Other measures involve switching small businesses off coal-fired boilers and on to the power grid, and converting residential neighbourhoods to gas heat.
Big energy savings have been achieved by seemingly minor technological changes such as moving from gas boilers for space heating to heat pumps.
Solar-thermal power stations, which employ mirrors to concentrate sunlight on boilers and thus raise steam to generate electricity by turning turbines, are far from cheap compared with gas-fired stations.
By 2020, the city will have removed all coal burning boilers and the proportion of clean and high-quality energy will be above 90%.
"It's a transformative change for the country," said Naushad Forbes, president of the Confederation of Indian Industry and co-chairman of Forbes Marshall, which makes boilers and industrial equipment.
" The policy gave free coal for fuel boilers to heat homes and offices to cities north of the Huai River, which divides China into north and south.
