Nigeria's power minister wooed prospective investors in 10 new power plants on Tuesday, promising them multi-billion dollar profits akin to those achieved by the telecoms sector since it was privatised in 1999.

The government opened a roadshow on Monday to try to attract investors to buy the majority stake in new gas-fired plants, which it said would have a combined capacity of 5,453 megawatts (MW), enough to almost double the power supply.

Nigeria's government is offering to sell 80% of each plant, while keeping 20% under state ownership. It wants to complete the deal on all 10 by mid-2014, but investors are wary of huge risks such as gas supply and transmission problems.

"We have a unique opportunity here ... it is being given to investors on a platter of gold," Power Minister Chinedu Nebo told the audience in a glitzy hotel in Lagos, the main commercial hub in Africa's second biggest economy.

"What happened in the telecoms industry is about to repeat itself in the power sector, except we are expecting even greater results ... it will dwarf what happened in telecoms," he said.

The deregulation of telecoms paved the way for private mobile phone operators to set up shop and reap huge profits. Largest operator MTN makes around $2.5 billion annually in Nigeria, its biggest earner.

And the owner of No. 2 operator Globacom, Mike Adenuga, is Africa's fifth richest man, with a $4.7 billion fortune, according to Forbes.

Yet unlike in telecoms, attracting investors worried about risks such as the reliability of gas, the distribution of what they produce and ensuring payment could still prove tough. The power sector has been a mess for decades and there remain huge hurdles such as disruptive unions and powerful interests like the generator and fuel importers who profit from the status quo.

The sale of the plants marks phase two of President Goodluck Jonathan's plan to end the crippling power shortages that have hobbled industry and made daily life a misery for tens of millions of Nigerians. If he succeeds, it would seal his legacy.

Despite being the continent's top oil producer and holding the world's ninth largest gas reserves, power output is a tenth of South Africa's for a population triple the size. Sorting it out would cut business costs by a third, economists say.

"It will revolutionise the economic situation in Nigeria, reduce poverty, create jobs," Nebo said.

In the first phase, underway since last year, the state power firm is being broken up and sold for a total of around $2.5 billion. This next phase invites investors to buy new assets, instead of decrepit old state ones.

This in some ways is a bigger risk for investors because the initial capital investment could be up to $500 million, more than five times the going price of the state assets, said a government source close to the deals.

Nigeria has so far spent $15-$20 billion on the plants, so even at this price tag, it stands to lose a lot of money.

Arif Mohiuddin, a consultant working on the deals, said the government would compensate power plant owners for any income lost due to a lack of gas supply or problems transmitting electricity through the grid to end users.

"They (the investors) only take risks in terms of the operation they are running, not for instance the gas supply," Mohiuddin said.