fuel sources

Fuels used to cook barbecue food include charcoal (lumpwood[1] and briquette[2]), wood, Liquid Petroleum Gas (LPG) and the less prevalent pellet cookers that use wood pellets and electricity. Each fuel has its own sustainability considerations, LPG is a non-renewable fossil fuel and wood from less well-regulated areas can lead to deforestation[3] and biodiversity loss (Njenga et al., 2013, p.360). The focus for this study is lumpwood charcoal as it is the fuel most unique to barbecue and despite it potentially being a renewable energy source, it is fraught with sustainability issues.

Charcoal is formed from the carbonisation of biomass, primarily wood, where it chemically decomposes rather than burning to ash in an open fire (FAO, 1983). During thermal decomposition GHGs and other harmful gasses are produced such as methane, carbon dioxide, carbon monoxide, Volatile Organic Compounds (VOCs) and non-methane hyrdrocarbons (Antal and Grønli, 2003, p.1621 and Adam, 2009, p.1924). Increasing the length and temperature of the process (in excess of 500°C) leads to more emissions but leaves a higher fixed carbon content in the charcoal, making it a more efficient fuel (Kabir et al. 2010, p.498).

The environmental impact of charcoal production can be significantly reduced by using sustainably managed forestry and efficient equipment such as a ‘retort kiln’ that burns off the harmful gases (reducing air pollution by 75%) and uses the heat generated to fuel the kiln, reducing overall energy input (Adam, 2009, p.1923). In the UK 80% of charcoal is imported from developing countries such as Kenya, where over 75% of charcoal production is deemed unsustainable and 13% is produced illegally, usually in earth kilns that release harmful emissions into the atmosphere (Johnson, 2009, p.371, Njenga et al., 2013, p.363 and Adam, 2009, p.1923).

In addition to the environmental impact, economic and social sustainability aspects of sustainability also feature. Charcoal production is an important livelihood in some poor, rural communities, for example Kenya where charcoal is the fourth largest source of GDP and supports two million people,[4] and Tanzania where revenue generates five times the revenue of coffee and tea combined (Neufeldt et al., 2015, p.2). On social aspects of sustainability, good examples include empowering marginalised sectors of society in charcoal producing communities (Njenga et al., 2014, p.360). This, however, contrasts with other areas where women are marginalised, producers are disempowered, officials use the trade as a source of bribes which fuels corruption and inequality, and agricultural male labourers are misemployed from primary employment (Neufeldt et al., 2015, p.5). This is before one considers that illegal charcoal production in Somalia funds the militant Islamist group, al-Shabaab, that resulted in a UN ban on exports of Somali charcoal (Rembold et al., 2013 and Oduori et al., 2011).

In most cases charcoal is having a negative impact on the environment and mixed impacts on social and economic aspects of sustainability. However, the World Agroforestry Centre[5] states that “Charcoal is more often seen as a problem rather than being part of a solution to addressing energy-related and economic challenges facing developing countries”, and that “if managed properly charcoal can provide a low-cost and locally available energy source that has the potential to become sustainable and contribute significantly to poverty alleviation” (Neufeldt et al., 2015, p.v and p.10). The implication for the UK barbecue food industry, where charcoal is a key component, is that there are really sustainable and really unsustainable methods of producing charcoal.

[1] Charcoal that resembles the wood is was made from.

[2] Pillow shaped, press formed lumps of charcoal with binders and other materials added.

[3] Up to 12.98% in some areas of Somali forest areas in five years (Odouri et al., 2011, p.1178)

[4] The incomes streams in Kenya above charcoal include tourism, horticulture and tea, the latter of which charcoal is almost on a par with (Njenga et al., 2013, p.361).

[5] A science-based non-profit research organisation.