Performance evaluation

• The Wondrwall home used net 4921 kWh of energy in total, compared to the control home, which used 9933 kWh of energy. Net energy consumption for the year was 50% lower for the Wonderwall house. CO2 emissions were reduced from 1870kgCO2 to 602kgCO2, a reduction of 68%. The energy costs were reduced by 55%, from £1893 to £851.
• The Wondrwall home generated solar electricity from the 10 panel PV array, generating 3.4kWp. This generated 2861 kWh of electricity, which contributed £838 of the cost savings, along with generating 998kWh that was exported to the grid, generating a small revenue of £43 over the 12 months period. Additionally, 392 kWh of off-peak electricity was purchased for battery storage and use during peak hours. This generated a saving of £864 compared to purchasing the electricity at full peak costs.
• The customers have been “astounded” by how low their bills have been in the summer months (they had not yet experienced a winter).
• They say the house’s intelligent living system is unintrusive and that once they adjusted to the changes it’s been like living in any other homes. “We’ve had a few teething problems, like some ‘white noise’ from the light switches and sometimes the automatic light sensors can be too sensitive or not sensitive enough.”