FINDINGS

The findings are as follows:

1. Parkes' Anemograph data analysis (for 4 sites) was fairly inaccurate and could not really be used directly as an absolute indication on windpower potential.

2. However the Beaufort data correlated well with the Cup counter anemometer (cca) data.

3. Parkes' figure of 5 mph (2.24 metres/second) as the cut-in speed for the Casella Mark II cca was found to be accurate.

4a. The maximum useable energy by an impulse type Wind Energy Converter (WEC) was found to be very closely correlated to the average windspeed as obtained from a Casella Mark II cca, by the following formula -

E = 20.1 * (vcca)^1.50

where E is integral of windspeed cubed with time, measured at 2 metres above ground level over short grass; note that as above this is the maximum useable wind energy by an impulse type WEC; it is obtainable at a certain value of cut in speed (or vci) - see more below.

vcca is indicated average cca wind velocity at 2 metres above ground level over short grass cover.

This formula was found to be valid between vcca values of 0 to 5.00 metre/second at 2 metres height above ground level over short grass, for both monthly and for annual readings, for 13 sites throughout Tanzania (Mwanza, Mtwara, Tanga, Lindi, Kigoma, Mbeya, Songea, Dodoma, Zanzibar, Tabora, Dar es Salaam, Iringa, and Moshi).

4b. Additionally, the total available energy was also found to be very closely correlated to vcca, by the following formula -

E = 30.0 * (vcca)^1.50

This formula was found to be valid between vcca values of 0 to 5.00 metre/second at 2 metres height above ground level over short grass, for both monthly and for annual readings, for 13 sites throughout Tanzania (Mwanza, Mtwara, Tanga, Lindi, Kigoma, Mbeya, Songea, Dodoma, Zanzibar, Tabora, Dar es Salaam, Iringa, and Moshi).

This is of great value for dealing with aerofoil type WEC's such as fast propeller wind electric generators (small and large) and Darrieus Rotor WEC's.