Ghana needs 340 megawatts (MW) of reserve power capacity for contingencies such as the recent shutdown -- due to a cut-off of natural gas supply -- of the 200 MW Asogli Power Plant which has caused electricity to be rationed to homes countrywide.
That is the “ideal scenario” for a country that consumes about 1,700 MW of power currently, boss of the Ghana Grid Company Limited (GRIDCo) Charles Darku, told the B&FT during a briefing in Accra on the current power-supply emergency.
“Electricity demand has peaked at 1,700 megawatts, so we need a reserve of at least 170 MW and an additional reserve -- if a machine goes out and you need to bring it back on -- of 170 MW. So we really should have a reserve of around 300 MW; but we don’t have it,” he said.
“We have eaten into the existing reserve margin because the load growth has exceeded generation. It’s a race between the demand and the growth and balance of the load,” he added.
Mr. Darku said electricity demand and consumption hit 1,664 MW in 2011 and has grown to 1,725 MW in 2012 with the potential to peak at 1,800 MW by the end of the year. On average, electricity demand is expanding at between 8-10% every year.
Securing sufficient, cost-effective supply of electricity in the medium-term hinges on gas fuel expected to come onstream after the pipeline project carrying natural gas from the Jubilee oil field to onshore sites is completed, said Maxwell Odoom, a Deputy Chief Executive of the Volta River Authority (VRA) at the briefing.
The West African Gas Pipeline Company (WAPCo), which operates the pipeline that delivers natural gas to Asogli and plants run by the VRA, has announced a total cut-off of gas supply to its onshore stations in Tema and Takoradi due to damage caused to a portion of the pipe in the Lomé seas by the anchor of a ship.
While the VRA’s plants have been reconfigured to run on crude oil, Asogli, which is fired by gas only, has completely shut down. Coupled with the shutdown of a 110 MW plant in Takoradi that is undergoing repairs, some 310 MW of installed power capacity is presently unavailable.
The Takoradi plant is however expected to resume production before the end of September, according to senior VRA officials.
Mr. Odoom put the cost of running the VRA’s thermal plants on crude oil at US$40-45million monthly, saying this is a more expensive alternative compared to natural gas.
The effect of this on tariffs will depend on the outcome of consultations with the Public Utilities Regulatory Commission (PURC), he said.
William Hutton-Mensah, acting Managing Director of the Electricity Company of Ghana (ECG), said businesses will not be affected by the power-rationing exercise because the utilities want to save them production-cost increases and output cuts.
“We’re giving the topmost priority to industries. There will be minimal effect on them in terms of electricity supply,” he said.