J & M: saving from day one
J & M recently had a 15kWh system installed in their detached garage. The location was perfect: clear, accessible and near to the mini consumer unit already providing power in the garage. Connecting into the garage consumer unit meant we didn’t need to switch off power to the house at any point, which minimised disruption.
The biggest challenge was wiring in the sensor (CT clamp) that measures how much current is being imported from the grid at any given moment. Existing legislation requires this device to be hard-wired between the main incoming supply and the inverter so we needed to find a suitable path for it. Fortunately, it could follow the external wall of the house and then feed under some external steps to reach the garage to connect into the battery system.
Ideal space cleared and ready, easily meeting the required 1.8m x 0.6m x 0.5m and located next to the mini consumer unit already supplying the garage.
The route the sensor cable needed to take: from near the main fuse board location (blue arrow, right-hand side) along the brick work before feeding under the steps on the left.
Finished installation and commissioning:
Once we wired in the system and tested a controlled charge and discharge cycle we could complete the system handover in person before finalising the system set-up remotely. J & M had already switched to a competitive time-of-use tariff that doesn’t require them to own a specific vehicle: it simply provides 5 hours of low-cost electricity every night that they can use to charge up their battery. So straight from day one they’ve been making savings on their electricity usage. At the time of writing they’ve shifted >90% of their imported grid electricity into off-peak pricing whilst not having to adjust when they use electricity in their home.
Check back in for an update later this year when we’ll look at how much they’ve managed to save in practice.
The completed installation ready to arbitrage electricity prices and save money every day.