Pilot set-up for home batteries – Dutch Homeowners’ Association

The Dutch Homeowners’ Association (Vereniging Eigen Huis, VEH) tested home batteries in thirteen households. CE Delft analysed twelve months of data to examine:

• how home batteries perform in practice;
• the cost savings or revenues they generate;
• their potential role after the phase-out of the net metering scheme, with a forward-looking assessment based on historical data.

Based on seventeen hypotheses formulated by Vereniging Eigen Huis, the main conclusions are:

1. Home batteries cannot fully compensate for the loss of the net metering scheme. After the abolition of net metering, household energy bills increase even when a home battery is installed. In some cases, the battery can create enough revenue to pay itself back, but the additional revenues are insufficient to offset the higher energy bill. Moreover, in several pilot set-ups the battery is not paid back.
2. Home batteries increase self-consumption. A well-sized home battery can increase self-consumption by around 30% on average. In one representative pilot set-up, self-consumption increased from 35 to 68% with a 5 kWh home battery. For households with much higher electricity consumption and solar PV generation, a larger home battery is required to achieve a similar increase in self-consumption.
3. Self-consumption combined with the day-ahead market is the most future-proof revenue model, but its profitability remains uncertain. In recent years, the imbalance market provided the most profitable business case, but these revenues are not future-proof. Revenues are declining because more batteries are becoming active and because, after the abolition of the net metering scheme, energy tax must be paid on electricity traded via the home battery. As a result, historically expected payback periods are no longer realistic. After the phase-out of net metering, self-consumption becomes the primary revenue model, supplemented by smart charging and discharging based on day-ahead market prices, particularly in winter months when on-site solar generation is limited. Depending on future developments, a home battery may still be paid back, but the loss of net metering cannot be compensated. Two pilot set-ups show payback periods ranging from 6.5 to 22 years, with strong dependence on household characteristics such as energy consumption and demand, electricity contracts, future energy price developments, and policy.