In sub-Saharan Africa, about 600 million people lack access to electricity. For example, in Nigeria, about 44 per cent of the population are unconnected, and supply is often inconsistent and unstable for those who are. Though the available generation capacity is 12,340MW, the daily average distribution hovers below 5,000MW. In addition, grid inefficiency and gas supply challenges stifle current generation capacity. As a result of these challenges, providing electricity access via circumventing the grid has become more feasible in many places.
The recent proliferation of renewable energy solutions has made solar solutions the preferred choice for off-grid electrification. However, while solar may be ideal for many sub-Saharan African nations, especially since high solar irradiation and fossil fuel costs are high, for other countries with fossil fuel resources like gas, one expects it to factor into off-grid electrification approaches.
While gas has been given ample consideration in on-grid electricity generation, it is often not considered for off-grid electrification. The large investments needed to construct gas transport infrastructure to off-grid areas, often far from the gas exploration centres, has made gas-powered off-grid sources largely unappealing. But this might be changing.
Compressed Natural Gas
The need for cleaner energy generation sources and the global increase in gas reserves (natural gas reserves have grown by about 40 per cent in the past 20 years) have paved the way for increased gas-to-power development over the past decade. While gas usage has prominently been for grid-connected power generation, off-grid usage has grown recently, especially among small manufacturing industries and information centres.
With the advent of virtual pipelines, compressed natural gas (CNG) has increasingly been adopted as an alternative energy source for distributed energy systems. Virtual pipelines consist of specialised vehicles that transport pressurised natural gas. CNG transport leverages existing transport systems – either roadways or railways – and has made gas transport possible across terrains where pipeline constructions are impossible.
Potentials for Nigeria
Considering Nigeria has the 9th largest gas reserves globally, incorporating CNG generation in its off-grid electrification plan would greatly boost the domestic gas industry and electricity access. Renewable sources like solar are not resilient; they are affected by climatic conditions and rely on battery storage systems or diesel generators as backup options. Battery-tied energy systems are largely expensive, reflecting off-grid energy costs often unaffordable by rural communities.
CNG off-grid solutions could present a cheaper and reliable off-grid option, especially for industrial and economic clusters. Natural-gas generators could also be coupled with renewable sources (replacing diesel generators), providing cleaner hybrid systems with fewer emissions.
While the transition to clean energy would occur in the long term, natural gas could serve as an intermediary cleaner option for power generation. The IEA predicts that Africa’s natural gas consumption would increase to 11.1 Trillion Cubic Feets (TCf) in 2040. In 20 years, it is also expected that Africa’s natural gas use for electricity generation would increase by as much as 85 per cent.
Now is the best time for gas-rich African nations to position themselves for increased natural gas utilisation. The integration of CNG in off-grid electrification would increase energy security and benefit the domestic natural gas industry and economy.