker Sonnenbatterie will continue its push into the US, partnering with Sungevity, the residential PV installer founded by environmental activist and cleantech entrepreneur Danny Kennedy.
Sungevity, which offers upfront payment, loan and financing as well as third party leasing options for its customised systems, will begin offering Sonnenbatterie’s systems to its customers in Europe as well as the US. According to Sungevity, this will start happening in the second half of this year.
While economic drivers and metrics for the desirability of storage systems vary throughout the different regions of the US depending on market design and regulation as well as technical parameters, Sungevity said its customers will benefit by being able to self-consume their solar-generated power and give them access to uninterruptible backup power as well as enjoying “reduced costs”. Backup appears to be a growing concern in the US, with grid outages and recent extreme weather events over the past few years stirring up fears.
Cosmin Laslau, an energy storage expert at Lux Research, explained to PV Tech Storage that while a cash value was hard to put on the peace of mind offered by storage, it is nonetheless a driver for adoption in the US. Talking ahead of an expected announcement by Tesla today on its efforts in energy storage, Laslau said this aspect of storage's appeal seems to be growing.
"It’s [solar storage is] not just about solar integration and making that more efficient, it’s also about backup which is hard to place value on for a buyer who wants the peace of mind associated with that, especially as we see more flooding and other natural disasters, homeowners do buy it for that peace of mind," Laslau said.
Incidentally, a spokesman for another major US residential installer, SolarCity, which has also begun deploying energy storage units under pilot programmes, recently told PV Tech that his company considers many of these, including Hurricane Sandy, to be directly linked to climate change issues.
“Whether it’s commercial or residential, customers are very interested in backup power. There’s been an increase in weather related outages, we believe they’re climate related outages,” Jonathan Bass said.
“Hurricane Sandy was a prime example a couple of years ago. There’s more and more interest in backup, as the cost of the batteries comes down, it becomes more and more economical for customers, more and more attractive.”
Sonnenbatterie’s systems incorporate Sony Fortelion batteries and earlier this month announced that its newest range of lithium-ion storage systems can withstand 10,000 cycles of charge and discharge, adding what the company claimed is a “very long lifetime” to the systems. The German company offers storage units for homes and to some extent businesses as well, launching in 2011.
It had sold around 4,000 units in Germany by the beginning of this year, from estimated total sales in the country of around 15,000, giving Sonnenbatterie a big share of the early market.
From there, while PV system sales are on a definite recent trend of decline in Germany’s rapidly changing market, the proportion of systems sold with energy storage attached has risen, as have standalone sales of PV storage. Market research firm EUPD has predicted Germany could see 100,000 household storage systems installed by 2018.
EUPD’s CEO Markus Hoehner recently also told PV Tech that end customers to Germany’s solar installers are becoming increasingly aware of storage options, especially as subsidies disappear and self-consumption of onsite generated solar becomes more attractive. An EUPD survey shows that while only 47% of end customers had considered installing storage before 2011, the figure had risen to 70% for new customers in 2014. Similarly, before 2011 only 4% of residential PV customers had installed a storage system, while in 2014 the figure leaped to 20%.
In terms of new business models for storage in Sonnenbatterie’s home continent, the company said it is currently trialling two programmes in Germany to aggregate the output of a large number of connected residential and commercial systems to form so-called virtual power plants. One trial will see a 100% renewable energy powered utility company aggregating Sonnenbatterie storage systems to compete in the country’s grid-balancing frequency regulation market, while the other will see the company use a virtual power plant to join the retail electricity market.