sonnen GmbH (proprietary name and abbreviated form: sonnen) is a company in the energy industry headquartered in Wildpoldsried in the district of Oberallgäu, Germany. It produces home energy storage systems for private households and small businesses. The company is considered the market leader in Germany and additional international markets. Moreover, it is the center of a community for supplying power from renewable energies.
Company development Company Christoph Ostermann and Torsten Stiefenhofer founded the company in 2010 as a GmbH (German limited liability company). The legal name of the company at that time was PROSOL Invest Deutschland GmbH. In December 2013, the shareholders' meeting decided to change the company name to sonnenBatterie GmbH,Bundesanzeiger, Commercial Register announcements on PROSOL Invest Deutschland GmbH, January 15, 2014, date of entry January 8, 2014. in order to adopt the name of its product range and to support the goal of internationalization.Statement by Christoph Ostermann in an interview with Mirco Sieg. See Since November 2015, the company has operated as sonnen, under which all the company's individual activities are organized.Statement by Christoph Ostermann in an Interview with Engelbert Hopf. See sonnenCommunity: Der mögliche Anfang vom Ende herkömmlicher Stromversorger. Ein Startup auf dem Weg zum 100-Mio.-Euro-Unternehmen. In: Markt&Technik, 27/2016.
Business development From 2008 to 2010See Daniel Pohl: Lithium iron phosphate: With the genes of a marathon runner. In: ees International. The Electrical Energy Storage Magazine, 1/2014, p. 33–37, here p. 36. Benjamin Reuter: Energie: Diese Heimbatterie soll den Strommarkt aufmischen. In: WirtschaftsWoche Green, June 5, 2014. Benjamin Reuter: Cleantech-Startups: Das sind die Champions aus Deutschland. In: WirtschaftsWoche Green, October 15, 2014. above all founder Torsten Stiefenhofer developed a home battery marketed from 2011 under the name of sonnenBatterie. As a solar battery, the product is geared especially to independent homeowners with a photovoltaic system. As of mid-2016, eight generations of this power storage system have been developed and marketed. Germany is the main sales market for the devices. The company also distributes the home batteries in Austria, Switzerland, United Kingdom, Ireland, Slovakia, Czech Republic, Italy, Netherlands, Sweden, Norway, the United States and Australia (current as of: October 2016).Henrik Petersen: Speicher sind keine Verbraucher. In: Photovoltaik, 4/2015, p. 66–71, here p. 70. sonnenBatterie mit neuen Rekorden. In: Allgäuer Zeitung, May 21, 2016. sonnenBatterie ab sofort auch in Norwegen verfügbar. Press release of the company of October 11, 2016. See also the Website of the Swedish company CRenergy, retrieved October 6, 2016 and the Website of sonnen, retrieved October 5, 2016.
Along with the renaming of the company to Sonnen GmbH, the company announced in November 2015 that starting in 2016, it would establish its own power community, whose members can trade power among themselves. Andreas Menn: Brüder, zur Sonne, zur Freiheit. In: WirtschaftsWoche, November 27, 2015. Since September 2016, owners of a sonnenBatterie, who are a member of this power community, can obtain electricity at a flat rate.
At the beginning of May 2017, TenneT and sonnen announced their plans to implement decentralized photovoltaic domestic storage batteries using blockchain technology to help stabilize the power grid and improve the integration of renewable energies. This offers a new source of income to sonnen customers who take part in the system. Furthermore, the planned blockchain pilot project is meant to improve and simplify the networking of storage batteries, photovoltaic systems and power grids, as well as make them more efficient. From an economic perspective, this technology and sonnen’s battery pool (sonnenCommunity) could reduce the redispatching costs for stabilizing the power grid.
Business fields Power storage Like other home storage systems, the sonnenBatterie from sonnen is also designed to increase the rate of own consumption of self-produced energy. Usually, a level of self-consumption of 30 to 55 percent can be reached with a photovoltaic system, when using smart-home functions. With a storage system, this rate is around 60 to 80 percent,sonnen strom auch nachts? In: Öko-Test Ratgeber Bauen und Wohnen 2015, p. 100–105, here p. 101. „Mit Speichern unabhängiger werden“. In: EffizienzHäuser, 6/7-2015, p. 48 f, here p. 48. as the self-produced electricity can be stored until it is consumed within the household. There is less need to source external electricity, especially mornings or evenings.
Since its market launch, the company has designed the sonnenBatterie as a fully integrated system. In addition to the battery modules, it has an integrated power inverter, a unit for power management, along with electronic meters for power consumption in the building, for photovoltaic power generation and for feeding power into the grid or power-sharing in connection with the sonnenCommunity. The power management system evaluates the user's consumption data and takes weather statistics into account, in order to determine the optimal time intervals for charging and discharging the storage system. Moreover, the sonnenBatterie can be combined with heat pumps, small wind turbines or combined heat and power plants.See also the technical specifications of the manufacturer on their website. For integrated use of sonnenBatterie, photovoltaic systems and combined heat and energy plants, sonnen works with Vaillant among others, see Heiko Schwarzburger: Endkunden virtuell vernetzt. In: Photovoltaik, 12/2015, p. 72–74, here p. 73.
The storage elements deployed are lithium iron phosphate batteries.See Reinhard Siekemeier, Ralf Ossenbrink: Solare Energie auf Vorrat. In: Sonne Wind & Wärme, 13/2011, p. 170–174, here p. 174. Uwe Bonnen: Funktioniert auch nachts und bei schlechtem Wetter. Neue Rezepte gegen steigende Nebenkosten. In: ew. Magazin für die Energiewirtschaft, 110 (2011), 26–27, p. 68 f. here p. 69. Michael Kerler: Öko-Strom aus dem Schrank. In: Augsburger Allgemeine, September 29, 2012. Sony is the main supplier of these components.Auf dem Weg zur dezentralen Energieversorgung. In: Straubinger Tagblatt/Landshuter Zeitung, June 21, 2016. The various models of the system differ above all in their rated capacity, expressed in kilowatt hours. In Germany, Sonnen was one of the first suppliers of lithium-ion batteries for stationary use in homes The article erroneously states that Sonnen was the first supplier. and is considered market leaderEnergy storage demand ramps up in Germany's residential PV market. In: Energy Storage Journal, Spring 2016, S. 37–40, here p. 39. in Germany and globally. Products are not distributed via wholesale trade but through selected specialty dealers.Ina Röpcke: Mit Leidenschaft verkaufen. In: Sonne Wind & Wärme, 10/2013, p. 94–97, here p. 95. From 2011 to mid-October 2016, 15,000 units were sold. Most went to homeowners, along with farmers and small businesses.Illustration of use in agriculture: Eine Batterie für den sonnen-Strom. In: Allgäuer Zeitung, May 22, 2014. And: Eigenstrom effektiver nutzen. In: Bayerisches Landwirtschaftliches Wochenblatt, June 27, 2014. Illustration of an application in the commercial sector: sonnenBatterie: Strom auf Vorrat. In: Hotel & Technik. Das Magazin für Hoteliers, Planer und Investoren, 6/2013, p. 54 f.
Community Since the first quarter of the year 2016, the company has organized the sonnenCommunity. It involves a power producer community of photovoltaic system operators (homeowners and small business owners), who share surplus power with one another. In order to fill any power gaps in times when there is less sunlight, biogas systems are also included. Operators of small wind generators can also supply the community with power.
The community combines three elements: the use of decentralized power generation, modern battery storage technology and digital networking of the participants. The concept is geared towards sonnen customers. The company grants prospective members a discount on the sonnenBatterie if they join the community. All members source power from the community at prices lower than from the grid. Moreover, sonnen handles the sale of surplus community power for them.Schwarmspeicher für die Community. In: ZfK Zeitung für kommunale Wirtschaft, January 11, 2016. See also Felix Austen: Das Stromdepot im Keller. In: Bild der Wissenschaft April 27, 2016. The sonnenCommunity. Energy freedom and energy community. In: pv magazine 6/2016.
By building up and expanding the community, the company hopes to boost sales of its sonnenBatterie. Besides, each community member pays a monthly fee to sonnen. The company in return handles the metering infrastructure and the software.
The number of members at the beginning of October 2016 was around 3,000 households. In May 2016, the company began building up the community in Austria. The launch of the Swiss customer platform is announced for the 3rd quarter of 2016.Swisscom Energy Solutions setzt auf Sonnencommunity. energate Messenger Schweiz, June 20, 2016.
Since September 2016, owners of a sonnenBatterie who are members of the sonnenCommunity can obtain electricity at a flat rate.
Shareholders In addition to the founders, several financial investors have equity stakes in the company (current as of: October 2016): In January 2013, eCAPITAL entrepreneurial Partners AG,Website of eCAPITAL. acquired a 30 percent share in the company for EUR 3 million.Benjamin Heimlich: „Jetzt ist die Zeit zu investieren“. In: VentureCapital Magazin. Special supplement Cleantech, 2013. p. 10 f. Andrea Martens: Wo weniger mehr ist. In: Unternehmeredition Private Equity / M&A, 2014, p. 6–14, here p. 14. The investment by Chrysalix SET Management B.V. (SET Ventures)Website of SET Ventures. and Munich Venture PartnersWebsite of Munich Venture Partners. was made at the end of 2014 as part of a capital increase of EUR 7.5 million, in which eCAPITAL also participated. Stefan Paravicini: Start-ups haben die Energiewende schon lange eingeläutet. In: Börsen-Zeitung, December 3, 2014. In mid-2015, Inven Capital, investiční fond, a.s.,Website of Inven Capital, investiční fond, a.s. a subsidiary of the Czech energy firm ČEZ, invested in the Allgäu-based company as part of an additional capital increase. The investment involved a high single-digit sum in the millions.sonnenBatterie erhält Geld von Investor. In: Allgäuer Zeitung, July 11, 2015 In June 2016, sonnen enlisted GE Ventures, the venture capital subsidiary of General Electric, as an additional investor. In October 2016, the company closed another funding round, resulting in EUR 76 million. All previous investors were involved. The Chinese corporate group Envision EnergyWebsite of Envision Energy. and Thomas Pütter, formerly CEO and ex-chairman of Allianz Capital Partners, were added as new investors. sonnen sammelt 76 Millionen ein. In: Handelsblatt, October 17, 2016. In February 2019, it was announced that Royal Dutch Shell would acquire 100% of the company for an undisclosed amount.
Management and human resources Up until the end of 2014, the founders managed the company.
At the beginning of 2015, there were changes in the management team. Hermann Schweizer replaced Torsten Stiefenhofer. The latter has since assumed the duties of Chief Innovation Officer. At the same time, the management team was supplemented by Oliver Koch, who had previously converted individual production of the battery systems over to series production. See also the entry on Oliver Koch in Bundesanzeiger, January 22, 2015.