Go to Emilis' home page

Wood lot

Effective heating fuels

Effective heating fuels should contain high calorific value in operation.
While it is possible to heat (and cool) by conversion, notably with reverse cycle processes, this approach uses large quantities of fuel (electricity) with a low calorific value. The process also shifts the heat from the colder environment toward the environment being warmed. In effect the technology is moving the heat opposite to the direction of natural flow. A continuous heat import is required to maintain comfort.

Environmental issues

Where the electricity is generated by fossil fuels, there are environmental impacts on a large scale; and there are local environment impacts of the reverse cycle process. This is most noticeable where the reverse cycle system is in cooling mode, and expelling heat to the already hot external atmosphere. .
The difficulty in superheating that air outside the building is noticeable by the machinery struggling to cope with the cooling demand..

Low energy development

The advantages of introducing heating where required in a low energy demand building include that:-
  • only modest amounts of heating are required to supplement the building's solar gain, the thermal storage and envelope insulation retention of warmth
  • the supplementary heating can cease once initial comfort is achieved
  • the initial heating can be circulated around the whole space by ceiling fans, and the retained heat in thermal mass elements balances the warming.

Various gas fuels

Gas fuels often have the same limitations as electricity. .
Where gas is captured from fossil fuel sources (natural gas deposits, extraction from coal and coke), and the complex hydro-carbons created burn to produce a range of pollutants..
However, gas has development potential with simpler hydro-carbons, notably methane, available from land fill and sewerage processing, where burning creates simple gas pollutants capable of absorbtion into the environment..
Further evolution of the gas industry includes hydrogen, generated by electrolysis, where combustion generates principally water as the waste product.

In contrast, electricity is difficult to generate by renewables to quantities and rates that are drawn by reverse cycle systems..

Inappropriate use of wood fuel

Wood fuel is associated from the beginnings of industrialisation with smog and air pollution. Wood fuel for heating may be inappropriate in locations where airborne pollutants do not disperse, notably in air trapped by terrain or inversion layers in the atmosphere, despite improvements in combustion technology..
Wood fuel is also inappropriate where the fuel source is not compensatable at point of use.

The most applicable wood fuel uses therefore can be space and cooking heating on sites where wood lot re-growth matches wood fuel use; thereby mitigating both environmental land impact and air pollution/mitigation cycles.

This architectrual practice has used wood heating including wetback boost to water heating systems in locations of detached buildings on land revegetation projects where bushfire protection maintenance, vegetation die-back detritus, and wood lot harvesting are matched with ornamental, erosion protection and wood lot re-growth planting by the occupiers.

End of section