Thermogram of house showing heat loss and energy inefficiency
A conservation charity has called on the Scottish government to "rethink" its plans to eliminate fuel poverty.
WWF Scotland wants ministers to drop their "means tested" approach to cutting fuel poverty in favour of street-by-street home refurbishments.
It believes measures to cut consumption in every home would improve energy efficiency and lower heating bills.
Figures published last week showed that there are now 600,000 families living in fuel poverty in Scotland.
The government's Energy Assistance Package replaced the Central Heating and Warm Deal package last year.
It is designed to help reduce fuel bills and improve the energy efficiency of homes, by using benefits and tax credit checks to identify those most at risk of fuel poverty.
It also provides a package of standard insulation measures, such as cavity wall and loft insulation to older households and those on benefits.
But the charity said a study conducted with the Energy Agency showed that a non means tested approach was "highly successful" in reducing the cost of energy, as well as lowering the country's carbon emissions.
Under the Scottish Climate Change Act, the Scottish government has pledged to achieve a 42% cut in carbon emissions by 2020.
The "Achieving Our Potential" report analysed three schemes in Girvan and Hadyard Hill in South Ayrshire and Fintry in Stirlingshire, where a blanket approach to improving home energy efficiency had been trialled.
Free insulation was given to 1,584 homes in Scotland during the trial scheme.
The average annual energy bill fell by between £180 and £600 after the insulation measures were installed, and in Girvan, annual disposable income increased by £560,000 across the community.
The charity said fuel poverty could be reduced by up to 26%, and produce an average cut in carbon emissions of 19%.
Elizabeth Leighton, senior policy officer at WWF Scotland, said: "If the Scottish government is to meet is own target of eradicating fuel poverty by 2016, we believe it is needs to rethink its current "means testing" approach.
"While there are many positive aspects to the government's fuel poverty package, this report clearly shows an area-based scheme, available to everyone, delivers a triple benefit by reducing fuel poverty rates, carbon emissions and energy costs."