## 1 Introduction  
Mozambique is a southern African country that possesses considerable water resources and hydropower potential through thirteen major river basins in the direction from south to north: Maputo, Umbeluzi, Incomati, Limpopo, Save, Buzi, Pungwe, Zambezi, Licungo, Ligonha, Lurio, Messalo and Rovuma. Mozambique is a downstream country and nine of the fifteen major basins in the Southern African Development Community (SADC) region are shared with other countries. High river discharge and steep gradients provide a high potential for the development of hydropower schemes of all types, from pico- and mini- to small- and large-scale hydropower plants [1,2]. The current scenario of electricity access in Mozambique is not very favorable to eradicate poverty because the rural areas still have a low rate of electrification of 27%; in comparison in Sweden the rate is 100%. The rate of electrification in the urban areas in Mozambique is about 67% and the national electrification rate is 40%. With higher energy potential resources (coal, natural gas, renewable energy resources) Mozambique still has low electricity consumption per capita of about 443 kWh [2,3]. Figure 1 shows the electricity production and consumption over the last eighteen years. Today in Mozambique the average energy consumption is 12 billion kWh. Hydropower is considered to be a very attractive form of electrical power generation for several reasons: it is one of largest sources of electricity in the world, the electrical power output takes only a short time to produce, it is always available since it represents renewable energy, and it is dependent upon water being available in large amounts. Hydropower represents one-sixth of the electricity generated globally and 97% of the total electricity generated in Mozambique [2]. Access to electricity is one of the instruments for achieving adequate social and industrial development in a society, yet about 1.3 billion people in the world are living without access to electricity. In Mozambique, there are around 20 million people living without electricity access and in poverty, out of which 85% live in rural areas [1,3,5]. The current figure regarding hydropower potential in Mozambique is highly attractive, being estimated to be at an 18,000 MW level, although only roughly 2200 MW of it has been developed in a manner providing it access to the national grid shown in Figure 1. To meet the needs that exist, the government of Mozambique has made rural electrification a major component of its development program. In addition, it has liberalized the energy sector of the country and an influx of direct foreign investments into hydro-projects within Mozambique has followed since 1997. Rainfall and topography offer greatest hydropower potential in Mozambique to the Zambezi River basin, at sites such as Cahora Bassa and Manica (Mavuzi and Chicamba with 80 MW of power output) on the Revue River. Together these have a generating capacity of about 2200 MW, of which Cahora Bassa provides 95% of the total hydropower produced in Mozambique. Figure 2 illustrates the total renewable energy including non-renewable energy such as coal and natural gas and good hydropower potential depending on the province in Mozambique. Rainfall and topography offer the greatest hydropower potential in the Zambezi River Basin at sites such as HCB and Manica (Mavuzi and Chicamba with 80 MW of power output) on the Revue River, as shown in Figure 3 [1, 2, 3, 6]. Climate variation impacts the use of hydropower and represents big challenges to the water resources sector in Mozambique. In Africa in general, and especially in Mozambique, water supply systems are poor and the government is already strained to deliver this resource to the population. Climate change will further complicate management of most of the systems in the future.