Figures from page 4 of ‘Make Your Self Build Self Sufficient’:
| House size | kWh/yr | Oil cost/l | Oil cost/kWh | Oil boiler efficiency | Annual oil running cost | HP SPF | Elec cost/kWh | Annual GSHP running cost | Running cost saving | Renewable kWh/yr | RHI tariff p/kWh | RHI Income | % fuel saving |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Medium | 12500 | £0.51 | £0.06 | 92% | £778.53 | 449% | £0.16 | £346.23 | £432.31 | 9716 | £0.21 | £2,029.67 | 56% |
| Large | 18500 | £0.51 | £0.06 | 92% | £1,152.23 | 427% | £0.16 | £530.85 | £621.38 | 14167 | £0.21 | £2,959.49 | 54% |
| Very Large | 30000 | £0.51 | £0.06 | 92% | £1.868.48 | 394% | £0.16 | £925.40 | £943.08 | 22788 | £0.21 | £4,760.41 | 50% |
Figures exclude inflation.
Figures from page 10 of ‘Make Your Self Build Self Sufficient’:
| kWh/yr | Efficiency | kWh/yr | Fuel cost | Annual running cost | RHI tariff | Ren kwh/yr | RHI income/yr | Maintenance | |
|---|---|---|---|---|---|---|---|---|---|
| Gas | 18500 | 92% | 20109 | 0.04 | £840.54 | 0 | 0 | £114 | |
| Oil | 18500 | 92% | 20109 | 0.06 | £1,152.23 | 0 | 0 | £100 | |
| LPG | 18500 | 92% | 20109 | 0.06 | £1,260.82 | 0 | 0 | £100 | |
| ASHP | 18500 | 401% | 4613 | 0.16 | £738.15 | 0.11 | 13,887 | £1,487.25 | £50 |
| Biomass boiler | 18500 | 85% | 21765 | 0.06 | £1,231.88 | 0.07 | 18,500 | £1,272.80 | £250 |
| GSHP | 18500 | 427% | 4333 | 0.16 | £693.21 | 0.21 | 14,167 | £2,987.77 | £50 |
Figures based on a large new self build home or medium sized renovated home. 18,500kWh/yr.
Figures exclude inflation.
Energy costs are based Feburary 2020 costs, provided by Nottingham Energy Partnership (NEP). Costs for electricity heating are not provided by NEP – derived from an average of the ‘big’ six electricity prices for Febtuary 2020 and excludes any standing charges.
Gas based on BG Homecare 100. https://www.britishgas.co.uk/products-and-services/homecare/homecare-100/
Biomass based on 4800kWh/tonne at £235 per tonne.
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