There are 4 varying grades of housing stock to consider;

  1. Older Stock which needs upgrading wherever possible.
  2. Current Stock already up to a reasonable standard but can be further upgraded.
  3. New Current Stock.
  4. New – Future Build.

There are 3 general types of heating ; Boiler (Condensing or Non-Condensing)
Hybrid (Air Source + Boiler) and Renewable.
For this example, which is for guidance only, we will use Air Source as the renewable technology.

Efficiency Performance Stages

_ Current New Non-Condensing New Condensing Hybrid Air Source
1. Older Stock 70% 87% 90% 278% –
2. Current Stock – 87% 90% 278% –
3. New Current – – 90% 278% 270%
4. New/Future Build? – – – 278% 270%

*Efficiency does not always mean saving money nor getting the heat you need

Estimated running costs – Please note the following points;

  1. First line at 50p per litre fuel – second at 40p per litre fuel.
  2. Based on the same net heat to property.
  3. The higher the upgrade of property, the lower the requirement of heat will be for all and some costs will then vary more.
  4. Condensing A rated as 90% eff. – NonCondensing as 86%.
  5. Elec. calc. at 14p per unit.
  6. Cop for Hybrid ( A/S ) = 3.25, for Air Source = 2.7, for Ground Source = 4.0.
_ Old Non-Condensing New Non-Condensing Condensing Hybrid Air Source Ground Source
(50p) 1428 1162 1111 911 1037 700
(40p) 1120 911 880 867 1037 700

As more and more properties become better constructed, we will naturally head towards renewables, increase efficiency, reduce demand, therefore fuel use and our carbon footprint will be much lower.
The challenge is to match the available heat technologies with the current housing stock to give best value. 

RENEWABLES     –     Are we ready for them?     –     NOT YET!