Background Articles and Features

Smart Plug/Play Photovoltaics with Storage Capabilities – SolMate by the Austrian Start-Up EET

Guerilla plug-In photovoltaics is a broadly discussed topic nowadays and regulations show a clear tendency towards liberalization. A new player – the Start-Up EET – came up with an innovative system, that is equipped with a measurement technology and a small puffer storage compound to upgrade the guerilla device to a smart and safe energy providing system.

EET - Efficient Energy Technology GmbH is one of the finalists of the ees Award, which will be presented as a part of ees Europe in Munich on May 15, 2019 at 4:30pm.

SolMate – the idea behind the system

SolMate is a photovoltaics and storage system, that can be installed by anyone by simply plugging it into a household socket. The small power plant consists of five lightweight, semi-flexible photovoltaic panels and a small storage device. The panels are put on a wall, balcony, fence, etc., connected to the storage device and the storage is plugged into a regular wall socket.

SolMate produces renewable electricity and provides it to the household when it is needed. The intelligent power injection is based on the patented measurement technology of EET. This innovative measurement technology allows SolMate to produce approx. 25 % of the energy consumption of a regular household in Europe, renewably and independently.

The innovation core of the start-up is the patented measurement technology with the working title NetDetection (see highlighted in blue in Figure 1). It is a high frequency measurement, which continuously measures the grid of the household, therefor being able to detect load sheddings. Based on the NetDetection technology, SolMate optimizes the power injection of the small photovoltaic system according to the household’s load.

Fast growth and prominent support by Mr. Klaus Fronius

EET – Efficient Energy Technology – was founded on Mai 9th 2017 by Florian Gebetsroither, Christoph Grimmer and Stephan Weinberger. The young Start-Up is a Spin-Off of Graz University of Technology. It is based on a patented non-invasive measurement technology, which is able to detect the power consumption within a household. After only a few months of research and development, EET raised the attention of many interested. The first prominent supporter and investor Klaus Fronius joined EET in December 2017 and is an active player on the roadmap towards commercialization of SolMate. The dynamic within the Start-Up caught even more fire after that, the team grew rapidly from only 3 founders to 17 team members in less than a year.

Go2Market in 2019

The first small series of SolMate is manufactured right now and ready for shipment in the second quarter of 2019. The system will be available in Austria, Germany and Switzerland. The market perspectives of photovoltaics in general and plug-in solutions in particular show a high growth potential. Several market surveys indicate annual growth rates of up to 40%. One of the most important aspects is the regulative situation, which is getting more and more suitable for plug-in solutions in Europe.

SolMate does not need a smart home base. However, the hardware can be implemented in future smart home solutions.


SolMate ist no ordinary plug & play system, but rather a complex solar power plant with some distinguished features:

The main benefit originates from the elimination of the necessity of hiring a fitter. SolMate is the first storage solution that can be installed by simply plugging it in, without having a building site at home.

Due to the smart measurement technology all of the produced solar power can be used within the household, thus exhibiting a self-usage rate of 100 %.

Over the lifetime of a SolMate, about 25 % of an average household’s electricity costs can be saved, as well as 6700 kg of the greenhouse gas CO2. Furthermore, when considering a full life cycle assessment, the total environmental impact regarding pollution is about 80 % less compared e.g. to the German electricity mix.

In the event of a blackout, the system can also provide emergency backup supply via an integrated power socket. SolMate contains a second inverter module, which enables a highly useful off-grid application. This means: the system is not only capable to work without a power grid, but rather generates its own offline grid. Therefore, SolMate can also be used to provide electricity to hats, gardenhouses etc...

The transition metal cobalt has been a delicate topic over the last years, because of the harsh and difficult mining conditions used for its winning. SolMate uses a lithiumironphosphate storage technology, rather than the common lithium-ion accumulator technology and does not need any cobalt in order to work. In addition, lithiumironphosphate exhibits enhanced temperature behavior and has a higher lifetime than other battery systems.

The device contains a WIFI connection, which is used to connect it to a server, making all data available for the smart phone app. Additionally, the connection can be used to set applications and control the output power. Hence, SolMate is compatible with Smart Home installations, although it’s not necessary for the system in order to be smart.


Jan Senn

Sales & Marketing

EET - Efficent Energy Technology GmbH

The ees International Magazine is specialized on the future-oriented market of electrical energy storage systems, not only from a technological-, but also a financial and application-oriented point-of-view. In cooperation with ees Global, the ees International Magazine informs the energy industry about current progress and the latest market innovations.
Contact: Xenia Zoller - zoller(at)