Tenant electricity enables the economic marketing of photovoltaic electricity to customers directly on site. The combination of tenant electricity and charging infrastructure in particular offers significant advantages. An article by our tenant electricity partner Solarize Energy Solutions GmbH describes how tenant electricity and intelligently controlled charging stations complement each other and how smart software guarantees high margins. The article published in ew – Magazin für Energiewirtschaft explains how to set up the corresponding metering concepts and what requirements there are for the software solution.
Charging infrastructure with optimization platform
The integration of charging infrastructure into a tenant electricity model has several advantages. First and foremost, it increases the direct consumption rate and therefore the profitability of the PV system. At the site in the east of Karlsruhe, 22 charging points for e-vehicles are balanced with their own electricity tariff via the Solarize software. The charge point operator (CPO) is Badische Energie-Servicegesellschaft mbH (BES), a subsidiary of Stadtwerke Karlsruhe.
The entire charging infrastructure is managed as a tenant electricity participant with its own tenant electricity meter. The optimization of charging processes by the company InnoCharge is particularly interesting. The charging optimization solution continuously creates price-optimized charging plans and decides in the background when to charge and at what power during the vehicles’ downtime. “This has the advantage that any surplus PV is primarily charged into the vehicles, otherwise charging takes place at times with favorable dynamic prices, expensive load peaks are avoided and there are no power bottlenecks within the property,” explains Manuel Lösch, Managing Director of InnoCharge. “This allows us to optimize the cost side of the BES, as the charging customers have a fixed kWh tariff.”
Digital energy management of the future
For this purpose, the charging points are connected to InnoCharge’s own smart charging platform – a kind of “charging conductor” – via the Open Charge Point Protocol (OCPP). The charging points are initially configured once on the platform. It then takes care of data collection, process control, the necessary forecasts, the predictive charging optimization itself and the implementation of the charging plans by the vehicles in 24/7 operation. This charging optimization makes sense, as the usage behaviour at the iWerkx building corresponds to a classic office location: the vehicles are plugged in in the morning and unplugged again late in the afternoon. This means they are parked for around eight hours, but only have to charge for a fraction of that time.
For the interaction between charging infrastructure and tenant electricity to work, a well thought-out metering concept is required: An official metering point must be installed upstream of the charging infrastructure so that the charging infrastructure can be supplied by the tenant electricity supplier in accordance with the Technical Connection Conditions (TAB). This meter measures what proportion of the electricity consumed in the charging infrastructure comes from the PV system and what proportion comes from the grid. This is crucial for correct billing. The Solarize software takes care of this. InnoCharge provides the optimization, including user-specific recording of the individual charging processes (via RFID card).