Received date: July 19, 2017; Accepted date: July 31, 2017; Published date: August 05, 2017
Citation: Zhang J, Adu D, Fang Y (2017) The Potential for Small Hydropower Plants in Ghana. Innov Ener Res 6:166.
Copyright: © 2017 Zhang J, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Visit for more related articles at Innovative Energy & Research
Several resources and efforts have been devoted into many studies concerning the Small Hydro Potential (SHP) sites in Ghana, but still not a single of these potential sites has been developed. The country has been experiencing power crises in recent years and has resorted to the development of thermal power as supplement to the old hydropower source. The significance of renewable energy such as small hydropower in the generation of sustainable power based on its capacity to contribute towards alleviating acute shortage of rural electricity supply in Ghana has been discussed. A reasonably complete small hydropower technology review has been presented. Electricity supply to the rural communities’ situation in the country has been presented and, in general, the country’s level of electricity access is very low combined with various challenges. Small hydropower technology has been discussed as one of the promising spread out power generation system for rural electricity supply in the country. In spite of the challenges in the acquisition of data, this paper has shown that there are many important hydropower resources in Ghana with low installation level. Challenges hindering SHP technology development in the country have been identified and discussed, for instance those relating to technology, climate change, finance, and policy. This paper adds to the information base on SHP technology which is relatively missing in the country.
Energy; Small hydropower; Installed capacity; Potentials
Access to Energy is a crucial concern, openly associated with income and poverty. Many rural populations are still deprived of electricity, even though the use of modern energy has risen from almost zero for the lowest income quintile to 70% and to 90% for the highest income quintile  for some countries. Global energy demand is increasing. Increasing costs of fuel and concerns about air pollution have stimulated demand for renewable energy. Many prospective communities are carefully examining their renewable natural resources to determine if any is suitable for development. As a result of the advances in various technologies, energy sources that were once tagged as not feasible now find their way into the mainstream. In this regard, small hydropower has become a renewable energy source, easy to develop, cheap and environmentally friendly. These features have increased the value of small hydropower development and opened avenues for the new trend in renewable energy power generation  in addition, due to the financial requirements and the national budget sources, lack of a considerable number, and environmentalists strongly opposed to non-governmental organizations, large hydropower projects cannot be completed in the planning period, which led to the use of SHP in developing countries in the low investment cost, short construction period and environmental protection. Both developed and undeveloped countries have attached a lot of importance to small hydropower. Europe and North America have developed greater part of their hydropower potential. Alternatively, Africa, Asia and South America still have plenty of unused potential . Small hydro can be the cure for the inadequate energy in developing countries. In 2010, nearly 21,800 small hydropower stations were operational, that is in Germany (more than 7,500), Austria (2,590), Italy (2,303), France (1,900), Sweden 1,900), the Czech Republic (1,450). The total number of small hydropower stations is expected to reach 24,000 by 2020  in these developing Countries. From 2010 to 2020, the installed capacity of power station is expected to increase from 13.7 GW to 17.3 GW, and the annual power generation capacity will also increase from 49.3 TWh to 59.7 TWh. The annual growth rate of small hydropower generation should also reach a total of 21%., the strategic plan for small hydropower in European Union 27 [EU-27] from 2010 to 2020 is to increase the installed capacity of small hydropower by adding 2,100 small hydropower stations (with an average annual increase of 210 power stations) 3.62 × 106 kW (an average annual increase of 3.62 × 105 kW) and an increase of about 10.37 GWh (an average annual increase of 1.037 GWh) in the annual production of small hydropower. The Statistics and prediction of SHP installed capacity in the EU countries from 2005 to 2020 .
Ghana’s Electricity production has gone through several stages: beginning by means of diesel generators and stand-alone electricity supply systems possessed by industrial mines and factories, to the hydro stage after the building of Akosombo dam, and thermal supplement stage powered by gas and/or light crude oil at the moment. Power crisis has been one of the perpetual developmental challenges in Ghana, with growing harshness threatening the country’s economic growth and development [5,6]. Energy generation is a great concern to the Government of Ghana. The Volta River Authority (VRA) is a main power generation company, set up by the Act of Parliament in 1961 to provide Electricity to the people of Ghana since it is possessed by the Government of Ghana . The Volta River Authority (VRA) combines hydro, thermal and solar power plants to provide electricity to local and export markets. As a result of the energy sector reform, there stand other power generation companies privately owned and are called independent power producers. Famous among them include Ameri, Karpower, Sunon-Asogli and Cenit .
Reasonable price as well as consistent power supply is an important requirement for economic growth. Electricity from renewable sources can play an important role in the improvement of electricity supply in Africa . Electricity is essential for providing basic social services, including education and health, together with the powering of machines that support income generating activities that creates job opportunities and reduces poverty. The use of hydro power generation is likely to ensure energy security, which may be an effective way to reduce poverty in Ghana. Ghana has been weighed down by insufficient energy supply leading to the energy crisis over the past ten years as a result of prolonged drought that affected the Volta River basin which happened to be the main power source of the country. It is therefore necessary to find additional sustainable energy supply to fight the country’s energy crisis. There are about 795 MW Small Hydro Power (SHP) potential in the country that can be connected to increase the energy supply in the country . This paper reviews the river potentials for small hydropower construction in Ghana, taking into account their river heads, length, width as well as the flow rate.
The Economic Community of Western African States (ECOWAS) renewable energy policy is a regional document demanding the success of renewable energy targets of 19% of installed capacity as well as 12% of generation by 2030 devoid of large hydropower. The Policy contains an implementation plan for accomplishing the objectives based on six steps. The timeline of the policy also requires all member countries to have finished their NREP by the end of 2013, with the aim of fulfilling their five-year rolling action plan starting in 2014 . The economic growth in Ghana reduced suddenly to about 4.2% in 2014, from that of 7.4% in 2013. This was as a result of, Natural gas supply disruptions from Nigeria, rising inflation, interferences in power supply, devaluation of the Cedi as well as Manufacturing and oil production from the offshore Jubilee field. Compared with other countries related also with using energy and oil and gas investment opportunities, Ghana has a long history as a stable democracy and an attractive investment environment . With the construction of the Bui hydropower plants, Ghana’s total installed capacity has reached 2,837 MW making electricity reach 74% of the national population. Nevertheless, the reliable capacity is about 2,515 MW. Additional 240 MW generation capacity increase was anticipated in the third quarter of 2014 after the Kpone thermal power plant was commissioning, bringing the total installed capacity to 3,077 MW (Figure 1).
The expansion of power generation capacity, expansion of supply network, the power supply reliability, reduced technical and commercial losses and the use of natural gas as raw material are key areas of attention in the power and energy sectors of the Government of Ghana to maintain economic growth . The total energy production, consumption, energy needs, and peak demand are increasing in Ghana as shown in Table 1. The estimated Electricity Equivalent Peak Demand for the year 2014 was 2,179.5 MW signifying an increase of 236.6 MW as well as a growth of 12.2% above the 2013 actual peak which was 1,942.9 MW  as can be seen in Table 1. The increase arose because of mines, industrial customers, residential and new loads coming from rural projects. Energy is Ghana's daily news, which has become headlines for years. Due to the economic growth over the past decade, energy demand has increased speedily. The present level of energy generation is inadequate to produce a reliable supply of electricity to the entire country. The industry needs sufficient energy levels to produce goods and services, as well as the need to promote reliable power supply to domestic consumers devoid of load shedding. Although some power plants are under construction with some others in the planning stage, consumers are still not likely to enjoy consistent supply in the near future considering the rapid growth in demand. The Vision 2020 by Ghana includes the National Electrification Scheme (NES) with the target of 100% electrification by the year 2020 (as contrasting to the currently 72%). This has Compel policymakers not to focus on the expansion of generating capacity plans alone but also to promote the comprehensive development of alternative energy sources as well for general and stable development of the energy sector, based on a mix of sources, including renewable energy. The government of Ghana’s main objectives for energy sector is to develop the country’s oil and gas reserves for domestic use (together with the generation of electricity) and for export, in addition to the provision of grid access for the entire population once generation capacity allows. Power generation capacity of 5,000 MW was the expectant target by the Government of Ghana in 2016 (up from about 2400 MW currently). Simultaneously the Government aims to reduce the huge subsidies on fuel and electricity which at the moment brand the power sector (Figure 2) [15,16].
|Name||Installed Capacity (MW)||Reliable Capacity (MW)||Energy Type|
|Aboadze T1||330||300||Natural Gas|
|Aboadze T2 (Tico)||220||220||Natural Gas|
|Osonor (Cent)||126||120||Natural Gas|
|Takoradi 3||132||120||Natural Gas|
|Tema Mine Reserve Plant||80||40||Natural Gas|
|Takoradi (TAPCO)||320||320||Natural Gas|
|Solar Western Region||20||20||Solar|
Table 1: Electricity installed capacity in Ghana (MW) .
This part of the paper outlines the potentials of some rivers with small hydro site in five regions of Ghana, such as Brong Ahafo, Volta, Asante, Eastern and Western Regions that can be used to establish small hydropower to help relieve the country of its electricity crisis (Figure 3) . All the following sites in the country such as Kokuma Falls, Randall falls, Wurudu falls, Kintampo falls, Tsatsadu falls and Kwanyaku are potential locations for sitting grid connected small hydropower plants. Hydropower is dominant, both in terms of cumulative installed capacity and capacity increase. However, momentous future growth forecasts small hydro energy. It is necessary to recollect that the further the future scenarios are projected, the more speculative they become. The projections for 2050 are fundamentally very ambitious, particularly in a fast-growing market such as Africa [18,19]. The multipurpose program combines electricity production with other water uses such as irrigation, flood control, recreation and drinking water supply. Although such programs can be more complex, they can also help projects to become economically viable and accept to the local communities. Small hydropower stations account for about 10% of global hydropower potential. Africa has 588 small hydropower operations below 10 MW and the average size of 2.5 MW (total of about 1.5 GW). Important Small hydropower potential exist in Africa, with a potential of approximately10.51 MW in the 13 West African countries that have been investigated in which they have conducted surveys on them .
Ghana defines small-scale hydropower as up to 1 MW with medium scale ranging between 1 MW to 10 MW and large-scale between 10 MW to 100 MW . There are currently no small hydropower plants in Ghana. According to the Baseline Report for Small-Scale Hydropower in the Economic Community of West African States Region a total of 85 potential sites of up to 30 MW. Small hydropower total potential capacity of 110 MW  is found in Ghana. In considering those up to 10 MW capacity alone there are 17.42 MW small hydropower potential comprising two sources: the Hydrological Service Department of Ministry of Works and Housing said this consist of 69 sites (<2 MW) with a total potential of around 15.18 MW; then to the Energy Foundation, 12 sites (<1 MW) with a total potential of 2.24 MW [21,22]. Feasibility study have been completed on the following sites such as Boumfoum falls (150 kW), Willi falls (1000 kW) Kokuma falls (75 kW), Randall falls (160 kW), Wurudu Falls (25 kW), Tsatsadu falls (320 kW) and Kwanyaku (130 kW) potential capacity . The Energy Commission has initiated actions to develop the country’s renewable energy resources; specifically small hydropower. The Energy Policy states that the small hydropower potential is limited to 21 potential sites with generating capacities ranging between 4 kW to 325 kW . The Table 2 shows the summary of the rivers in the country with their net heads and estimated hydropower capacity. The Government has realized the benefits of a more sustainable approach to agriculture therefore, created a policy to develop small hydropower and small scale irrigation facilities with the aim of boosting agriculture in the rural areas. There are several rivers with the potentials for small hydropower development in the country which can generate electricity with an installed capacity of between 4.5 MW to 42 MW (for instance River Ankobra, Pra and Oti). Small scale hydropower is expected to be built on the Ankobra River in the Western Region of Ghana. Feasibility studies have shown that three areas on the river such as Maham, Tarkwa-Breman and Nsuaem are potential sites for the development of small hydropower .
|Region (kW)||Small Hydro Site||Net Head (m)||Estimated Generation Capacity (kW)|
|Brong Ahafo||Kokuma Falls||23||75|
|Brong Ahafo||Randall Falls||40||160|
|Central||Kwanyaku Water Works||5||130|
Table 2: Small hydropower potential sites found in Ghana with their installed capacity .
Kokuma Falls is located in Kintampo the Centre of Ghana in the Brong Ahafo region. It is about 500 km from Accra the Capital city of Ghana. Kokuma Falls has a catchment area of 78 km2 with the head of 23 m and design flow rate of 400 l/s adequate for plant capacity of 75 kW. It can generate electricity of 375,000 kWh for communities within 5 km from electricity grid with difficult access road to powerhouse. Most of the people in this area are farmers who need electricity to process some of their products and more importantly, a Health training institution which needs electricity for their activities.
The second one is the Randall falls also located in Kintampo in the Brong Ahafo region of Ghana. It has a head of 40 m in two drops with design flow rate 200 l/s sufficient for plant capacity of 160 kW (grid connected). Randall falls has an annual energy generation capacity of 810,000 kWh for its communities within 5 km from electricity network (Figure 4).
Wurudu falls is located in East–Akim of Eastern region of the country roughly 120 km from the country’s capital Accra. It has a catchment area of 3.9 km2, 40 m head in two drops and a design flow rate of 80 l/s suitable for small hydropower plant of 25 kW.
Tsatsadu Falls is located in Alavanyo in the Volta Region of Ghana approximately 200 km away from Accra the capital city of Ghana. It has a catchment area of 40 km2 with head 43 m falls plus 37 m rapids and design flow rate of 500 l/s suitable for grid connection of 320 kW. It also has an annual power generation of 1.2 GWh Appropriate for grid construction (Figure 5).
The Kwanyaku River has a Small Hydropower Potential at Agona Kwanyaku in the central region of Ghana approximately 110 km from Accra the capital town of Ghana. It has a maximum height of 29 feet and length 337 feet and adequate head and flow rate 200 l/s for plant capacity of 30 kW or more. The river does not dry up during the dry seasons and suitable for small hydro turbine installation (Figure 6).
Also, the Energy Commission has identified some additional potential sites on the Black Volta, White Volta, Tano river and Pra river with a total capacity of about 840 MW that are yet to be developed. Extremely large small hydropower resources are available in many parts of the country, especially in the Brong Ahafo and Volta Regions where electrification rate is low. Feasibility and pre-feasibility studies have been undertaken on some of the sites. This data can be shared with potential investors.
As stated by Nkrumah, the Volta Project was made-up to become one of "the new ‘places of Pilgrimage’ in this present Age of Science and Technology," motivation to the rest of the continent and the world alike. "It will make available power practically at the door-steps of businessmen and entrepreneurs in urban areas and offer them a powerful stimulus for the modernization of existing industries and the development of new ones. “But now, the six turbines of the dam are struggling to produce 67% of the country’s power like the way they used to do in 2012. Compared to the rest of the continent, Ghana has one of the highest rates of access to electricity. It was ranked second to South Africa in 2012 as presented by the World Bank Data but the power cut still persist .
Large hydropower plants are seen as cheap energy generators in Ghana. Most communities within the proximity of potential small hydropower sites are grid connected and therefore small hydropower setting out is not cost competitive (Figure 7). This is particularly attributable to high capital costs. Insufficient information also increases investment risks, especially in the case of unfavorable flow duration curves. In some cases, a particular site could be used to stimulate socioeconomic activities other than power generation, for example irrigation, tourism, ecological education, religion which would avoid the displacement of people, animals and flooding.
An additional important concern is the absence of a regulatory and legal framework for renewable energy sources use and its development by way of little or no economic incentives prepared to entice investors to small hydropower, even though feed-in tariffs for renewables was planned for 2013.
Mention must also be made on the limited local technical expertise. The country also lacks personnel that have the skills and technical know-how on small hydropower construction. Especially the designing of the appropriate turbine to fit the area and as well as its management.
Lack of Funding: High cost for the development of sites, Turbine design cost, the investment cost of construction and labor cost as well as inadequate financing of civil works possibly will lead to the abandonment of the projects
Despites these challenges, the Government of Ghana are still determined to develop some of its small hydropower sites in order to produce energy to feed the national grid. Technical regulatory framework to assist feed-in energy from Renewable sources into grid is being formulated and therefore Looking for technical and financial assistance for the development of potential small hydropower plants.
Although Ghana has all these potential rivers, not a single of the potential sites have been developed to support their small hydro generation. Despite the fact that the Government of Ghana is determined to develop some of its small hydro sites to generate power to feed into the national grid with the formulation of Technical Regulatory framework to facilitate feed in 2005, it is still not done (Figure 8). Feasibility studies has been completed on a chosen site in Tsatsadu in the Volta region which would have taken delivery of 30 kW turbine for the project Civil works beginning in May 2016 with the hope that it could have being fully completed by the end of 2006 but work has not been completed yet. For Ghana to achieve faster growth and transformation, the Energy sector should be seriously looked at. Identified sites with small hydro potentials should be built. Ghana’s energy policy over the years has concentrated on different renewable energy such as the efficient use of solar and wind in the national energy mix but is time to also pay much attention to small hydro. There are wide opportunities for private  investment in the energy sector in the form of IPPs and under FITs for renewable energy projects since the Government of Ghana target of 5,000 MW by 2015/16 coupled with the estimated requirement of an additional 4,000 MW of capacity over the next 20 years requires significant foreign investment, private capital, and technical expertise.
1. In carrying out the first mini hydro pilot projects in Ghana, middle or high head sites should be considered instead of low head sites. Low head sites are comparatively costlier to construct, besides they stand the risk of flooding. It is also suggested that by way of a piloting a project the Tsatsadu Falls in the Volta region or the waterfalls nearby Kintampo in Brong Ahafo must be taking into consideration.
2. Consideration can also be given to the low head sites in the Volta Region, particularly Likpe Kukurantumi, in case there are plans in setting up irrigation projects in that area. Since all the rivers there have a permanent flow all through the year. An additional hydro power plant can generate some energy to pump the water. Nevertheless, in depth analyses on the effect of flooding should be carried out by qualified hydrologists before proceeding with plans to construct dams of 5 to 14 m of head on these rivers, as predicted in some proposals.
3. Is advised to systematically review the potential for small or Mini Hydro Plants be done by the Ghana Water Company on their dams and weirs, taking into account the recent flow information along with the current power tariffs they have to pay.
4. The Government of Ghana in conjunction with the Energy Commission and the Public Utilities Regulatory Commission (PURC) has to make available a clear regulation and attractive price for supplying Energy into the national electricity grid in order to attract private sector investors and other renewable energy sources investors to invest into the small hydropower energy generation projects.
We thank National Natural Science Foundation of China form their financial support.
Jinfeng and Adu Daniel abstracted the paper and delve into the topic. All authors contributed towards the writing and editing of the manuscript.