Fuel poverty is forecast to rise and could affect average households from this year, a Scottish Government report has warned.
Figures for 2010 showed there were 658,000 households who were classed as being in fuel poverty - meaning they have to spend more than 10% of their income on energy.
That is down from the previous year's total of 766,000.
But the Fuel Poverty Evidence Review, which looked at the extent of the problem across the country, estimated this would increase by 7% in 2011 to more than 800,000.
It also warned that the proportion of household income spent on fuel would also rise, pushing average households into fuel poverty from 2012.
While the actual figures for fuel poverty in 2011 are not available until later this year, the report stated: "Fuel poverty projections for 2011, based on modelled data, estimate a rise of 7% from 2010 figures.
"It is projected that over 800,000 Scottish households (35%) were fuel poor in 2011."
The report stressed that the data was "still being developed and, at best, should be considered as indicative".
But it added: "If five-year trends in the fuel poverty ratio continue, it is projected that the Scottish mean fuel spend will exceed 10% on average by 2012, steadily rising to 12% by 2015, pushing the average household into fuel poverty from 2012."
Infrastructure and Capital Investment Secretary Alex Neil said: "Scotland is an energy-rich nation and no-one should have to choose between heating and eating. That is why we are continuing to lobby the UK Government to take a firmer stance with energy companies - encouraging them to cut their prices in order to help boost household incomes."