Edited by Sharyn Macnamara

Nigeria is the largest and one of the fastest growing economies in Africa , yet despite a wealth of natural resources , the country continues to struggle with acute electricity shortages , which constrain its economic development . To combat this , last year the Nigerian government formally launched “ the Decade of Gas ,” setting gas development and utilisation as a national priority .

The company ' s 2022 to 2040 Analysis of Nigeria ’ s National Power System used the advanced Plexos modelling tool to quantify system level benefits of different technologies in the Nigerian power system . The model was used to analyse and identify the optimal capacity expansion for the country and showed that the country requires more aggressive capacity additions than the current situations , referred to as business-as-usual scenarios , to achieve the country ’ s stated 30-30-30 vision . This vision expresses the Nigeria government ’ s target to add 30GW of power generation capacity , with 30 % coming from renewable sources by 2030 .

But looking beyond 2030 , and by mapping the country ’ s solar and wind potential for renewable energy , together with transmission data from five major regions , an advanced 30-30-30 scenario can be envisaged which would generate additional power and significant cost savings .

This advanced scenario recommends the installation of 45GW of lowcost renewables in the north and west of the country by 2040 , while concentrating 43GW of gas-fired internal combustion engine ( ICE ) power plants in the southern regions with access to low-cost locally sourced gas . Strengthening the transmission capacity between north and south will greatly benefit the central regions as well .

In this context , ICE power plants become the technology of choice because they are flexible by design . They have a high operating efficiency , even at partial load , and are made to cope with regular start and stops . On the other hand , combined cycle gas turbines ( CCGT ) lack the flexibility to match the fluctuations in electricity demand . They rely on a consistent and pressurised gas supply and are most efficient when operated close to full capacity . They are not suited to offset the intermittent supply of renewables .

Detailed technology comparison between CCGT and ICE power plants show that for an equivalent 350MW plant running 8 000 hours per year , the company ’ s solution saves between USD11-17-million per year compared to the CCGT solution , thanks to its better performance in hot climates , better part-load efficiency and lower investment cost .

ICE power plants also offer several other advantages relevant in Nigeria . Their modular design allows for easy to construction – fully scalable , they can be deployed in phases . They can be ramped-up or down quickly to adjust to demand and provide a great hedge against fuel supply risk , as its engines can be operated on natural gas , Diesel , HFO or biofuels . They require little water to operate with a water consumption of less than 1 % compared to the CCGT technology .

Small , inefficient , expensive , and polluting diesel generators are widely used in Nigeria at present to compensate for weaknesses in the country ’ s grid capacity , and despite recent improvements , the gas supply system is not fully stable , which places additional strain on the country ’ s still fragile electricity network .

The company is convinced that building flexibility into the system by investing in gas engine power plants will provide a stable and reliable long-term solution to Nigeria ’ s energy challenges . •

As more capacity is added to the system , the cost of electricity is predicted to fall drastically within the first years , as locally sourced gas fuels more cost-efficient gas power generation to overtake expensive diesel . With the advanced scenario , cumulative saving to 2040 of up to USD430-billion can be achieved when compared to the businessas-usual scenario .

ICE power plants offer flexibility For Wärtsilä Energy , the choice of power generation technology is as important as the choice of fuel . In a system that maximises the use of low-cost renewables , being able to rely on flexible power technologies becomes paramount .

Impression Africa Power projects Wartsila .

Wärtsilä Energy