Tanzania has extended nationwide power rationing after a prolonged drought led to a 230 megawatt (MW) deficit on the national grid, a senior official said on Tuesday.

Energy and Minerals Minister William Ngeleja told parliament the state-run power utility, Tanzania Electric Supply Company (TANESCO), was generating just two thirds of the nation's total energy demand.

Only 470 megawatts of electricity is currently being produced, which is equivalent to 67 per of the total energy demand in the country, he said.

The minister said peak demand stands at 833 MW. Some lawmakers described the shortfall as a national crisis for east Africa's second largest economy.

TANESCO imposed power cuts in December after a shortage of natural gas supply to turbines led to a 40 megawatt deficit on the national grid.

Power rationing was expected to end in January, but drought at hydropower stations has now pushed up the power deficit to 230 MW.

Most of Tanzania's electricity is hydropower generated. Failed rains have cut output at the dams to 180 MW, with another 280 MW being produced by gas and diesel-fired turbines.

We anticipate having an average shortfall of 264 MW of electricity from the national grid this year because of expected long spells of drought, he said, adding there would still be a deficit of 67 MW even if the next rains fell.

Ngeleja said the government was considering inviting independent power producers to set up emergency power-plants that could generate an additional 260 MW of power.

Tanzania plans to produce up to 1,000 MW from new coal-fired power plants over the next five years. Only 14 percent of Tanzania's 40 million people are hooked to the grid, while demand is growing by 10 to 15 percent annually.

More than a fifth of Tanzania's generated electricity is lost during transmission and distribution, but the government aims to reduce this to 15 percent, Ngeleja said.