Constantine

System Installed  We have a 6 kW PV array and 15 kWh of usable battery storage.

Household We have a fully electric house, heat pump, water heating, induction hob etc. We also have an electric car.

Household usage We burn approximately 8 kWhs a day during the summer and 25 kWhs a day during the winter. We drive approximately 10,000 miles a year in the electric car. In total the house uses approximately 6.5 mWhs of electricity a year and the PV panels produce approximately 6 mWhs of electricity a year.

Installation

Lifestyle changes During the winter when PV power is limited we charge the batteries from the grid at night for 9p per kWh, we also time our water heating and washing to be on at night.

Solar Generated & stored In total the house uses approximately 6.5 mWhs of electricity a year and the PV panels produce approximately 6 mWhs of electricity a year. During the winter the house is using about £1.30 of electricity a day plus standing charge. During the summer the PV panels supply almost all the power the house needs so we only pay the standing charge.

SEG We are on Octopus Go electricity tariff paying 9p per kWh at night and 30p per kWh during the day. We also receive 8p per kWh for our surplus electricity returned to the grid.

EV During the summer months we have enough surplus energy to keep the car fully charged, meaning the fuel costs per mile are £0.00 for those months. During the winter months we charge the car at night for £0.09 per kWh which makes the fuel costs about £0.02 per mile. We estimate we now spend about £200 pre year to drive 10,000. This cost us £1,700 in diesel in the previous car.

Expectations Vs Reality 

Summary We estimate the savings across the year are more than £1,550 for energy use in the house!