A global energy leader says the United Nations' hope of having universal access to power by 2030 is far too optimistic and won't even be achieved by 2050.
The World Energy Council represents hundreds of global energy companies and interests and its secretary general, Christoph Frei is in Auckland for the New Zealand energy sector's annual forum.
The UN says about four billion people do not have access to modern power sources but it wants that reversed by 2030.
Mr Frei said even by 2050, there are still likely to be up to 500 million people without modern power - many of them in sub-saharan Africa.
He said most of those people will be living in extremely remote rural communities and new, unconventional solutions will be needed to bring them access.