Energy SourcesEnergy consumption is commonly measured and costed in UNITS.
1 Unit of energy is consumed by an appliance with a power output of 1kw running for 1 hour.
| Fuel | Quantity used per hour | Cost
£ | Energy Used per hour | Unit Equivalence | Approximate Cost per Unit
£ | | Electricity | 1 kW | 0.1316 | 3600kJ | 1 unit | 0.1316 | | Gas | 1 m3 | 0.43 | 40100kJ | 11.139 units | 0.0387 | | Oil | 1 Litre | 0.5818 | 43200kJ | 11.94 units | 0.049 |
Source: Department of Energy and Climate Change, June 2012 Quarterly Energy Prices
Unit costs are the average retail value of direct debit tariffs for UK suppliers.
Air Change Rates| Room | Rate (ChangesperHour) | | Living room | 3 - 6 | | Bathroom | 6 - 10 | | Kitchen | 15 - 20 |
Heating Season
The figures below are suggested usage of a domestic central heating system for the purpose of calculations. Actual figures for individual households will vary considerably and probably be significantly greater.
| Central Heating in Use | Sept (part), Oct, Nov, Dec, Jan, Feb, Mar, Apl, May(part) | 240 days approx | | Hours of use | 7 - 8:30, 4:30 - 10 | 7 hours | | Total Hours | | 1680 hours |
| Month | Min Temp
deg C | | Sep | 9.5 | | Oct | 6.5 | | Nov | 3.5 | | Dec | 1.3 | | Jan | 1 | | Dec | 1.8 | | Mar | 2.4 | | Apl | 3.7 | | May | 6.5 | | Average | 4 |
Radiator Heat Output
| 