What would be the expected CO2 emission reductions in a Touchwood house relative to a standard house?
The idea is to meet the Passivhaus standard, which aims to reach a 90% reduction in heating demand through minimising heat loss through the building structure. We then aim to supply the remaining 10% either through solar gain, a small heater in the HRV system, or a log stove. Log stoves produce 96% less CO2 than gas, and wood pellets 93%. This massive saving is due to wood having no net change in global CO2 concentrations since the CO2 released was only absorbed by the tree recently. The small perecentage emitted is due to the processing / transportation of the fuel. It follows from this, that we achieve a 90% saving on demand and then a 93% saving on supply, so a 99% reduction on CO2 emissions overall. Note this is for heating. For hot water provisions we recommend a large solar panel for the summer, followed by a low carbon option for winter – such as pellets, log boilers or similar – if the location allows. The solar would provide around 55% of demand, with pellets / logs providing
