More than one billion people worldwide inhabit a modern dark age, with a lack of electricity and modern cooking facilities condemning them to deep poverty, the top UN energy body said on Tuesday.

According to the International Energy Agency, more than 20 per cent of the global population, or 1.4 billion people, lack access to electricity, while about 40 per cent rely on the likes of wood stoves for cooking.

"This is shameful and unacceptable," the IEA said in a report released at UN headquarters in New York during a summit on world poverty.

The ability to flick on a light switch, something taken for granted in the developed world, is utterly out of reach in many countries - and so are all the economic advantages that come with modern power.

For example, New York state's 19.5 million people consume as much residential electricity as all the 791 million inhabitants of sub-Saharan Africa, excluding more developed South Africa.