Bungalow - Air Source Heat Pump, Solar PV & Tesla Battery Storage

Existing Homeowner's Project

Client: John Flatt - Cornwall Date: 15th April 2019 Category: ,


Our customer wanted to further reduce his energy costs. He was considering adding more panels and battery storage to the existing solar PV array, and wanted to use all the free energy he would be generating. The VAT rate for the battery can be reduced when purchasing with solar PV panels. 

Heating and hot water was provided by a gas combi boiler. 


We completed a home heating survey, identifying how much heat and hot water was required. 

Our specialist heat pump design software confirmed how much electricity the heat pump will consume when producing all the heating and hot water for the property. This enabled the client to install solar PV and battery storage with a better understanding of how much energy it was going to save for him. 

We installed a Mitsubishi Ecodan air source heat pump system to replace the old gas combi boiler and upgraded three radiators to meet the desired room temperatures. 

Free heating and hot water will be produced with excess free electricity that is routed to the heat pump by an Eddi smart switch. This was installed by our solar PV partner as part of their installed of the new panels and battery storage. 

The client has a Google Nest smart thermostat system to control when the heating is switched on. The Mitsubishi Ecodan responds to this thermostat to provide heat to the radiators. 


  1. A warm house with very low energy costs. 
  2. Total reduction in heating costs of 30
    – 12% by replacing the gas boiler
    – 30% with solar PV 
  3. Domestic renewable heat incentive (RHI) tariff payment of £8321.00  
  4. Total carbon savings of 45%
    – 30% by replacing the gas boiler
    – 45% with solar PV 

Installation Photos

Get in touch about your project