- Step 1 in the Journey to Energy Freedom was buying an energy meter.
- Step 2 was replacing all light bulbs with LEDs
- Step 3 was installing radiator heat reflectors
- Step 4 <– We’re now at step 4. I’ve installed attic insulation, and the figures are in:
Step 4 Summary:
- Capital Cost: €598
- Payback: 2.93 years
- Saving per year: €204.40 per year | 2,555kWh | 587.65kg CO2
- 25 year Saving: €4,512 | 63,875kWh | 14,691kg CO2
Heating our average house in a cool (but not excessively cold) country with a natural gas boiler costs €693 per year, consuming an average of 29kWh of natural gas per day. That means heating costs stack up against other energy expenditure like this:
What it costs to heat your house, power it, and power your car.
In Heating a Building, we saw that killing pesky heating bills starts is actually pretty easy, and it starts with cutting down heating requirements. This graph compares all heating measures:
Cost and Energy Savings of different heating options over natural gas.
Insulation stacks up pretty well in the graph – with the capacity to save 10 kWh of heat energy required in your house per day, or save about $730 per year in a large house.
This is a useful image of the different places insulation can go:
Potential Insulation Locations
I started with attic insulation (heat rises, so this is the best place to start with insulation).
The figures come to:
I installed Earthwool Loft Roll 44 (Combi Cut) Loft Insulation in the attic for the job. The thermal conductivity of which is 0.044 W/mK. A 10M^2 roll came to €26. The floor space is 23 M^2, so the capital cost was 26 * 23 = €598. The insulation stops 7 kWh per day leaking out of the ceiling of the house and into the air. At €0.08 per kWh of gas, that comes to 7 * 0.08 = €0.56 per day, or 365 * €0.56 = €204.40 per year. This means a payback of €598 / 204.4 = 2.93 years, and a 25 year payback of €204.4* 25 = €5,110.00 – €598 = €4,512.00. Not bad at all! That’ll pay for a wood burning stove with a back boiler to provide the remaining heat required without needing to pay for gas or oil.
Gas emits .23kg CO2 per kWh from a gas boiler with reasonable efficiency, so the yearly saving is 2,555 kWh of gas saves 2,555* .23 = 587.65kg CO2 per year, or 587.65 * 25 = 14,691kg CO2 over 25 years. So for an investment today of €598, we can save €4,512 over the next 25 years AND feel much more comfortable in our house? This is a step you’ll want to take!
Summary:
- Cost: €598
- Payback: 2.93 years
- Saving per year: €204.40 per year | 2,555kWh | 587.65kg CO2
- 25 year Saving: €4,512 | 63,875kWh | 14,691kg CO2
References: