1 July 2013 — Targeting energy efficiency and conservation in a small number of households could have a big impact, according to a study which found that a fifth of households are responsible for 50 per cent of carbon emissions.

The study published in Environmental Science and Technology measured differences in energy demand at the household level using a life cycle assessment of household consumption. It found that of more than 3000 Swiss households studied, 21 per cent accounted for almost 50 per cent of greenhouse gas emissions.

The key factors in a small proportion of households having disproportionate carbon footprints were the demands of large living spaces – meaning extra energy for heating, cooling and lighting – and long car commutes.

The study authors said that targeting this small number of households could have huge greenhouse gas reduction potential.

“If their emissions could be halved, the total emissions of the community would be reduced by 25 per cent,” they said.

The study authors reported that 72 per cent of greenhouse gas emissions were directly or indirectly attributable to household consumption, but that policymakers had been focusing on supply-side issues like energy source to the detriment of the demand side.

“For a serious debate about greenhouse gas emission reduction policies, it is crucial to analyse household consumption patterns, that is, to quantify the individual demands and environmentally assess their supply,” they said.