Electricity is necessary for the economic development of any community. However, electricity supply becomes a challenge for remote and isolated communities [16
]. Renewable hybrid energy systems may safely generate electricity for minimum demand requirements without implementing large facilities or networks. Throughout this case study the integration of Renewable Hybrid Systems in the national energy context is studied as a strategy for increasing sustainable electrification in isolated areas and the possibilities of green entrepreneurship.
3.1. Energy Context of DRC
Democratic Republic of Congo (DRC) is located in the centre of Africa, near the equator. It is the second largest country in Africa in terms of area (2,345,441 km2) with an estimated population of 74.88 million of inhabitants, having a population growth rate of 3.1% from 1990 to 2014. Approximately 75% of the total population lives in rural areas and it is dependent on agriculture, land cultivation and forestry being their major economic activities.
In terms of energy, DRC has a great potential with abundant and varied energy resources: biomass, solar, wind, hydraulic energy, hydrocarbons, including methane gas from Lake Kivu, mineral coal, oil shale, and so on. The sustainable development of these energy resources for economic and social development of the country will certainly be the main agenda of the national and regional Governments.
DRC’s energy sector is currently centralised and characterised by a state monopoly. However, it has a high energy potential for distributed energy supply over the country’s territory, which is almost unexploited. Estimations of DRC’s energy potential are around 100 GW of exploitable capacity, of which almost half (44 GW) is concentrated at the river Inga. Despite this extraordinary energy potential, especially for renewable energy generation (mainly hydro based), DRC’s national electrification rate is 9% with strong disparities between urban and rural areas (Kinshasa is 44%, while rural Bandundu is 0.6%) [17
]. Moreover, the transport and distribution electricity network is out of date and unable to support actual current consumption, which results in frequent power outages. In the places where electricity is essential, such as hospitals, hotels, public buildings, and so on, the problem is circumvented by using fossil fuel generators to get some security in electricity supply. However, many remote areas exist where grid extension is costly and these areas simply do not have access to electricity [17
]. In these cases, renewable hybrid systems may be the best alternative to provide energy access and economic development to the societies, without large initial investment in network extension. The DRC energy policy to increase the electrification rate was implemented by means of the Electricity Code in 2014, which authorized the establishment of a regulatory agency and a rural electrification agency, while promoting the power sector to private investment [19
represents the energy flow diagram of DRC in the year 2014, including the origin (energy source) and destination (sector) of energy units. As may be observed, only oil and renewable energies are supplying the country. Country imports are oil products for transport and electricity; while hydro is all for electricity generation and biomass is mainly used in residential contexts as fuel.
Data from 2014, provided by International Energy Agency (IEA) [19
], represented in the following Energy diagram for DRC (Figure 2
), shows a national energy supply of 30.04 Mtep (Million tons of oil equivalent, 1 Mtep is equivalent to 11,630 GWh) in contrast to 28.79 Mtep in 2013, mainly based in three energy sources: oil, biomass and hydro. Produced oil is exported to other countries (1.07 Mtep), while oil products such as gasoline and diesel are imported in large quantities (1.78 Mtep), so DRC presents an oil product dependency from the exterior, mainly in transport (1094 Mtep). Biomass is the highest energy supply in the country, and it is based on traditional fuels such as firewood, charcoal and waste, which denotes the reduced access to energy supply and the low level of electrification in the country. Hydro is the only source for electricity generation together with minor contributions from coal and natural gas.
Total final energy consumption reached 21.51 Mtep, an increase of 12.5% from the previous year (19.11 Mtep in 2013). The sector leading consumption is residential (77%), followed by industry (16%) and transport (7%), while other forms of energy such as electricity contributes with only 4.1%.
3.2. Comparison of Scenarios: BAU vs. HRES
Further to the analysis of the actual energy context, this section compares the evolution of two energy scenarios: BAU and HRES. BAU is based on a continuous trend where participation of each energy source to the national mix is maintained, together with the electricity import-export balance. To do so, a historical analysis has been carried out in order to forecast the growth rates of population, GDP, primary energy and final consumption for each sector (see Table 2
The second scenario, HRES, proposes a sustainable roadmap based on increasing renewable energy in the energy mix of the country by means of implementing HRES. This scenario aims to increase the access to electricity using distributed renewable hybrid technologies and palliating the raise of CO2 emissions introducing biofuels in the transport sector.
The comparison showed the impact of the proposed measures in a series of energy indicators and graphs representing the evolution of both energy alternatives over time. Results of the sustainable energy indicators for BAU and HRES scenarios and their forecasted evolution within the time period of study (from 2014 to 2035) are shown in the following tables (Table 3
and Table 4
The next step is to analyse the key indicators. Figure 3
represents the analysis of the primary energy and CO2
emissions for both scenarios. As may be observed, the HRES scenario shows an increment of total primary energy with respect to BAU. This is due to the increment in distributed electric generation with renewable hybrid systems. CO2
emissions are similar in both scenarios; HRES is slightly lower since this scenario considers a penetration of 10% of biofuels in transport, thus replacing part of the fossil fuel consumption in this sector.
Energy intensity is analysed using three main energy indicators: total primary energy per capita (TEP/capita), average consumption of electricity per capita (electricity/capita), and total primary energy per gross domestic product per employed person (TEP/GDPppp). In this regard, it is observed that HRES increases the electrification rate to 0.58 kWh/capita by 2035, while continuing with the current energy paradigm will quasi maintain electricity rate to actual value (Figure 4
Exterior dependency is similarly reduced in the HRES scenario. Penetration of renewable hybrid systems in remote areas will increase the percentage of population with electricity access without compromising their energy independence, since HRES are off-grid power plants based on local resources (Figure 5
). In the case of continuing with the current scenario (BAU), fossil fuels and electricity dependency will increase in future years.
generation in the HRES scenario would cover a wider range of electricity access in isolated areas, which would also imply higher electricity consumption and economic development of the area. Increasing electricity rate to Africa’s actual values of electricity per capita will require a significant effort and compromise from national and regional government to promote HRES as a local and sustainable alternative for rapid energy development in off-grid areas (Figure 6
consumption per economic sector
indicates a growing energy demand in the residential segment in HRES with respect to BAU, while Industry and Transport show similar energy evolution. The HRES scenario provides an increment in Residential energy consumption originated by the electrification process in residential segment, reaching 50 Mtep in 2035 (Figure 7
Analysis of energy sources
highlights the rapid growth of renewable energies to respond to residential electrical needs in 2035. In both scenarios, production with renewable energies increases significantly, but it is specially significant in HRES, reaching the value of around 4.7 Mtep in 2035 in contrast with 3.3 Mtep in BAU 2035. Oil demand is similar in both scenarios, presenting a value of 6.8 Mtep in BAU 2035 versus 5.8 Mtep in HRES 2035. This difference corresponds to decreasing demand of oil products (gasoline and diesel) in transport that have been replaced with biofuels, increasing biomass requirements in this economic sector (Figure 8
will evolve similarly in both scenarios. Nevertheless, the HRES scenario shows a slight reduction of emissions in transport due to the biofuel penetration in the transport, and an increment in emissions due to the extended used of electricity in the country (Figure 9
As may be observed in the analysis, it is feasible to alleviate energy poverty in the country by means of HRES penetration in remote areas where access to electricity is not available.