Africa possesses great natural endowments in all forms. It has the advantage of an abundance of natural hydrocarbons. Africa has a significant percentage of the world’s oil production as well as large quantities of coal and gas [1] . Africa has abundant sunlight, wind as well as abundant land. Africa’s land includes the tropical rain forest which has carbon sequestration implications. The continent also has arable and affable land with a potential for biofuels. In terms of utilization, fossil fuels, biomass and hydro make up Africa’s most predominant energy sources [2] . There is however a different mix of resource endowments in the different regions and countries of Africa; almost all the geothermal resources in Africa are in East Africa, a big percentage of the hydro resources are in central Africa, significant wind resources are in the North and East as well as solar resources located in North and West [2] . There is more dependence on renewable energy sources by Eastern Africa and Central Africa than other regions [3] . Africa contains great energy options and is truly blessed with all the resources needed, both conventional and renewable energy sources. Tables 1-6 show the power projects in Africa in terms of the ones operating, in construction and

planned.

From the above tables, we see that West Africa has the most projects in operation with 892 projects. The region, however, lacks behind East Africa in the number of projects undergoing construction (61) and Southern Africa in the number of planned projects (682). We can see generally from the tables that Africa is making intentional progress as regards making energy available as the number of planned projects in all regions is comparable to the number of already existing projects as should be for the second most populous continent.

According to the United States environmental protection agency, Conventional energy sources typically refer to fossil fuels combined with nuclear fission involving uranium (3). Fossil fuels include crude oil, natural gas, coal etc. Nuclear energy may be differentiated in the sense that it does not involve emission of greenhouse gases. However just like fossil fuels, it involves mining, extraction as well as the storage of the long-term radioactive wastes. Renewable energy sources refer to sources that do not diminish but are restored by themselves between short periods. They occur freely in nature and are infinite supply. Examples include the wind, sun, waste material, heat (geothermal), organic plants etc. Green energy is a constituent of renewable energy sources. They reflect the sources that promote a lot of benefits to the environment. The Environmental Protection Agency (EPA) classifies green power as power generated from the sun, wind, geothermal, biomass, biogas, and hydroelectric sources that have low impact. The difference between all renewable energy sources and the subset that constitutes green power lies in the effects transmitted to the environment. Large hydroelectric resources for instance have trade-offs that relate to the environment like the effect on fisheries and land use. Another example of a renewable energy source not classified as green power by EPA is municipal solid waste. It is important to note that renewable energy sources are not the only class that occurs naturally. Non-renewable sources are also naturally occurring as they are within the surface of the earth. The difference is in the duration at which the sources replenish. Non-renewable sources are only available in finite amounts and thus can produce energy shortages in the near future [4] . It is then very clear to see why renewable energy sources are preferred to non-renewable sources. Figure 1 shows the total renewable energy consumption globally in terms of terawatt-hours per year while Figure 2 shows that for Africa alone.

Despite being heavily blessed with these natural endowments, research carried out in [1] and [2] showed that awareness of these resources and their utilization

is low. In [5] the utilization of renewable energy resources was explored for the purpose of achieving sustainable development in Nigeria. They adopted a survey approach by distributing questionnaires across Abuja, Nigeria. The results obtained from the data collation revealed that a large number of the respondents lacked knowledge of renewable energy resources and its utilization and adoption. The authors recommend the political commitment of the government towards renewable energy and developing an energy-efficient environment for the private sectors, which will in turn enhance the achievement of sustainable development goals. In [6] the application of renewable energy technologies was analyzed for the reduction of electricity poverty in the Southwestern region of Nigeria. To examine this application, data was collected by reviewing the opinions of 143 respondents with the aid of questionnaires. This was carried out in order to examine the knowledge of the residents towards the substitution of the national grid system with renewable energy. From the obtained results, it was discovered that a reasonable percentage of the population (38%) were unaware of renewable energy derived from biomass, wind, and solar heating. However, they possessed knowledge of energies from firewood, solar and large hydro. In addition, the bulk of the population was open to the introduction of renewable energy Technology, provided the government funds the operation. The authors urge the local and state governments in setting up plants, providing a sustainable environment for implementation, as well as educating both rural and urban dwellers about the advantages of such technology and how sustainable development can be achieved. Currently, there is perhaps no greater need for energy than in sub-Saharan Africa.

In sub-Saharan Africa, it is noted that just 42.8% of the population can access electricity [7] . This should not be as Africa is the continent with the highest renewable reserves in the world. The sub-Saharan Africa region is also the region that depends most on available natural resources in order to meet the region’s social and economic needs. Africa can also benefit from her status as a “latecomer”. The African Development Bank (AFDB) has put the spotlight on green growth to actively encourage a more sustainable and resource efficient development [8] . Research shows that a bi-directional positive relationship exists between energy and economic growth [3] . Wesseh & Lin [9] , showed that for every unit increase in capital, labor, renewable and non-renewable energy, Africa’s economic growth is boosted by 15%, 21%, 12% and 5%. Renewable energy in particular was also shown to have a significant role in Africa’s economic activities as it had an average estimated output elasicity gap of 0.41 to nonrenewable energy [10] . Health and education are improved in areas where there is electricity access [3] . While developing countries have poured in huge investments in their power supply and other infrastructures, Africa will be making her investments at a time when new technologies are readily available leading to more efficiency [11] . The continent should however not wait for technological change and should invest quickly as it is experiencing grave energy shortages. Renewable energy also largely contributes to the reduction of pollution locally and globally. Climate change constitutes a serious problem in our world today. Renewable energy sources produce little or no carbon dioxide or Sulphur dioxide as well as particulates which pollute the environment. In the present world, there are control measures to limit the effects of carbon emission in operations that involve it. Carbon Capture and Storage (CCS) is one of those measures. However, the cost of implementation of CCS is very high especially for a continent like Africa. The engagement of Renewable energy sources also reduces the pressure on the use of fossil fuels. This means that mining activities can also be reduced. Mining activities constitute environmental factors such as oil spillage. These have an effect on the surrounding environment. Oil spillage is a direct threat to life below water. The protection of life below water is one of the present world’s sustainable development goals.

Figure 3 and Figure 4 show the renewable energy electricity share globally and in sub-Saharan Africa.

Table 7 shows the progression of different renewable energy sources

consumption in Africa from 1965 to 2016.

It can be seen from the table that hydropower constitutes the majority of the renewable energy consumption in Africa with a large margin. Wind comes second. However, amongst the new green technologies in Africa, Solar power can be regarded as the most promising. This is because Africa has intense sunlight that is evenly distributed all though the year [13] . Another advantage is that solar power does not require a grid. Collier & Venables likened solar power to mobile phones which conquered Africa because the existing landline networks were inadequate [14] . Solar power, however, is both expensive to implement and skill-intensive. The maintenance needed by solar panels requires technicians to be distributed around. Thus the life span of solar panels is reduced and costs increased when these technicians are scarce. [15] . At the current stage, solar power is only realizable for houses and firms that are small in nature with conditions of grave energy shortage and high shadow price of energy. Solar power may be very useful in making power available to outlying villages but not very much for urban areas. Solar also requires storage if it is to serve all through the day. Storage cost for solar power system is high.

Solar energy however is continually making steady progress in the continent. Aderemi, et al. [16] explored the implementation of solar energy for supplying power to mobile cellular base stations in South Africa. They believe that the proposed approach would greatly contribute to the eradication of harmful gas emissions, improve power supply, while also minimizing energy cost. Thus, they provide an insight into the ability of South Africa to transition to Solar PV Powered Base Station from the conventional Base Station. Through the study, they suggest investments towards the development of Solar PV Powered BS rather than other power sources to enhance cellular network operations.

The presence of many high-altitude 1 areas in Africa presents a great advantage for hydropower as the water vapor from the Atlantic falls comes around it. Many of the renewable projects in Africa are hydro and of all of them, Hydro is presently the most promising for large-scale development [17] . The capital costs per MWh of Hydro power are the cheapest among the renewable energy sources.

Another advantage Africa can utilize is her large landmass. The population density of sub-Saharan Africa is low and thus much of the land mass is idle [18] . Azouma, et al. [4] introduce the production of biogas with the aid of agricultural waste for sustainable supply of energy in developing countries (in this case, the Republic of Togo). They investigated the conversion of solid wastes from pineapple into biogas through anaerobic digestion carried out in a laboratory. From the experiments carried out, it was deduced that the pineapple waste was highly compliant for producing biogas. A high percentage of methane content (41.0 vol. % - 70.5 vol. %) was derived from the conversion, thus resulting in a successful implementation, as the goal of obtaining high methane yield was achieved. As future work, they plan to construct a pilot plant and employ the laboratory results for sealed biogas production. Amigun, et al. [19] also present an outlook towards biofuel development in Africa as well as the environmental, social and economic issues prevalent in the countries. In their work, they propose the combination of policy incentives with advanced technologies in order to reduce hazards caused by biofuels production and as a result, contributing to sustainable development. They recommend gender equity for sustainable biofuels assessments and urge governments to develop regulations, programs and policies regarding biofuels development.

Uduma and Arciszewski [20] recommend solar and biomass-based sustainable energy systems for solving problems of water shortages and utility challenges in rural and urban environments in Nigeria. They propose the adoption of these two Renewable Energy Technologies (RETs) for sustainable energy development. They also specify various strategies in which sustainable energy sources can be developed including NGO partnerships, creative lending strategies, shifting energy-distribution and renewable energy business incubators. The authors believe that the implementation of sustainable energy would result in stability (political stability and social order) in Nigeria, while stimulating economic development and curbing social vices.

Gebretsadik, et al. [7] propose a model for maximizing generation of wind and hydropower. This model was applied on the hydropower system and reservoir storages located in the Zambezi river basin. The outcome of the experimentation depicted a reasonable increase in the wind penetration level in South Africa’s power system and a decrease in utilization of coal power. With these results, the authors believe that developing this model would play a great role in South Africa’s goal by reducing the emission of greenhouse gases.

Kuang, et al. [8] review the utilization of renewable energy for power generation in Islands. They were able to identify wind energy, solar power and hydropower as the major sources of electricity in most islands, while the remaining few generated electricity from geo-thermal, ocean energy and modern biomass. They also brought an insight into the percentage of electricity produced by these islands, with 100% generated from renewable energy in some islands and 10% in some others. They identified major barriers of the utilization of renewable energy in the islands including randomness and variability of renewable sources dependent on weather. The authors encourage the inculcation of advanced information and communication structures in smart grids for efficiently conserving energy in islands.

Hassan, et al. [9] provide a survey of already existing works and required principles needed for enhancing understanding based on the implementation of renewable energy in mobile cellular networks. In addition, they propose a reference model for Renewable Energy Base Stations (REBS) while completely analyzing its components. This model was evaluated with several performance metrics, which include; economical, environmental, technical, feasibility, and quality and energy metrics. They derived positive results, ensuring promising advancements when considering future developments. As future work, the authors plan to carry out investigations on the integration of REBS to the power grid system.

Like wind and solar, most renewable systems have low energy content, sitting problems as well as capacity factors thus needing significant inputs of conventional fuels to maintain stability of supply [20] . Different fuel types need different amounts of space, and renewable energies generally need more space than fossil fuels. One way to compare them is to use the concept of power density, measured in watt/m² defined as the average electrical power produced in one horizontal square meter of infrastructure. In terms of scale, wind and solar for instance have a far lower energy content than conventional energy. While conventional sources have 85% to 90% capacity factors, wind and solar have between 21.7% and 34.4% meaning they will not supply 65.6% - 78.3% of the time in a year [21] . Also, wind has a power density of 1 watt/m² which is low in comparison to coal and gas-fired generation which have a power density of 550 W/m² and 1100 W/m² respectively. 300,000 km² of land would be used in order to reach Africa’s 300 GW potential with maximum power factor. This is the same as half of Eastern Africa. This may be bound to experience delays as it would require huge capital investment in land leading to social acceptability issues. Solar on the other hand has a power density of 6.5 W/m² and only converts 20% - 30% to electricity [20] .

Apart from the natural assets, Africa also needs other inputs. Capital endowment (physical capital, human capitals and skills) is a great need as Africa has a low savings rates and poorly developed financial markets [21] . Governance endowment, which involves the institutional capacity towards the implementation and regulation of economic activities, are an important part of the energy sector’s growth. Africa greatly lacks capacity in this area and there are politically economy obstacles that preclude the making of some policies.

In terms of economics, renewable energy sources do not incur fuel cost. Two things, however, challenge its competitiveness: high capital cost and value of generation. It can be shown that we do not always derive the same electricity value at all times. Power at peak demand has more value than off peak generation. For instance, in wind energy, wind velocities blow well at night and are inversely related to the daily hours of peak demand. Also, renewable energy sources are not always available at periods when they can be most economical. This makes dispatching or scheduling not possible and thus the need for backup capacity becomes essential for system reliability [20] . The backup capacity then adds to the costs of the renewable energy source and increases the operation costs of the system. Energy production, especially in relation to green energy, requires capital, high skilled labor as well as regulatory and governance capacity [21] .

Azimoh, et al. [12] evaluate the financial barriers hindering implementation of renewable energy technology in Sub-Saharan Africa, regardless of the declining cost of RETs. They view this reduction in cost as an avenue for increasing access to electricity in the region. However, they have been able to point out several factors inhibiting the development of RETs despite the price reduction. The following factors are presented as the barriers towards RET development: lack of renewable energy policy, existence of weak institutions, lack of skills for the operation and management of off-grid electrification in the region. They observed that the two phase; capital and operational expenditure phases are points where the most failed projects occur. Therefore, more research is required to address these challenges. Pegels [10] and Sebitosi and Pillay [11] in their works, identified the potentials and barriers for renewable energy in Southern Africa, while providing policy recommendations. They were able to recognize the major barriers involved in implementing the system, which comprised two investment-planning factors: risk structures and cost.

Pegels [10] and Sebitosi, Pillay et al. [11] in their works, identified the potentials and barriers for renewable energy in Southern Africa, while providing policy recommendations. They were able to recognize the major barriers involved in implementing the system, which comprised two investment-planning factors: risk structures and cost.

In terms of sitting, traditional power plants can be easily placed anywhere. The required fuels can be transported to the generation utility. Renewables such as wind or solar must be located at certain places (where the wind blows or sun shines). This means we have a limited number of optimal sites and as the ones with the lowest costs get utilized first, there results an increase in the successive costs of utilizing these sites.

In [13] the authors analyzed the energy situation in the African Island states and recommend the use of renewable energy to improve such situations. However they discovered that some of these countries possessed barriers for access to energy including lack of political commitment, poor investment in energy sector and technical hindrances.

Collier & Venables, argued that Africa’s need to address its energy shortage is a priority and can be helped by creating much of her energy production on energy resources (oil, gas, coal) that she is endowed with [21] . (Wesseh and Lin, 2016) claimed that Africa would have a higher chance of reducing the effects of climate change if they make use of stable production recipe (like fossil) to accelerate wealth creation [20] . They argued that Africa should prioritize ending energy poverty and boosting real GDP while making environmental concerns on the long run; protection of the environment shouldn’t be at the expense of growth [20] . There is therefore the challenge of depending on renewable energy in the process of industrialization and urbanization. China for example used its cheap energy resources such as coal to alleviate poverty and achieve close to 100% electrification rate. They are now making progress towards renewable energy but this is after eradicating poverty and reaching a certain economic growth level [20] .

For renewable and green energy to develop in the continent, various participations are required from different sects of the nations in Africa. The key participants and the corresponding actions required are identified:

Renewable green energy has one major distinction; it has a very positive effect on the environment. Table below shows the “Intended nationality determined contributions” (INDC) commitments made by African countries. These show or reflect the plans that the countries propose and plan to execute concerning climate change actions.

GHG = Green house gas; MCT = Mitigation contribution type; GTT = Greenhouse gas target type; BST = Baseline scenario target; BYT = Base year target; GHGT = Green house gas target; NGHGT = Non green house gas target; NA = Not applicable; A = actions.

Energy drives all socio-economic activities and in it lies the battle for Africa’s long term development and economic prosperity [20] . The increase in the number of policy makers talking and strategizing around renewable energy technologies would provide a sustainable growth path that is cost-effective for Africa [25] . This paper demonstrated the impact of renewable energy to the sustainable development of Africa. Renewable energy is increasingly promising in Africa and has received a lot of spotlights over the years. While most renewable energy sources are more expensive to implement than non-renewable energy sources, it is expected that renewable energy sources would become increasingly cost-effective with more technological advances. While the world drives green energy, some researchers claim that Africa should temporarily put a delay on environmental concerns and prioritize solving their energy shortage with cheaper non-renewable sources [20] . Some researchers advocated for a mix of both sources, Müller-Steinhagen and Nitsch [19] proposed the use of renewable energies for sustainable development. They suggest the combination of renewable energy with conventional energy carriers, which would lead to the achievement of the necessary sustainability criteria. They believe that the conventional methods of energy conversion for electricity supply (i.e., heat and chemical energies) would be able to supply reliable energy at reduced costs, when adequate technological development is employed. To achieve such development, they suggested the acceleration of the growth rate for timely achievement of energy goals.

The authors declare no conflicts of interest regarding the publication of this paper.

Nkordeh, N., Ejiro, M., Okeoghene, M., Awomoyi, M. and Bobmanuel, I. (2023) Renewable and Green Energy, Africa’s Pathway to Sustainable Development; Harnessing the Continent’s Natural Energy Sources. Smart Grid and Renewable Energy, 14, 131-151. https://doi.org/10.4236/sgre.2023.147008