Tower Power Kenya Ltd plans to invest $38 million in two biomass electricity generating plants with a combined capacity of 23 MW.
The facilities are to be constructed at Kalalani and Ngambo in Kinango and Marigat districts respectively in the rift valley.

The invasive Prosopis Juliflora tree will be used as raw material for heating water to produce steam to drive the turbines to generate power.

According Etcon EA Ltd, an environmental consultancy firm, construction work on the Marigat facility is expected to start in July, subject to approval from the National Environment Management Authority.

“Prosopis Juliflora has successfully been used as feedstock at energy generation plants in India; we hope to achieve similar success locally,” said Joseph Kiragu in an environmental impact assessment report prepared by Etcon for Tower Power.

The report also notes that the entire 11.5 MW to be generated at Marigat will be injected to the national grid at a price agreed on with Kenya Power.

The 11.5 MW of electricity to be generated at Mariakani will first be used to meet internal needs of Mabati Rolling Mills and Kaluworks Ltd, owned by Comcraft Group. The surplus will be sold to Kenya Power.

“If this plant is rolled out successfully, it will attract industrialists to Mariakani and help to decongest Mombasa as well as open up the unproductive hitherto coastal parts,” said Mr Kiragu.

He said the use of the noxious Prosopis juliflora for power generation, will help to generate income for local communities that grow it, and help to tame it.
The initial biomass required for the Mariakani plant will be secured from Bura, Hola, Garissa, Taveta and Tana.

The areas have abundant Prosopis juliflora trees which were planted on large scale to stop desertification.

Prosopis Juliflora is a hardy plant that grows very fast even with little water and is ready for harvest within two to three years.
The harvested plant grows back to its original size in 16 to 18 months.

The first documented introduction of Prosopis juliflora to Kenya was in 1973, and was used for rehabilitation of quarries in Mombasa by Bamburi Cement, with seed sourced from Brazil and Hawaii.