Do climate worriers use more electricity?

Carbon Brief

The UK's Telegraph and the Mail say people concerned about climate change use more electricity than those who think the issue is too distant to worry about, according to new research.

The Telegraph quotes Conservative MP Peter Lilley:

"The survey exposes the hypocrisy of many who claim to be 'green': the greater the concern people express about global warming the less they do to reduce their energy usage."

But Lilley's strong conclusions are not supported by the study in question, which comes with some significant caveats. The researchers themselves say there's no significant effect of people's beliefs:

"None of the stated attitudes about environmental or climate change had any significant impact on overall energy use when household age was taken into account."

Let's take a look at what the study says, and what it doesn't.

Small survey

The articles are based on a survey and detailed study of the electricity use of 250 homeowners in England during 2010-11. The work was done for the department of energy and climate change (DECC).

The survey measured the electricity consumption of the households in some detail, monitoring use by TVs, lighting and so on. This is expensive, which is why the survey was small.

The study also asked one member of each household to answer questions about their energy use and their environmental beliefs. One question asked if they agreed or disagreed with the statement: "The effects of climate change are too far in the future to really worry me."

Age effects

The researchers plotted responses to this question against average energy use. Respondents that "strongly agree" that climate change is too far in the future to worry about also had the lowest electricity use, as this chart shows.

Source:  Savings, belief and demographic change, report for DECC, graph by Carbon Brief

But the researchers said most of this correlation was down to age effects. It turns out that pensioners tend to be more careful with electricity use, and they are also less likely to be worried by climate change.

If you remove the pensioners from the analysis, only a weak correlation between climate concern and energy use remains, the researchers say.

It's also worth remembering that this is a now a sub-set of an already small sample. There were only five households falling into the 'low electricity-using and unconcerned about climate change' group, for instance.

The study says:

"Ideally there would have been thousands or perhaps tens of thousands participating in the study… the small sample makes it impossible to extrapolate reliably to all homes, but it is a starting point."

So we can't make any reliable statements about English households in general, based on this small survey alone. Nicola Terry, one of the study authors tells Carbon Brief:

"It is unfortunate that [the newspaper articles] have reported a link between climate concern and electricity use as fact whereas in practice the trend was probably not significant."

Correlation is not causation

Another significant caveat noted by the study is that correlation is not the same as causation. It says "it is very seldom possible to infer unambiguous causality from the correlation". Height correlates with reading ability, but that isn't because being tall makes you better at reading -- it's because children are short.

Might the apparent link between concern over climate change and electricity use be better explained by other factors?

The study looked at the factors with the largest influence on household electricity use in the survey. Socio-economic status, work status, the number of people in the household and its floor area were the top determinants of electricity use, they found.

Above-average users include households of socio-economic grade 'A', households that are large in area or number of people, and those who are not working, as the chart below shows.

Below-average users include retired households and small households. Households that say they're not worried about climate change feature too -- but remember there were only five of those out of a total of 250.

Source: Savings, belief and demographic change, report for DECC, graph by Carbon Brief

In general the study found little correlation between environmental beliefs and electricity use. It notes separate research covering 24 countries that found countries where environmental concern was high tended to have lower carbon emissions.

The same work found environmental concern translates into certain activities at a personal level, like recycling, but not into energy saving behaviour. Terry says:

"Being concerned about climate change does not necessarily mean you feel motivated and able to do something about it… A sizeable minority in our survey agreed with the statement 'Its not worth me doing things to help the environment if others don't do the same', for instance."

So it might be fair to say, as the Telegraph do in another piece, that we humans are all mouth and no trousers. On the basis of this English home survey, however, we can't really tell.

Originally published on Carbon Brief. Reproduced with permission.