Tanzania's interconnected grid system has an installed capacity of 773MW, of which 71% is hydropower. The largest hydropower complexes are the Mtera and Kidatu Dams and they are situated on the Great Ruaha River. The Mtera Dam is the most important reservoir in the power system providing over-year storage capability. It also regulates the outflows to maintain the water level for the downstream Kidatu hydropower plant. Thermal generation in Tanzania currently relies on imported Heavy Fuel Oil (HFO); Jet A (aviation) fuel and diesel.
The installed capacity of the hydropower facilities are: - the Kidatu power station, which has the capacity of 204 MW; - the Kihansi power station, which has the capacity of 180 MW; - the Mtera power station, which has the capacity 80 MW; - the Pangani power station, which has the capacity of 68 MW; - the Hale power station, which has the 21 MW; and - Nyumba ya Mungu, which has the capacity of 8 MW The total capacity of hydropower generation is 561 MW.
The installed capacity of the thermal power facilities are: - the Tegeta power station, is privately owned and operated by Independent Power Tanzania Limited (IPTL), possesses the capacity of 100 MW; and - the Ubungo power station, has been owned by TANESCO, but, operated by Songas until privatization in June 2004, has the capacity of 112 MW Tanzania also has around 30MW of thermal generation in isolated areas that are not connected to the grid.
Two private independent power projects (IPP's) which are connected to Tanzania's grid are IPTL (Independent Power Tanzania Ltd) with 100 MW installed capacity and SONGAS (Songo Songo gas project) which by the end of 2004 had 120 MW capacity, although more gas turbines would have been installed to increase the capacity to 200 MW before the end of year 2005. Tanzania also imports 10 MW of electric power for Kagera Region from Masaka substation in Uganda while Sumbawanga, Tunduma and Mbozi districts receive about 3 MW from neighbouring Zambia. Bulk supply of electricity is made to Zanzibar from Ras Kilomoni substation at the Indian Ocean coast in Dar es Salaam.
There are several diesel generating stations connected to the national grid in Dar es Salaam, Mwanza, Tabora, Dodoma, Musoma and Mbeya. These possess an installed capacity of 80 MW but they effectively contribute about 35 MW due to running problems. Some regions, districts and townships are dependent on isolated diesel - run generators (Kigoma, Mtwara, Lindi, Njombe, Mafia, Mpanda, Tunduru, Songea, Liwale, Ikwiriri, Masasi and Kilwa Masoko). These have installed capacity of 31 MW but they effectively contribute about 15 MW due to aged machinery and lack of spare parts.
The output from generation plants is transmitted and distributed to mainland Tanzania with the following transmission lines: - 2,986 Kilometres of 220 kV transmission line - 1,971 km of 132 kV lines - 554 km of 66 kV lines
Majority of the population that receive electricity live in urban areas, and are concentrated in Dar es Salaam. The city consumes about 50 percent of power generated, while rural areas only receive a small portion of power. By the end of November, 2004 only 18 district headquarters were yet to receive electrical power, namely, Ngorongoro, Simanjiro, Ludewa, Biharamulo, Ngara, Serengeti, Kasulu, Kibondo, Urambo, Ukerewe, Utete, Namanyere, Bukombe, Uyui, Kilolo, Mbinga, Namtumbo and Kilindi.
Plans are underway to electrify Biharamulo, Ngara, Serengeti, Ukerewe, Urambo and Rufiji by 2005 while funds have already been secured for electrification of Bukombe, Kilindi and Simanjiro district headquarters before the end of 2006.
The country faces a major challenge of providing 90 percent of the remaining population access to electricity. This requires huge investments, hence the need for both international and local investors to participate in expanding the country's power sector. As the country is becoming more and more focused on providing electrical power, the need for new capacity is increasing rapidly. By the end of 2004 the maximum demand was 510 MW and was expected to increase to 600 MW by the end of 2005 in the case of power sector expansions.