KenGen seeks more power from steam

The Kenya Electricity Generating Company is seeking consultants to advise it on how to utilise the hot water produced in the Olkaria geothermal wells for additional power generation.
In a newspaper advertisement last week, KenGen said the wells produce about 1,000 tonnes of water per hour.

However, it flows into open drains as the company lacks the necessary technology to produce secondary steam to generate electricity, thereby denying it an opportunity to boost its power output from the Olkaria-based geothermal field.

“The hot brine is currently re-injected or disposed into open drains, thus under-utilising the available energy. The enormous heat contained in the brine can be extracted for additional power generation. It is in view of the above that KenGen wishes to engage a consultant to carry out a study of the brine production and advise on the additional power generation possible from the brine,” read the advertisement.

Hot water, known as brine in industry jargon, is a by-product of geothermal power production as it is generated alongside steam that is used to turn turbines to produce electricity. In other parts of the world where the necessary technology exists, the hot water is run through pipes and used to heat another liquid of a lesser boiling point to produce secondary steam that is used for power generation, a process called binary technology.

The consultant will prepare economic and financial analysis of the proposed binary plants and advise KenGen on the eventual disposal of the water after utilisation at the plants.

Currently, KenGen generates 247 megawatts of electricity at its Olkaria geothermal field. The Olkaria I power plant has the largest capacity, comprising three machines with capacities of 45 megawatts each.

The Olkaria II power plant comprises three machines with capacities of 35 megawatts each. The company also operates two other smaller plants with a collective capacity of seven megawatts.

Last year, President Kibaki presided over the ground-breaking ceremony to launch the construction of a 280 megawatt geothermal power plant, the largest project that the company is undertaking and which is set for completion next year.

Stabilise electricity supply

Once completed, the power plant will add to the total installed geothermal power capacity, boosting efforts by the Ministry of Energy to shift reliance on renewable energy sources as it seeks to stabilise local electricity supply.

Currently, most of the power generated is produced from water resources which fail during dry spells, forcing generators to turn to diesel-driven thermal generation which is prone to price fluctuations in the international oil market, eventually impacting negatively on the overall cost of power.

With the diversification in the electricity production platforms, KenGen stock has gained favourable ground at the Nairobi Securities Exchange, with analysts predicting high returns for investors.