Always the best fuel is the least fuel and this is down to insulation. Enough insulation and you don’t need a central heating system. This is the basis of the PassivhausSee more on the Passivhaus standard. The PassivHaus Institute has pioneered a standard for low energy buildings. It includes very low energy usage and ways of achieving this. The word is derived from the idea of buildings which are fundamentally low energy and passive solar heated rather than using extra gadgets to heat them. See Passivhaus for the UK branch of the organisation. system. With enough insulation the heat naturally generated within a house (lights, cooking, body heat etc.) is enough. When possible go for Passivhaus standard.more +/-»
So if you want a renewable way to heat your home (and stepping aside from the nuclear debate) the choices are -
- solar hot water
- solar PVPhoto Voltaic. referring to the generation of electricity from sunlight
- passive solar including Passivhaus
- biomass including timber
The biomass options available depend to a large extent on how much space you have to store fuel. Logs, bales of straw, wood chips, pellets etc. all require considerable dry storage areas which are not usually available in urban areas. However, in rural situations they may be a very practical choice. This brings up two further questions to do with whether these fuels can be made to burn cleanly and how sustainable they are as a fuel source.
Well there’s coal (do you remember coal?) and there’s gas and there’s oil – all ways that Gaia sequestered carbon under the ground in order to stabilize world temperatures.
The best of these to burn in your boiler is natural gas because it is partly hydrogen and so produces relatively less CO2Carbon dioxide is a gas which is given off when carbon based materials such as fossil fuels (coal, oil, and natural gas) are burned. It is called a greenhouse gas because it works like the glazing of a greenhouse and causes global warming. The idea of burning coal or oil is in some ways bizarre when you consider how polluting they are and how useful they are for making plastics, chemicals etc. In future years this practice may be looked back upon with amazement.
The problem with electricity
Although, on the face of it, the idea of simply signing up with a supplier of renewable electricity for heating seems like a good one there is a major flaw in this approach. (We are talking here about electrical resistance heating rather than electrically powered heat pumps). This is because the long term demand for electricity is very high and it is generally very inefficient to generate it in the UK. It is better to save what electricity there is for uses which can only be fulfilled by electricity (such as lighting, telecoms etc). The argument is powerfully put by David Olivier and Cath Hassell here
The relative costs and attributes of domestic fuels can be found on Nottingham Energy Partnership’s ENERGY COST COMPARISON web site. It includes their CO2 emissions taking into account the efficiencies of the fuel’s boiler.
Energy sources can generally fall into two types: renewables and non-renewables. Where you decide to put nuclear energy is a bit of crystal ball gazing because whereas nuclear fission is looking quite limited due to the amount of high quality uranium ore available, nuclear fusion may, just, by the skin of its teeth, come to the rescue in time. Then we would all have limitless safe energy. Don’t hold your breath.
The two problems with nuclear fission are that accidents can be catastrophic, and no-one has yet found a secure way of dealing with the waste products, except possibly the Finns. See for instance the recent National Audit Office report on the appalling state of Sellafield. (There is also the insidious link between nuclear power generation and nuclear weapons – though it can be argued that this is more a matter of politics than technology)Powered by Hackadelic Sliding Notes 1.6.5