Botswana will award a contract to build a 300 megawatt (MW) coal-fired power station this week that could transform the southern African nation to be an exporter of electricity by 2018, the mining and energy minister said on Monday.

“Hopefully the decision will be made by Thursday,” Mining, energy and water minister Kitso Mokaila told a diamond conference in Gaborone, adding that construction on the Morupule plant could start next year.

Botswana, which is facing both electricity and water shortages, slashed its 2015 growth forecasts by almost half to 2.6 percent in September due mainly to a drop in diamond prices. Botswana is the world’s top producer of diamonds by value.

The Morupule plant, which is expected to take three years to build, will lift power generation to more than 1,000 MW, well above a national demand of about 610 MW, said Mokaila.

Mokaila said Botswana will start drawing water from the nearby Lesotho as a regional drought worsens and hit water levels at its main water reservoir – the Gaborone dam.

The land-locked Lesotho, a mountainous country completely encircled by South Africa, supplies piped water to its much bigger neighbour. Mokaila said Botswana had negotiated to be part of the water supply from Lesotho.