Backwell Common

The Project.

An existing client of ours approached us to see if we could help reduce his high electricity bills. The property in question is a large house with a pool room and hot tub and as such has a high electricity demand.

With a large roof space and plenty of space for a Solar PV system we discussed installing a large solar array to offset their bills and raised the option of a battery storage system to capture the excess production to be used overnight.

The Solution.

Our solution was to install 2 solar arrays on 2 different roof aspects to extend the period of time that daylight would usefully produce electricity and maximise the roof size of the client. We proposed a 6kW array consisting of 18 Viridian in roof solar panels each capable of producing 335W.

This array would be connected to a 6kW Solis hybrid inverter and a battery storage system in the house to store excess production and use it overnight.

The client chose an in roof solar system due to the aesthetics of the system over an on roof system, this meant we had to remove existing tiles and replace them with the Viridian Fusion panels and flashing system.

The Installation.

Completed over a period of 2 days the panels were installed in 2 arrays of 9 panels with DC cabling back to the inverter cupboard. The 2 arrays on different roofs mean that space has been maximised and energy can be produced for a longer period of time throughout the day as the sun moves through the sky.

 The client has 15kWh of storage for additional generation, minimising the amount of export power and hoping to store enough energy to last the night. The customer was aiming for at least a 50% reduction in energy bills.

Value.

Since installation the system has produced roughly 50% of all electricity required for what is a high usage property. The cost of the system was roughly £15,000 including scaffolding and a new consumer for the AC power supply to the inverter. The estimated annual savings for the system are £1,429 with a payback period of 8 years. What this doesn’t take into account is the flexible energy tariffs on offer, for example this client is using low tariff rates to charge the battery in order to use cheap electricity through the day when solar generation is limited so payback could end up being shorter.