Home Q&A: What's the most sustainable real-flame heating for outdoors?

Rio automatic gas fire, €899, Bioheat Ireland. Gas will deliver more warmth than a fire pit or chiminea.

Question

What is the most sustainable real-flame heating for outdoors?

Answer

When you burn anything outside, including timber, it produces carbon dioxide, and therefore it has a carbon footprint. Combusting wood or charcoal, we’re producing some particulate debris and poly-cyclic aromatic hydrocarbons too, much of it too small to be seen. 

Bioethanol is often hailed as more eco-friendly than gas or wood, but it, too, has an impact. The fluid is derived from renewable resources, and it burns cleaner than other fossil fuels, producing a minute amount of CO2 and some water vapour. 

That said, it provides very little heat in a light breeze outdoors, so consider it as a decorative feature with a flickering real flame. 

When using bioethanol fires, keep an eye on ventilation if you’re undercover or in the conservatory/garden room. The National Energy Foundation UK advises: “If water vapour meets cold surfaces (such as single-glazed windows and uninsulated walls), condensation forms, bringing with it the risk of mould formation.” See nef.org.uk. 

Gas will deliver more warmth than a fire pit or chiminea and in a fire table (which is relatively energy efficient) burns cleaner than timber, and can be trimmed automatically using either LPG or natural gas. Together with the carbon footprint, 40% of the heat provided by real-flame gas, even trained down with a cowl or hood, will be lost to the air.

Living in the suburbs? Your best bet in environmental terms is infrared, electric heating outdoors and/or a geansaí.

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