Fuel poverty is not only worse in rural Scotland than in urban Scotland, it also has different characteristics. For example, in urban areas 92% of those classified as income-poor are not classified as fuel-poor while in rural areas only 8% of those classified as income poor are not also fuel poor – fuel poverty plays a much larger role in rural poverty than in urban poverty. While there are some differences on average between the housing stock in urban and rural areas (there are few rural dwellings in multiple occupation), by far the biggest driver of this fuel poverty is not being on the gas grid. In urban areas 92 per cent of properties are able to connect to the gas grid but 64% of rural houses do not have that option.
Electricity is cheap to install and familiar to users – but it is very expensive to run and ties household emissions to that of the electricity grid. Some emerging technologies such as infrared have some potential applications (particularly in solid stone-wall dwellings) but are probably not optimal for most housing.
― Household-mounted solar thermal is cheap to install, cheap to generate and highly flexible – but a standard installation will not meet 100 per cent of heating need (particularly in properties which share a roof) and would require the additional installation of heat storage or for changes in occupants’ habits and behaviours. Large-array solar thermal has even more advantages than household-mounted, producing very cheap heating that can be stored and is capable of providing over half of heating requirement – but it requires a district heating system to distribute the heat.
― There are a variety of biogas and waste incineration options including anaerobic digestion of waste and the use of biomass to generate bio LPG. It has the advantage of being an easy, direct replacement for natural gas and oil but government support will be required to incentivise the development of domestic sources of bio LPG supply.
― Both ground-source and air-source heat pumps have a role to play but are site specific, have long repayment times and all require an additional heating source to top up the heat level (which usually involves nonrenewable heating sources). Larger scale heat pumps attached to district heating schemes have much higher efficiency.
― Hydrogen can be used as a direct gas replacement but is very expensive to produce and large-scale deployment would almost certainly rely on carbon capture and storage (CCS) and would compete with other uses for hydrogen such as transport. (However, this is a better option for communities which have excess renewable electricity supplies, such as islands with limited capacity to export to the grid).
― Wood fuel biomass has significant scope to replace existing heat sources at a fairly competitive price, but its use in urban areas will be limited by pollution legislation and it would be imperative to ensure a reliable domestic supply chain for the fuel source. The conclusion from this review of heating options is there will need to be a multiple-technology approach to decarbonising heat everywhere in Scotland with no single credible solution able to meet demand in any one location (and few households having the conditions which would enable a single renewable replacement technology)