Solar & Tesla Powerwall Installation in Chesham, Buckinghamshire

The result

A 16.56 kWp solar and Tesla Powerwall system designed to significantly reduce grid electricity use for a high-energy household, while providing whole-home backup and capacity for future needs such as heat pumps.

The system is estimated to generate 12,203 kWh annually and deliver an approximate £2,520 financial benefit in year one.

At a glance

The customer’s objective

The homeowner already had a smaller solar installation receiving a Feed-in Tariff, but electricity bills remained high, particularly because of the amount of power used by an electric AGA.

After family members had previously used Phase Energy, the customer approached us to explore a much larger system that could reduce their reliance on grid electricity and provide greater energy independence.

Future plans to install heat pumps also meant the system needed to support the household’s likely increase in electricity demand.

The Phase Energy solution

We designed a 16.56 kWp solar PV system using 36 AIKO Neostar 460W panels.

The panels were installed on the south-facing roof of an older barn building on the property and paired with a Tesla Powerwall 3.

A Tesla Gateway was also installed to provide whole-property backup in the event of a grid power cut.

The initial installation uses one Powerwall 3, while allowing the homeowner to consider additional storage in future if their electricity requirements increase.

Why the system was designed this way

The customer wanted to use the barn roof, which provided a large south-facing area suitable for solar generation.

The array was designed to make effective use of the available roof space while maximising the input available to the Tesla Powerwall 3 system.

Tesla was selected in particular because the customer wanted whole-home backup through the Gateway, as well as the option to expand battery storage later if required.

With future heat pumps planned, the system was also designed with longer-term household electricity demand in mind rather than solely around current consumption.

Installation

The solar array was being installed on an older barn roof, so structural and weight-loading calculations were important before work could proceed.

The location of the solar array also created an electrical routing requirement. The main incoming electricity meter and Tesla Gateway were located away from the barn, so a small trench was required between the two buildings.

Groundworks were completed by one of Phase Energy’s subcontractors before the electrical connection was made.

The installation itself was completed in one day.