sonnen stores and trades regional green energy among connected households, alleviating bottlenecks in the power grid and offering digital proof of energy transactions via blockchain

sonnen makes use of excess green energy, which would otherwise be lost as a result of the curtailment of PV or wind power plants, making it possible to relieve common bottlenecks on the regional distribution networks. Each kilowatt-hour used for this will receive a digital fingerprint via blockchain.

Wildpoldsried, 3rd May 2018 - With the "Flex Platform", in Germany, sonnen is presenting a completely new approach, by which excess green energy can be utilized by a network of sonnenBatterie systems.

By storing excess green energy, sonnen is helping to solve a known issue with renewable energy both on a regional basis and a local site by site basis known as the network bottleneck. Due to fluctuating and intermittent energy production from sun and wind sources, there are often periods of time in which far more electricity is produced than is consumed. When the utility networks can no longer absorb this surplus electricity or direct it elsewhere, congestion occurs, much like a a traffic jam. In order to  prevent network overload , wind turbines, for example, have to be throttled or completely switched off. The enormous cost of these interventions indirectly impacts the price of the electricity in Germany, and clean energy has to be discarded.

With the new Flex Platform from sonnen, the distribution system operators (DSOs) responsible for managing the regional electricity networks will be able to intelligently solve this problem on-site. Instead of curtailing excess wind power, it will be distributed to or stored in an array of individual sonnenBatterie systems across the respective region. There is great interest in this solution

“The distribution system operators have to find a way to compensate for the fluctuating renewable energy production in their area. With our new Flex Platform, we can offer them an intelligent tool to achieve this. We have already commenced a collaboration with one of the largest German distribution system operators and we are very optimistic that more will follow soon," says Jean-Baptiste Cornefert, Managing Director of sonnen eServices.

The new Flex Platform is based on the intelligent software that is an integral part of each sonnenBatterie, which has proven itself in of thousands of households in recent years. This allows the sonnenBatterie to be controlled in such a way that it only charges up when the energy production of photovoltaic system is so high that the law requires it to be curtailed. This is typically the case at noon. This way, the household can benefit from solar energy which would otherwise be lost without intelligent storage.

Networked across thousands of systems, sonnen is able to transfer the intelligent charging behaviour to its battery storage department, which can store excess energy such as that from wind turbines, on a larger scale.

In order to prove and document the storage transactions between wind turbines and each individual sonnenBatterie in a tamper-proof manner, the Flex Platform makes use of blockchain technology. To this end, sonnen has initiated a collaboration with the "Energy Web Foundation" (EWF). This gives each individual, green kilowatt-hour a digital fingerprint when it is stored, saving the energy rather than having it leave the region. The technical integration has been successfully implemented by sonnen using the Energy Web Origin app. This app is based on the EWF test network, Tobalaba. This is an Ethereum blockchain platform, which is adapted to the market conditions of the energy sector.

As a result of the networked sonnenBatteries, a large capacity of stored green energy resources are available to a variety of distribution networks across Germany through the intelligent control of sonnen’s battery network using the control room of the "sonnenCommunity. In this way, adjustments can be made to alleviate local grid bottlenecks. Distribution system operators thus have the ability to use the Flex Potential and the sonnen network in a targeted and localized manner, putting excess green energy to good use.

Benefits also exist for the sonnenBatterie owners. When necessary, they can charge up their storage system with excess wind power, which is guaranteed to come from their region. This means that they also have clean energy stored away to power their homes, even when the sun hasn't shone for a few days. By doing so, they help consume excess renewable energy created in their region.

With the newly introduced "sonnenCharger” even electric cars can be added to the network. This smart solar EV charger can maximize the use of local resources, as vehicle owners can set their charging time automatically to coincide with the time of surplus generation.