Hydropower generation up 145MW

May 09, 2007

HYDROPOWER generation at the Kiira and Nalubaale power stations in Owen Falls Dam has risen to 145MW from the previous 120MW.

By Ibrahim Kasita

HYDROPOWER generation at the Kiira and Nalubaale power stations in Owen Falls Dam has risen to 145MW from the previous 120MW.

Energy experts said this was due to the rise in Lake Victoria water levels. This is expected to relieve to the current electricity shortage.

The Jinja Pier Gauge data showed that the water levels increased to 11.23m from 10.48m last October.

The stations have a capacity of 380MW.
However, this is dependant on the availability of enough water to turn all the turbines.
Experts are optimistic that once the lake levels hit above the 11.55m mark, more electricity will be generated.

The Lake Victoria outflow is controlled at the Owen Falls Dam by the Directorate of Water Development to mitigate over-drainage of the lake.

To generate the 145MW, operators at the power complex discharge about 908 cubic metres per second slightly above the agreed curve policy.

The policy is the natural water flow that was adopted in the 1950’s before the Owen Falls Dam was built.

The stringent outflow measures follow sharp decline in the lake levels due to prolonged drought, evaporation and excessive water release for power generation in Jinja.

The first reduction was witnessed in February 2006 when the flow was reduced from about 963 cubic metres per second to 850.

A further reduction occurred in August 2006 when the flow was reduced to 750 cubic metres per second.

However, it has been observed that the reduction of water outflow is not accompanied by the corresponding gains in the water inflow.

The lake levels continued to lower up to 10.48m before the trends were reversed with the recent rains.

The agreed curve is a good outflow management tool in Lake Victoria but it requires environmental accounting systems that attach economic values to water ecosystems like forests and wetlands.

A drastic move to the agreed curve without considering environmental management will plunge the power sector and economy into a worse situation. The agreed curve is a moving target. It cannot be relied upon in planning.

(adsbygoogle = window.adsbygoogle || []).push({});