Running a 7.65 kWp PV power plant since 2015 and following the daily production cycle (historic data) is central to the use of electric energy in the household. The yearly total production of more than 7000 kWh is used for electrical devices (household appliances, TV, computers, and lights), with a local consumption of ca. thirty percent. Since 2018, using an EV (BMW i3) has the total yearly consumption increased to ca. 5000 kWh.
Having spent the last years at the job doing detailed calculation and simulation of battery systems based on consumption data, it is clear, that private use of storage systems is currently an expensive hobby. At least one thousand € per kWh storage is too expensive, especially when batteries for cars are getting below $ 100 per kWh (Tesla).
Driving an EV for more than a year now, I will never go back to an ICE. The biggest challenge are the various charging cards, and inconsistent charging rates (per minute, per kWh, fixed rate etc.). Using the charging station at home is very convenient – most of the time we do not need to charge the car at a public charging station at all. Only at longer journeys it is necessary to recharge the EV.
When using EV’s becomes more common (also for transportation) smart charging solution will be essential – optimal charging, based on PV production, charging time (day, night), and using local storage systems, is an interesting problem to be solved in the near future.