Electrical Power in Africa: Challenges and Opportunities
Written by Bruce H. Krogh and Hedda R. Schmidtke
Just as the telecommunications industry in developing countries has leveraged the latest mobile technology to leapfrog beyond aging legacy systems in developed countries, Africa offers intriguing possibilities to deploy and interlink the latest and most innovative energy technologies to create an energy infrastructure that is highly distributed, heterogeneous, robust, and sustainable.
Africa has been called the last investment frontier. While the United States and Europe have been struggling to recover from the economic downturn of 2008, the International Monetary Fund reports that the economies in over 20 countries in sub-Saharan Africa have grown an average of nearly 6 percent per year during the past five years. It is anticipated that these rates of growth will continue for the foreseeable future.
Economic and social developments are still limited, to be sure, by a straitened energy situation. Only 24 percent of the population of sub-Saharan Africa has access to electrical power, according to the World Bank, and many regions that do have power are plagued by rolling blackouts. Moreover, the problems of the oil-rich African countries are well known: Having energy resources does not necessarily translate into wide access to reliable energy.
Despite this, there are bright spots emerging on the energy landscape in Africa, and there is reason for optimism that Africa could soon become one the most interesting and productive regions of the world from the perspective of innovation in the generation and distribution of power.
Mature power systems in advanced industrial countries are built around the century-old paradigm of large-scale generation. The economies of scale offered by these systems, which rely primarily on fossil and nuclear sources, are increasingly seen as offset by detrimental environmental effects. When it comes to introducing renewable energy into developed markets, much of the challenge has to do with the massive technological and regulatory infrastructures that have evolved to support existing systems.
In the developing world, mobile telecommunications have flourished in the absence of legacy landline systems; the absence of a pervasive existing energy infrastructure—and the absence of a cumbersome regulatory apparatus—offer the possibility of introducing renewable technologies from scratch. This can be done with completely new methods and paradigms for meeting demand for electricity with highly distributed and heterogeneous sources of energy.
A variety of renewable energy sources are being developed in Africa, including hydro, geothermal, solar, biogas and biomass gasification. Each of these sources offers particular advantages and are attractive in particular regions. A number of pilot projects are underway throughout the continent, creating islands of electrification at different scales.
In Uganda, the company Village Energy encourages local entrepreneurs to assemble micro-networked home solar systems, relying as much as possible on local resources. The Spanish company Trama TecnoAmbiental has put together multi-user solar grids in Senegal and Morocco. In Rwanda, a small utility-scale solar power plant has been operating since 2007, and there are plans for a much bigger, 250 MW plant. Diverse micro- and mini-scale hydro plants have a combined capacity of nearly 50 MW; plans are being developed to drill widely distributed tubes so as to exploit the country’s geothermal capacity, estimated at more than 300 MW; and municipal waste and peat reserves are being eyed as other significant energy resources.
In many parts of Africa, rural electrification is being achieved through a mixture of on-grid generation and dedicated micro-grids, including solar systems to provide low-voltage DC to satisfy to basic demands for lighting (typically LED) and mobile phone recharging. This is leading to an energy future in Africa based on a diversity of highly distributed small-scale generation. The heterogeneity and distribution of generation in Africa presents the opportunity to explore the application of new technologies and control strategies, the very concepts dominating discussion of the smart grid.
Crudely speaking, consumers in advanced industrial countries are accustomed to getting reliable power 24/7, which is mainly generated centrally and on a large scale in highly planned networks. Such consumers are proving reluctant to adopt and use sensing technologies to provide them more awareness of their energy use.
In developing countries, on the other hand, consumers are highly aware of their energy use and the vicissitudes of intermittent supplies. Generally, the electricity needed to charge vitally needed cellphones and personal computers is generated on a small scale in local, heterogeneous islands. Often such local networks or microgrids are the products of projects funded through development programs or climate change funds.
Technologies from past and present development projects coexist, creating a mixed landscape of power supplies, including a high proportion of renewable energy. Production capacities also vary greatly: Small-scale energy production can be profitable in developing countries as it allows access to information and communications technology. Even a handcrafted wooden windmill provides enough electricity to power local mobile phones, allowing farmers to sell their products at better prices.
While the grid in the developed world has grown from demand for home appliances—non-smart devices that require relatively large amounts of continuous energy supply, like refrigerators and washing or drying machines—the grid in the developing world expands to rural areas by the demand for smart mobile devices that need to be recharged. Consequently, even small amounts of energy are valued highly by customers, and we can expect those with connected mobile devices to be able to handle typical renewable-energy grid challenges, such as intermittent availability or voltage instability. But, mid-sized industry customers, who currently run diesel generators to bridge power outages, highly value energy as fuel prices increase.
The result is an archipelago of disconnected islands of medium-capacity grids, micro-grids, and home-brew “nano-grids” of mostly smart devices—that is to say, a smart grid in its infancy and an opportunity for exploring technologies far beyond today’s marketplace. A major challenge is to interconnect these isolated islands into an increasingly reliable and robust grid. One innovative way to achieve this is to let the grid switch between different topologies, like putting a household into a different micro-grid in case of a power shortage in its preferred grid. This would create a fabric of overlapping micro-grids, providing redundancy of energy.
The concept of redundancies can further be exploited to channel available power to priority users such as healthcare facilities. Doing this will depend on smart grid technologies to sense and predict load variations, and independently control local distribution accordingly. Such a smart grid can evolve in a bottom-up fashion through mobile information and communications technologies, rather than being designed in a top-down manner.
In order to make advanced sensing and control technologies economically feasible in the context of the developing world, we need technologies that can be produced at a low cost and are immediately profitable in a larger global market. One possible approach comes from the increasing demand for a wide variety of analog legacy monitoring and control components. Energy systems, like other industrial large investments, have a guaranteed operational life of many decades. Digital smart grid components could simulate a wide variety of such legacy components at a reduced cost.
In summary, Africa offers opportunities to explore not only technologies for renewable generation, but also technologies and strategies for operating this evolving energy landscape in smart ways that are tailored to the specific features and needs of Africa. The continent has given birth to innovations in communications and networked computing like mobile money, and in the same way, Africa has the potential to become one of the most fertile regions for smart grid innovations.
Bruce H. Krogh is a professor of electrical and computer engineering at Carnegie Mellon University where he has been on the faculty since 1983. He is currently Director of Carnegie Mellon University of Rwanda in Kigali, Rwanda, a new location of the Carnegie Mellon University College of Engineering. His research focuses on the design and application of distributed control systems, including strategies for optimal coordination of supply and demand in highly distributed energy systems. He is a Distinguished Member of the IEEE Control Systems Society and a Fellow of the IEEE.
Hedda R. Schmidtke is an assistant professor at Carnegie Mellon University in Rwanda and CMU Silicon Valley. Her main research interests are in context-aware mobile and distributed systems, with applications to mobile systems, smart spaces and smart grids for energy management. Before joining CMU-Rwanda, she was a research fellow and later research professor at Gwangju Institute of Science and Technology (GIST) in South Korea (2006 to 2009), and research director of the TecO group at Karlsruhe Institute of Technology (KIT), Germany (2009 to 2011). She holds a doctoral degree in computer science from the University of Hamburg, Germany.