Clean energy schemes are not doing nearly enough to ward off climate change, the International Energy Agency says.
The 29-member Paris-based agency, to which New Zealand belongs, said progess in clean energy was falling well short of what was needed to limit global temperature rises to no more than 2 degrees Centigrade by 2050.
That is the level agreed by political leaders internationally to limit the effects of climate change on the environment.
But the International Energy Agency said the energy sector was falling well short of what was needed to achieve that.
Executive Director Maria van der Hoeven said the world economy was improving on carbon intensity - that is it is growing its economy faster than its use of energy.
But she said the rate of improvement needed to more than double, from 1.1 percent annually to 2.6 percent.
Ms van der Hoeven also took a swipe at the environmental costs of cooling buildings in summer and heating them in winter.
She said that accounted for 40 percent of final energy consumption - ahead of transportation at 27 percent, and was 70 percent dependent on fossil fuels.
Ms van der Hoeven said sustained effort could reduce that to 50 percent by 2050.
And she said the low cost of fossil fuels at present were an opportunity that should be grasped.
While Brent Crude has rallied slightly in the past few weeks, it is still well under half what it was last year.
Ms van der Hoeven said these low prices could be used as a buffer which would make make carbon pricing and phased-out fuel subsidies more palatable.
The information comes as the World Coal Association reports 40 percent of the world's electricity comes from burning coal, which yields high levels of carbon dioxide.
New Zealand burns comparatively small amounts of coal for its electricity, 79 percent of which is renewable.
Recent data also indicated New Zealand's economic growth was almost twice as high as its growth in electricity consumption.
Its energy intensity is also improving, but at approximately 1.2 percent a year, it is closer to the current world average than the IEA's desired figure.