Daniel Theuri, Senior Programme Manager,
Energy Programme, Practical Action in Eastern Africa
 

Abstract

The sub region marked by the tropic of cancer in the north and the Capricorn in the south define an area generally referred to as sub-Sahara Africa. It is home to about 733 million people, majority of who live in rural areas on subsistence agriculture.  However, most of the population are concentrated in the tropical belt stretching from east to West. It is characterized by a marked dependence on unsustainably sourced biomass energy and used traditionally and very inefficiently.
The sub-region is endowed with significant natural energy resources which unfortunately , little transformation from primary to secondary forms have taken place to improve access to modern energy services by the majority of the people. The distribution range and concentration of natural energy resources is somehow localized. Biomass resources are plenty in the equatorial region and a belt along the coast of West Africa all the way to Gambia. Hydropower is plenty in eastern and southern Africa where availability of adequate rainfall and relief creates the basic natural potential for exploitation of cheap hydropower. The eastern Africa rift valley stretching from Djibouti to Mozambique and its twin western branch through the Lake Tanganyika up to western Uganda holds lots of energy that can be exploited for the social economic development the region. Currently, Kenya and Ethiopia are exploiting the resource but on a small scale.  The distribution of fossil fuels also reflects geographical distribution with vast coal resources in southern Africa while gas and petroleum are found in the west coast of Africa. The continent being astride the equator in almost equidistance from north to south means it is well endowed with solar energy. Elsewhere, the continent is also rich in various energy minerals like uranium, thorium and other renewables like wind more pronounced at the farthest latitudes form the equator and a few pockets inland methane gas in the lake Kivu and  natural gas fields Angola,  Tanzania and Ethiopia.

For the purposes of this paper, only small hydro resources as a major source of renewable energy with potential to transform a large number of people is addressed.

Various countries classify small hydro resources respectively differently and according to relative sizes of their hydro potential. A number of countries however, recognize small hydro to be a range of various classes of hydropower that comprises of pico hydro at less than 5 kWe, micro hydro ranging form above 5 kWe to 100 kWe, mini hydro from above 100 kWe to less than 1 MWe.  The small hydro power plants range from 1 to 30 MWe. Small hydropower therefore refers to a whole range of plants or sites capable of developing less than 30 MWe. Anything above this is considered large scale.
 

Hydro Resources Statement

Hydropower, being a function of altitudinal head and volume can only occur in those areas where the datum difference occur or can easily be created and hydrology supports free flow if damming is not to be done. A close glance on the continent one will notice a generally low lying land mass on average 450 masl  gradually rising towards the eastern half where in Rwanda and Burundi,  parts of Uganda ,  Kenya highlands and Ethiopian highlands reach above 1750 masl. Consequently, the highland belt stretching from Ethiopian highlands through the east African highlands through to the southern Africa is associated with tremendous hydro potential. It is estimated that the continent holds 10% f the worlds hydro potential energy at 1100 tWh  most of it in Congo Zaire basin, Zambezi, the Nile, Ruvuma and Rufiji and thousands of smaller streams running down the ranges and mountains of Africa. It is estimated that Zaire drainage basin alone holds over 90% of the Africa hydro potential.

Small hydropower sites are generally more disbursed than the larger sites, which have a cumulative flow sites, but always at subsequently lower altitudinal datum. The smaller sites like the microhydros and the even small picohydros are more disbursed across a larger geographical area where they became accessible to numerous communities and individuals who wish to develop them. The River Tana in Kenya offers an example of such resource dispersal providing wider access. Originating from the conical formation and snow capped Mount Kenya, most of the streams originate from around 2500 - 3200 masl. The fast flowing streams down the steep slopes joining each other to form bigger rivers, which by 1050 masl have formed one river the Tana. The single river now cascades through some cataracts some of which have been developed into power stations feeding over half of the countries electricity peak demand. At around 1800 masl Mount Kenya is an almost circular with a diameter of roughly 65 kilometers then rising to over 5000 masl. This means streams fall 1400 meters in less than 20 km thus dissipating a lot of energy that can be harnessed for electricity generation.

Another important feature in hydropower sites in Africa is the occurrence of faultiness associated with volcanic formations   of the continents and associated with the Great Rift Valley and mountain especially in eastern Africa sub region. Wherever these faultlines occur, they are areas of less resistance and often waterfalls occur along these faultlines.
 

Status of exploitation

The huge resource earlier indicated as 10% of the world potential, is concentrated in few countries within the tropics. Most of the countries are poorly served with electricity and have a low per capita consumption as low as 80 kWh and the sub Sahara countries averaging 350 kWh compared with 3750 kWh for Europe. The rural areas are have generally been neglected with connection to the national grid averaging more averaging less than 4 % while  urban areas average 40% in the four east African countries of Kenya, Uganda, Tanzania and Rwanda. The low rates of connection are a source frustration for many waiting to be connected to national grids. In Kenya, the connection rates grew on average 5.5 % in the last 10 years.
 

Challenges associated with the technology
 
Wealth and energy are interlinked in a vicious cycle. Wealth would allow one to invest in an energy system or advance the current one through efficiency gains and upgrading technology. Lack of wealth on the other hand has made people dependent on traditional sources which are currently being mined as opposed to sustainable yield. One of the most serious challenges facing Africa is creation of new wealth commensurate with the population growth. The forecasted economic decline by the continent and current destruction of its natural resource base exacerbate a serious situation where more than approximately 670 million people live on less than 2 dollars a day. Although energy and energy services by themselves are not the solution, they are critical in the overall equation addressing poverty reduction. The livelihoods of many small-scale producers relying mainly on biomass energy are under threat because of inefficient production methods and diminishing resource base. Diminishing returns and poor or low efficiency is driving more and more people into the poverty trap.  The concerted effort towards improving overall economic efficiency and generating new wealth both at local and national levels will depend on how well modern energy services are delivered to the users and the relative costs involved. Small hydros, by their very nature of being widely disbursed can be part of the solution to meeting the modern energy needs of many people.

The challenges facing small hydropower exploitation are many and the few narrated here are just part of a bigger and complexity of the problem being country specific. Among these are:  (1) access to appropriate technologies especially in the mini, micro and pico hydro categories ,  which because of small heads and low volumes or very high heads and low volumes pose special challenges. (2) lack of infrastructure for manufacturing, installation and operation. Most of the countries in the sub region do not have any facility to manufacture even the most rudimentary turbines or parts that might be critical in maintenance of the schemes. Example is the availability of capacity manufacture of high-density polyvinyl pipes that can serve as good penstocks for the pico hydros. Few countries have these products and as such, exploitation of otherwise simple sites has been hampered by this deficiency.  (3) lack of local capacity to design and develop small hydropower schemes for areas sometimes considered too remote. Generally, most of the countries lack specialisation to undertake feasibility studies, detailed studies that would include detailed design and costing of the schemes to make a meaningful impact on utilisation of small hydro sites. (4) A major challenge to the development the small hydros have been the low electricity consumption associated with the sub-region.  From an economic point of view, Low consumption of generated power means that the investment cannot make adequate return on investment in time for the projects to remain viable and hence they all fail to lower the cost of the generated power. This problem is not only bedevilling small hydros but also the electricity sub sectors of the sub Saharan economies where consumption of the generated energy is so low that it is often not making an impact on human drudgery and burden especially in rural areas and the peri - urban areas. Unfortunately, even with low consumption, efficiency in transformation and use is still poor hence; the affective power that contributes to growth is so low.
 
The barriers limiting widespread use of hydropower are also many although there has been a significant shift in the last few years in most of the countries.  Most of the policies are yet to be fully reformed to provide appropriate mechanisms for delivering electricity cheaply and reliably to all sectors of economies in sub Saharan Africa. In Kenya, for example, the reformation process is raising doubt as to the capacity and potential of the market forces alone to determine cheaper energy costs. The cost of electricity has been increasing hurting the poor most, while many had been made to belief that reforms would lead to cheap energy. Another major barrier is the technical limitations being encountered especially with the entry of free players in formerly centralized systems. Development of  appropriate technical specifications ,  standards and codes for generation and distribution is yet to be undertaken even in countries where reforms have been  almost compete.. Kenya is an example of such level of reforms, which have not moved in tandem with appropriate grid and non-grid specifications, standardization and harmonization. The outcome of such scenario is development of good policies but no effective changes on the ground.
 
Lack of capacity to mobilize adequate resources both internally and within the official development assistance to develop those small hydros especially for rural areas, which have historically been neglected in development and planning, is a major barrier. The fact that the rural and urban poor needs mechanisms for ensuring affordability for energy services have been cited as the main push for decentralized energy supply. The conventional delivery system have had very strong government presence attenuating legacies of  post colonial establishments like monopolistic structures that have continued to dominate the power sub sectors.

Of course a major barriers facing the small hydropower schemes like any other investment is the impact of poverty especially in limiting peoples capacity to develop local resources This sub region is among the most poverty stricken in the world with a number of countries among the twenty poorest countries on earth. Even the smallest of the schemes possibly costing only few thousand dollars becomes a major project for the poor as they struggle to meet other social and individual obligations on society.
 

Small hydros in scaling up energy access agenda

The small hydros are part of the solution that can contribute to increasing access to modern energy services. They are versatile in terms of application and can drive multiple outputs using the same turbine (Multi Functional platforms) and can be configured to address local energy needs better than bigger systems. For example, a community in need of water supply as the primary energy service can have the small hydro as a motive driver for a water supply scheme while other uses become secondary. In other areas, grinding of grains might rank as an important energy need and the small hydro system can be designed or configured to address the grain milling end uses primarily.

 In providing increased access to modern energy, an agenda, which has gained momentum after the WSSD meeting in South Africa and the scaling up access agenda as, promoted by among others UNDP, one needs to address a number of factors, which are well cited in printed matter. However, an important consideration is not adequately emphasized. This is what I would like to call post meter issues and considerations. When a community scheme is designed to provide just electrical energy as opposed to meeting some energy services  we end up with a scenario where power posts are erected near of houses or buildings without due attention to what services are of priority and should be addressed. Cases of rural electrification only meeting lighting needs are many while good lighting will only improve comfort in the e vicinity. But designing system and schemes addressing specified energy services or even non energy services can increase tremendously the amount of electricity consumption thus raising the economic rating of the scheme in the he overall energy matrix. A multi functional approach is meant to address this very fact whether one is looking at household level or community energy service needs. A similar holistic approach when designing small hydro schemes is critical in scaling up the small hydropower usage in areas where electrification is needed and the potential exists.
Considering that the wet habitable areas where rivers abound are the same carrying most of the population and bio diversity, then a whole question of factoring in other energy and non-energy services into the overall design of small hydros become critical. Environmental degradation associated with the biomass harvesting or exploitation as one would call non-sustainable use of the biomass resource is affecting rural lives and impacting negatively on social growth. Loss of soil fertility for example reduces food productivity, poor use of biomass is leading in increased poor health due to in door air pollution, women and the girl child are seriously affected by decreasing availability of biomass. This has s tended to increase drudgery and burden and cost in terms of time and physical efforts. Water supply is the other example affecting communities with a gender dimension. The modular approaches in small hydros and especially the smallest of the schemes can be able to address a number those issues and when factored in the design of the scheme will make the project cheaper in the long run and competitive with already highly subsidized grid schemes.

Finally, for the purposes of configuring a scheme size for communities, a village and house level needs assessment targeting specific outcomes like MDGs and PRSPs needs to be well understood and done. Special efforts and capacity may need to be developed to empower the communities and the local institutions doing the needs assessment to look beyond the traditional view of electrification, where post meter events did not overly concern key players. Lessons learnt by ITDG-Practical Action in their pico and micro hydropower projects provide useful insight. The Pico hydro being small in nature can only drive specific end uses where they are optimized for efficiency and utility considerations i.e. meeting maximum number of people served. The main use is lighting but targeting kerosene substitution as the primary goal. Hence, each household was served with one or two lamps to replace the inefficient hurricane lamps and naked wick lamps running in kerosene. The picos have been successful in meeting this policy objective and the schemes register a much higher plant factor than the bigger micro hydro schemes.  On the other hand, the community micro hydro scheme was designed to drive a number of end uses in a business center to provide services and create income. This again has had varied success depending on where one is looking from. From a utility point of view, the plant factor is still very low at less than 40 %, which means that despite the services being nearer to the people the scheme has a lot of idle capacity thus driving the cost of energy service higher. Mark you from a social point of view this is a very successful project which has brought useful services closer to people like welding refrigeration,  battery charging ,  small secondary business like extended selling and buying of goods and services thus reinforcing the community well being and bringing infrastructural services closer to people. It has even improved communication and security in the area due to increased use of mobile phones by the community. The same scheme, going by the expressed needs by local women who in a pre- project needs assessment had indicated their primary interest was the project to help them in reducing burden of water fetching. The donor and the key players including men within the project wanted electricity. The day the water supply component of the scheme will be done , the scheme will  reach new dimensions in terms of services and reducing drudgery thus fleeing more people an mainly women to engage in other more productive work.

A project proposed by UNEP and ITDG-Practical action in eastern Africa will among other things understudy the operational and technical features of business / productive oriented approach in small hydro projects. It is estimated that the smallest sizes of a productive scheme capable of delivering multiple services are within 35 kW - 50 kW range. As the systems sizes get smaller, they provide better only some services. As an example, the 14 kW Tuungu Kabiri community micro hydro in Kenya is seriously limited for some applications like welding and can only be done when other users are off line.

In conclusion,  the small hydropower schemes are a viable option in increasing access to modern services that can have a positive impact on village level type of development However, in designing these small schemes there is a need to match service needs with the power to ensure the schemes are meetings as many  priority needs as possible. People often do not care what energy systems is in place so long as the service needs are met. Awareness of the potential and types of technologies that can be used by communities then becomes less of a requisite and developing local capacity for assessment, designing developing, installing operation and maintenance takes a more centre stage.

My last word is that with such a high-unmet demand for electricity and services that electricity provide in most of sub Sahara Africa, there is a great opportunity for business in the region.
 

References:
 

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Disclaimer,
The views expressed in this article are purely those of the author and do not necessary reflect the views or positions expressed by any organization, persons or body.