Germany’s Top Residential Battery Company Ramps Up Its US Strategy to Rival Tesla

Is competition about to heat up in America’s home storage market?

Photo Credit: Sonnen

German residential storage developer Sonnen (formerly called Sonnenbatterie) is taking the fight for dominance in the home battery market to America.

On Wednesday, the first of 1,000 U.S. storage system orders left the company's production facilities in San Jose, California, according to company spokesperson Mathias Bloch.

Sonnen is aiming to get products to U.S. customers ahead of Tesla, its main rival in the residential battery market. Bloch said it hoped distributors could begin installing the systems, named the sonnenBatterie, before Christmas.

Meanwhile, a Tesla spokesperson said Tesla’s Powerwall “is in production today at the Gigafactory, and the very first units have been sent to North America, Australia and the DACH [Germany, Austria and Switzerland] region of Europe.”

It is not known when these first units will actually be installed. According to press reports, installations are not due to begin in Australia until February 2016.

Bloch said the end-user price for the U.S. sonnenBatterie system is $9,900, which is $745 cheaper than the equivalent product in Europe and includes a 2.5-kilowatt, 4-kilowatt-hour eco4 lithium-ion phosphate battery, an Outback Power inverter and control software.

In contrast, the Powerwall is priced at $3,500 for a 3.3-kilowatt, 10-kilowatt-hour unit. But this is the wholesale price to installers and does not include the cost of an inverter or control software.

“Tesla provides this price to the market to give consumers transparency when considering a Powerwall for their home, which will include additional costs for installation and possibly the addition or modification of solar equipment,” said the Tesla spokesperson.

Nevertheless, Tesla installation partner SolarCity has said it would offer the Powerwall plus inverter, control systems and installation for outright purchase at $7,140, or for $5,000 as part of a nine-year lease.

Based on the full purchase price, these figures appear to show Tesla significantly undercutting Sonnen in terms of cost per kilowatt-hour of capacity, at $714 versus $2,475.

But Bloch said the 10-kilowatt-hour Powerwall was designed for weekly cycling, giving it a lifetime of around 500 cycles, whereas the sonnenBatterie “can charge and discharge at least 10,000 times.”

He said it made more sense to compare the sonnenBatterie with Tesla’s 3.3-kilowatt, 7-kilowatt-hour daily cycling product, which wholesales for $3,000.

However, this product is not being commercialized in the U.S., so it is difficult to estimate what the all-in price would be in America.

In Australia, Sydney-based installer Natural Solar said the 7-kilowatt-hour Powerwall could retail for AUD$13,990 (USD$10,045) with a Fronius hybrid inverter, sales tax and installation thrown in.

On a per-kilowatt-hour basis, that is still about $1,000 cheaper than the U.S. sonnenBatterie.

“No one knows if Tesla is using a 100 percent DOD [depth of discharge] like we do. They don’t say it. If they had a DOD of 80 percent, you would have 5.6 kilowatt-hours. That changes this price a lot. And it still says nothing about the quality of the battery," said Bloch. 

Sonnen intends to give Tesla a run for its money in key residential energy storage markets worldwide.

In the U.S., Sonnenbatterie has signed up 30 distributors and plans to sell and ship "several thousand units in 2016,” said Bloch.

The company is already the dominant battery system vendor in the German market, where it will begin connecting customers to an energy trading network, sonnenCommunity, in the New Year.

It has also opened an office in the U.K. and recently extended operations to Italy, where it has sold “several hundred” units, according to Bloch. An Australian launch is imminent, he said.

Tesla plans to target the same markets. “We are not disclosing discrete order numbers; however, we have seen tremendous interest from around the world. Powerwall is a global product and launch markets are Australia, North America including Hawaii, and the DACH region of Europe," said the spokesperson.

Earlier this month, Vermont-based Green Mountain Power announced it will offer the Powerwall to customers, with three purchase options and shipments starting in January.

“Customers who share access of the battery will pay about $37.50 a month with no upfront cost, which equals $1.25 a day,” said the utility.