- Amongst the private sector stock, 23% of the dwellings were identified through the use of Scottish House Condition Survey data as falling into Bandings of E, F and G on the A to G SAP scale used to rate the energy performance of dwellings in Scotland. This represents a total of 400,548 dwellings.
- The private sector overall performs worse in terms of its energy performance than the social sector, with the private rented sector having a higher proportion of dwellings amongst the F and G Bandings than other tenure groups.
- While 80% of all private sector dwellings are connected to mains gas, only 48% of those dwellings in the E F and G Bandings are connected, and amongst the worst group, i.e. Band G, only 19% of the dwellings are connected to a mains gas supply.
- Four policy scenarios were modelled to identify the least cost way to improve the energy efficiency of the private sector stock, and to assess the impact on various energy performance indicators:
- Scenario 1: improving all dwellings to reach EPC Band F
- Scenario 2: improving all dwellings to reach EPC Band E
- Scenario 3: improving all dwellings to reach EPC Band D
- Scenario 4: improving all target dwellings to move up one banding
- To achieve Scenario 1 would require a total investment of an estimated £18.6 million, with an average indicative cost of £627 per dwelling; Scenario 2 would cost an estimated £210.2 million, with an average indicative cost of £1,232 per dwelling; Scenario 3 would cost an estimated £1,070 million, with an average indicative cost of £2,672 per dwelling; Scenario 4 would cost an estimated £388.1 million, with an average indicative cost of £969 per dwelling.
- Scenario 1 has a mean payback period of 1.2 years, compared with 2.7 years for Scenario 2, 5.5 for Scenario 3, and 3.5 year for Scenario 4.
- Scenario 1 would produce fuel cost savings of £16.1million a year for the occupants; Scenario 2, £79.0 million; Scenario 3, £193 million; and Scenario 4, £111.6 million.
- Scenario 1 would achieve CO2e savings of 62,700 tonnes per year; Scenario 2, 361,700 tonnes; Scenario 3, 1.05 million tonnes; and Scenario 4, 605,800 tonnes.
- Scenario 1 would achieve a reduction of 204 m kWh in delivered energy annually; Scenario 2, 1273m kWh; Scenario 3, 3,569 m kWh; Scenario 4, 2,044 m kWh.
Email: Silvia Palombi