The news that global carbon emissions reached their highest ever level in 2010 can have surprised few people.

Against that backdrop, reducing the amount of energy consumed by households in industrialised countries is a key battleground for tackling carbon emissions. Increasingly, the British government seems to be catching on. Few streets have no provision for recycling, and the "green deal" aims to insulate millions of homes – reducing carbon emissions and (ultimately) saving householders money.

But a newly published paper in the journal Energy Policy shows that even straightforward carbon-saving activities such as home insulation are not always quite what they seem. The problem is that making one change around the house leaves the door open for other changes – which might include "rebound effects" that undermine the carbon savings. If a driver who replaces their car with a fuel-efficient model takes advantage of the cheaper running costs and drives further and more often, then the amount of carbon saved is clearly reduced.

Even worse, there are some circumstances where seemingly carbon-saving measures actually increase overall emissions – where the change backfires completely. Dr Angela Druckman and her colleagues analysed several different types of patterns of hypothetical household behaviour. Using the basic assumption that the money saved on reducing energy consumption has to be spent on something, they examined several different carbon-saving behaviours, and asked what happens next.