Sustainable firewood We test the nine best options... and please let’s leave kameeldoring alone
Given the masses of invasive trees in South Africa and the thousands of jobs involved in clearing them, beating the cold with a wood fire makes sense. Botanist Donovan Kirkwood tested nine wood types to find a long-burning, environmentally friendly choic
Ionce tried internet dating and mostly discovered that everyone loves drinking red wine in front of a wood fire. I’ve lived with wood fires all my life, from old-fashioned open fireplaces while growing up to the modern glassfronted cast-iron stove that now sits in the lounge and keeps our rather draughty house tolerable in winter. Because I’m a botanist, the dancing flames are made even more magical by the idea that I am literally watching sunlight trapped by trees over the years being set free.
In South Africa, many factors also make heating with wood a more sustainable choice. We have invasive exotic trees infesting more than 10 million hectares of land. Even changes in indigenous ecosystems are a problem, with southern Africa’s iconic open savannahs experiencing serious bush encroachment and conversion to impenetrable thicket. Furthermore, harvesting of firewood supports clearing and creates thousands of jobs. Wood is fundamentally a renewable resource, made almost entirely from atmospheric carbon dioxide and sunlight by plants, so carbon dioxide released by burning sustainably harvested or invasive alien trees is not usually considered to contribute to increased atmospheric carbon dioxide or global warming. >
The alternatives for heating in South Africa aren’t great. We don’t have cleanburning domestic piped gas. Electricity, the most accessible and convenient alternative to wood heating, comes from a national grid that has barely converted to renewables. Despite our generally modest living standards, South Africans already contribute double the average global carbon emissions per person according to the CSIR. Nearly all of our electricity, 90%, comes from burning fossil fuels – a terrifying 90 million tonnes of dirty, low-quality coal a year, burned in power stations with inadequate emissions control.
Wood heating is sometimes presented as the ultimate low-tech green solution. Of course, nothing is quite so simple. There are challenging realities to consider. Cleaning out wood ash and stoves is not for everyone. Inefficient, smoky fires aren’t romantic at all. There are health risks, and environmental issues can be confusing, with most of the online advice coming from other countries. So what do you need to know about wood fires and firewood?
First, the health risks of heating with wood are real, confirmed by a plethora of studies, and one needs to understand some basics to avoid them. A little wood smoke smells lovely and is natural, but it does contains many toxic chemicals with scary names and scarier health effects – benzene, formaldehyde, acrolein and polycyclic aromatic hydrocarbons (PAHs). Fine airborne particulates with a diameter less than 2.5 micrometers (PM2.5) are known to be particularly damaging. Australian research has shown that even the >