Farmed Firewood – an important resource in a sustainable future.

Recently there has been some discussion in social media posts surrounding wood fires, smoke generated and an inference that they are using fossil fuels.

We would like to share some of our knowledge around sustainable fuel sources for home heating, and controlling the nuisance smoke from fires.

First up lets deal with the issue of fossil fuel. Firewood is NOT fossil fuel, nor does it share any characteristics with fossil fuels, other than perhaps you burn it. Fossil fuels are by definition fuels derived from plants that lived in prehistoric times, that geological forces have buried and compressed forming gas, oil and coal. The environmental issue with using fossil fuels is that you are releasing carbon back into the atmosphere that has been trapped and removed from the environment for tens or hundreds of thousands of years. This affects the balance of CO2 in the atmosphere badly.

Firewood does not do this, particularly if it is farmed wood or if it is harvested from native forests in a sustainable way. There IS a carbon cycle when using firewood but its not long term and it is closed loop. The carbon you release by using our firewood today has been captured from the atmosphere in the last 20 years and will be recaptured as replacement trees are planted over the same kind of period.

From an ecological point of view farmed firewood and all similar wood products have ecological credentials right up there with wind and solar power.

As for the issue of nuisance smoke – burning firewood can and should be clean and efficient, modern fireplaces have clever designs with multi stage combustion and high efficiency ratings. So what causes smoking ? –

1) The number one cause of smoking is poor feed stock. Most of our customers are very aware about buying green wood – unseasoned wood burns slowly at low temperatures and generates a lot of smoke and tars. There’s another factor here thats often overlooked and has much the same result – damp wood – stored in the rain or on damp ground even seasoned firewood burns very poorly. Store your wood out of the weather AND ask your supplier if they can deliver DRY, seasoned wood if you intend to use it within a few weeks of delivery. Rain soaked deliveries are a problem.

2) Oversized fireplaces. Lots of customers we visit have very large fireplaces. The issue with this is if you run your fire for long periods you eventually have to damp it right down by suppressing the incoming air so it does not overheat your house. This has much the same effect as green wood – a fire left with little airflow for long periods ends up burning at low temperatures and producing a lot of poorly combusted by products.

If you feel the cold and want to run your fire for long periods, consider a smaller fire, you can run it at levels closer to its rated output, in its efficient zone of operation achieving smoke free combustion. The only disadvantage is it might take a few hours to initially heat the house, the big advantage is better efficiency means more heat for less wood AND very little smoke.

3) Poor maintenance – modern wood fires rely on complex air paths to heat the incoming air and subject the outbound air to a high temperature second combustion in a chamber above the fire. Its really important for their efficiency to make sure the chimney is clean AND that all the steel plates and ceramic or fibre cement bricks are in good condition. Over time the steel absorbs a lot of carbon from the combustion and becomes brittle and cracks allowing the air flow to take shortcuts and incomplete combustion results.