**4.4 Geothermal energy**

54 Renewable Energy – Trends and Applications

Dodoma 6.1 6.0 6.1 5.7 5.6 5.8 5.7 6.0 6.3 6.4 6.5 6.2

D'Salaam 5.2 5.3 4.9 4.0 4.3 4.4 4.4 4.0 4.9 5.1 5.8 5.6

Iringa 6.0 6.1 5.7 5.9 6.2 6.3 6.1 6.6 6.7 7.0 6.7 6.2

Kigoma 4.3 4.5 4.9 4.3 4.4 4.8 4.3 4.9 4.9 4.7 4.1 4.3

Mtwara 4.4 4.6 4.3 4.0 4.4 4.4 4.5 4.6 4.9 4.9 5.2 4.8

Musoma 5.4 5.0 5.4 5.4 5.4 5.0 5.2 5.4 5.4 5.4 5.7 5.4

Same 5.6 5.5 5.6 4.7 3.6 3.8 4.0 4.1 4.6 5.0 5.4 5.6

Songea 4.2 4.3 4.2 3.9 3.9 3.6 3.7 3.9 4.4 4.5 4.5 4.4

Tabora 5.6 5.5 5.8 5.4 5.6 5.5 5.1 5.7 5.6 6.0 5.2 5.4

Zanzibar 5.1 5.2 4.9 4.2 4.4 4.7 4.5 4.8 5.1 5.3 5.0 5.0

Table 9. Mean monthly Daily Insolation totals in kWhm2/day for period of ten years [source

Wind resources can be exploited mainly in areas where wind power density is at least 400 W/m2at 30 metres above the ground. Continuing technical advances has opened up new areas to development, Because of the sensitivity of the potential of the value of the wind speed, the determination of specific sites for wind energy projects depends on accurate meteorological measurements, and sites measurements etc. Even in the best sites, the wind does not blow continuously. Thus, it can never achieve the 100% required for electricity generation. Wind energy potential in Tanzania, wind power densities are given

Wind farms for commercial plants appear promising at Makambako and Kititimo in Singida region as well as Mkumbara, Karatu and Mgagao. Areas along rift valleys, the southern high lands and along Lake Victoria are reported to have some possibilities of potential wind

Over the years, wind energy resources in the country have been used for wind mill to pump water. Less was been done in electricity generation. However with the availability of policy and renewable energy promotion program, emphasize now is toward utilization of wind energy in electricity generation. Number of wind mills available in the country is given in Table 11 and a photo depicting a wind turbine in Itungi village in central Tanzania is shown in Figure 1. The wind turbine is used to generate electricity for water

**MONTHS** 

**Jan Feb Marc April May June July August Sep. October Nov. Dec** 

**Station** 

A.H. Nzali 2001]

in Table 10.

sites.

pump.

Geothermal energy tends to be relatively diffuse in nature that is why it is difficult to tap. Geothermal heat is concentrated in regions associated with the boundaries of tectonic plates in the earth's crust. Eastern lift valley and Western part of lift valley is the area where availability of geothermal sources has been located. It has been established that on average, the temperature of the earth increases by about 3oC for every 100m in depths.

The potential of geothermal is highly dependent on the results of the resources exploration survey, consisting the location and confirmation of geothermal reservoir, with economically exploitable temperature, volume and accessibility. There is some potential of geothermal resource in the country. Currently, the existing potential is being assessed by the government through the Ministry of Energy and Minerals (MEM). A geological survey to establish the potential has been conducted since 2006. The project is assessing the geothermal potential at Songwe west of Mbeya city, Southern Highland. The estimated geothermal potential is about 1,000 MW. Geothermal power is relatively pollution free energy resource which can contribute much to the energy mix of the country if commercially exploited


Table 10. Wind Power Densities [Source Mmasi et al., 2001]
