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8/12/2019 Africa Yearns for Electricity 2012 - Article by Jacob Klimstra
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Africa yearns for electricity
Author:
Jacob Klimstra
Senior Energy and Engine Consultant
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Introduction:
electricity use and the economy are related
Figure 1: The relationship between electricity use and gross domestic product in the
world (data IEA)
When comparing electricity use and the economy in different regions in the world,one will notice a strong the relationship between the two. Figure 1 gives the grossdomestic product (GDP) in Purchasing Power Parity per person per year as afunction of per capita electricity use for the major areas of the world. The redtrend line in figure 1 has a high correlation coefficient of 0.95, meaning a close tolinear relationship between GDP and electricity use. The slight deviations from thistrend line can be easily explained by e.g. on the one hand energy wastefulnessin the USA and in the oil states in the Middle East and on the other a morepreservative attitude in Europe. Also the local climate plays a role. In economicallydeveloped countries, about one third of total electricity use is end consumptionin households. Two thirds of electricity supply is used in industry and by services
for wealth creation. Use of electricity drastically increases productivity per person.Africa as a continent scores lowest in electricity use per capita as well as in GDPper capita. Consequently, in order to become globally competitive and to abolishpoverty, Africa needs substantially more electric energy.
The average electricity consumption per person per year on the African continentis about 500 kWh. That is only 20% of the world average of 2500 kWh. Yet, eventhis low electricity consumption is not representative for the majority of Africans. Ifelectricity use in the North of Africa and the Republic of South Africa is subtractedfrom Africa total, a very low 180 kWh per capita per year results for East, Centraland West Africa (Figure 2). This means that some 80% of African people use lesselectricity than 7 % of the world average. This equals a meagre 1.5% of what the
average North American citizen uses. A large fraction of the African population isnot even connected to an electricity grid at all.
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Figure 2: The differences in electricity use per person on the African continent.
A few things are obvious now:
z Africa is not Africa total. Electricity use per capita in the countries in the Northof Africa as well as in the Republic of South Africa is much higher than in themajority of countries in Africa.
z Raising the productivity and living standards for Africa in total to a globalcompetitive level requires at least a fifefold increase in average electricity supplyper capita.
z For the bulk of the African population, at least a ten to twentyfold increase inaverage power supply is needed in order to warrant reasonable living conditions
and economic competitiveness with the rest of the world.
It should be noted that for a more comfortable life in homes and communities,a residential electricity supply of 500 kWh per person per year might suffice.However, much more electricity is needed to boost economic productivity withmodern industries and services. Treatment and chilling of valuable agriculturalproducts, powering mining activities, manufacturing, data handling andcommunication are only possible with ample electricity supply.
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Example Ethiopia
Figure 3: The positive trend in electricity use per capita in Ethiopia (data IEA)
Ethiopia is a country with a positive trend in electricity supply. Yet, the currentper capita electricity supply at a level of 50 kWh per year is amongst the lowestin the world. Fortunately, electricity production in the country is growing rapidlywith some 7% per year. This is already quite an achievement. However, forreasons of economic competitiveness, average electricity use per capita inthe country should be increased from the current 50 kWh per year to at least amodest 1000 kWh per year. If this will be done in say 15 years, the annual increaseshould be around 22%. Even with such a high growth rate, the per person power
supply in Ethiopia will ultimately still be less than 1/3 of the world average. Manyscenarios indicate that global electricity use is expected to double in 20 yearstime, so the average value goes up.
Figure 4: The growth trend of electricity use in Ethiopia in a global perspective
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The question is how Ethiopia can rapidly produce more electricity and distributeit to the population. The country needs the capital for the investments as well assufficient primary energy for the power plants.
EEPCO, the national electricity company of Ethiopia, has prepared plans which arefully in line with the previous analysis. The country is increasing electricity exportsto neighbouring countries Kenya, Djibouti, Sudan and South Sudan, in orderto generate income for further investments in the power sector. Loans from the
World Bank and the African Development Bank of 1.3 billion US$ are used to buildsubstantially more hydro capacity (Blue Nile 6000 MW, Gibe III 1870 MW) as wellas wind farms and geothermal generators. Ethiopia has the highest potential forhydropower in Africa. Plans are to add 37 GW of renewable generating capacityin a 25 years time span. To provide the 85 million inhabitants with 1000 kWh ofelectricity per person per year, one needs 20 GW generating capacity runningat a capacity factor of 50%. The extra generating capacity can be used as asustainable source of money from electricity exports.
The EEPCO plans are great and exactly what the country needs. However, plansare always accompanied by complicating factors. To mention a few:
z Ethiopia has a population growth of 3% per year, which accelerates demand;z A loan of 1.3 billion US$ for 8 GW capacity equals already some 4% ofEthiopian GDP;
z High dependence on hydro can be risky with aberrations in annual rainfall.
Nevertheless, the planned increase in power production is crucial for lifting theEthiopian economy up to a competitive and sustainable level. Ethiopia is blessedwith so many renewable resources. For an economic hydropower potential of160 TWh per year, an annual electricity production of 2000 kWh per capita ispossible. If 1000 kWh per capita is enough in a sustainable society with a goodclimate, the country can export 80 TWh per year. For an electricity export price
of 10 US$cts/kWh, that yields 8 billion US$ per year. On the long run, this offersgreat expectations for Ethiopia.
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ENERGY SOURCES FORELECTRICITY PRODUCTION IN AFRICA
Figure 5: Hydropower use and potential in Africa.
Many other African countries do not have such natural resources as Ethiopia andtherefore still depend on fuel for electricity generation. For Africa total, 40% ofelectricity is produced by coal, 30% by natural gas, 15% by hydro and 12% byoil. The contribution from bio fuels, wind and solar based energy to electricityproduction is negligible.
Figure 6: African electricity production according to source (year 2009, data IEA)
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Figure 6, which gives the energy sources for electricity production in Africa total,is again not representative for the bulk of African countries. Figure 7 shows thatthe Republic of South Africa is responsible for almost all of the coal applications,while North Africa is generating its electricity primarily with gas and oil. Hydropower is the major electricity source for the large remaining part of Africa. Thebar in figure 7 indicating the energy sources for electricity for the energy-deprivedgroup of 780 million people is fully dominated by it. Much hydro power is basedon run of the river systems that show a high volatility in output depending upon
rainfall. Reservoir-based systems have a much better ability for dispatching poweraccording to demand.
Figure 7: The large differences in primary energy type for power production sources
between the African areas
Since most countries are not blessed with the natural resources that e.g. Ethiopiahas, other solutions have to be found to increase electricity production. A simplesolution could be to build a transmission and distribution system for natural gasthroughout Africa and use gas from the large reserves Nigeria and North Africaas a fuel for power plants. However, most African countries cannot yet afford theprice for the gas that Europe and Asia are willing to pay. Therefore, the gas doesnot go to East, Central and West Africa. Using the huge coal resources in Africa isanother option but that creates conflicts with aspirations to reduce carbon dioxideemissions in the world.
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Figure 8: Major natural gas reserves in Africa (T = tera = 1012; G = giga = 109) (data:
The World Factbook, IEA and BP)
Example Nigeria
Nigeria is in a favourable position to have natural gas for supplying its economywith electricity. At the moment, the countrys GDP (PPP) of 1190 US$ per capitaper year and its electricity use of 120 kWh per capita per year are still in the samelow range as that in e.g. Ethiopia. Exploiting the 7 Tm3conventional gas reservesin Nigeria of over a time span of 50 years means that 140 Gm 3per year can beused. This situation can be compared with that in the Netherlands, where a gasfield of approximately 2.8 Tm3has been producing between 60 and 90 Gm3peryear during a time span of 35 years. About half of that was exported by pipelinesto neighbouring countries. If Nigeria would use 50 Gm3gas per year for electricityproduction, it would yield some 250 TWh per year, or some 1600 kWh per capitaper year. That would fully change the economy and the living standards in thecountry. The rest of the potential gas production, some 90 Gm3per year, canbe used for exports. The country exports already 25 Gm3per year as LNG. Theunconventional gas resources in Nigeria are estimated to cover another 7 Tm3.
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Figure 9: Sub-Saharan natural gas reserves excluding Nigeria
Natural gas reserves in Africa excluding Nigeria and North Africa are limited(see figure 9 and compare with figure 8). South Africa seems to have promisingresources of shale gas and coal-bed methane. Yet, some countries, such asAngola, Cameroon, Mozambique and Namibia have interesting gas reserves thatmight be used intelligently for enhancing electricity production. Burning that gasin large base-load power stations is not wise. The technical life of a large powerstation is at least 30 years. As an example, the 100 billion m3of natural gas ofNamibia can fuel a 2000 MW base load power plant for 30 years, but then allthe gas is gone. It is much wiser to use the gas with flexible power stations asa back-up battery for intermittent renewable sources (long-term battery). In the
more distant future, say around the year 2050, a large proportion of renewableelectricity sources will dominate power production. One can already notice earlydevelopments of this in Germany and Denmark. Africa will not be an exception.The costs of solar PV panels are rapidly decreasing and the African continent isblessed with much sunshine.
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A STRATEGY FOR INCREASINGELECTRICTY SUPPLY IN AFRICA
Africa has a great potential for renewable energy, especially for solar PV systems,hydro power and geothermal sources. It is the chicken and egg syndrome thathampers a quick implementation: the continent cannot earn the capital requiredfor power production equipment because of its low productivity resulting from alack of electric energy. Therefore, as much as possible external support for thecontinent must be directed towards providing the economy with electric power. Inaddition, much of the proceedings from the African boom in selling minerals to therest of the world should be used for enhancing electricity production.
Investing in power plants in Africa can even be quite lucrative. There is muchsuppressed demand for electricity which means that newly build power capacitywill quickly find its customers. Many potential customers use small generatorsfuelled by petrol or diesel oil, which is less economic than electricity produced byan efficient power plant. Household members that spend hours per day in findingfuel for cooking would be happy to use efficient electric cookers.
In defining a proper strategy for a rapid electrification of Africa, one has to takeinto account some characteristic boundary conditions:
z The existing low density of electricity use;
z Limited transmission and distribution networks;
z Low availability of local capital;
z Local manpower input preferred for enhancing employment;
z Local maintenance + repairs preferred;
z Substantial natural gas reserves only in North Africa and Nigeria;
z
Natural gas as back-up reserves in more countries;z Large potential for hydro power in some countries;
z Large potential for geothermal power and solar PV in many countries.
Approach:
z Install quality generating equipment with a relatively low price (such as gas-firedmodular generating units);
z Install generating equipment that can compensate for intermittent renewables(flexibility);
z Create political stability for long-term Power Purchase Agreements;
z Avoid excessive red tape;
z Avoid excessively stringent emission regulations that may apply for a metropolisin the rich world;
z Provide excellent reliability with multiple units in parallel;
z Avoid the trap of installing only single large generating units.
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The solution
Although Africa is still hesitant to implement solar PV (currently only 0.004% ofelectricity generated) because of the investment costs, its costs will soon becompetitive. Batteries for storage to cover electricity demand when the sun doesnot shine are still prohibitively expensive, but expectations are that in some 20years time affordable batteries have been developed. As a medium term solution,new flexible power stations that will run on natural gas or even heavy fuel oil
should therefore be installed for coping with the variability in demand and fortheir ability to compensate the variations in output of renewable energy sources.The experience in Germany, a country with relatively little sunshine, is alreadythat solar and wind based generators drastically reduce the need for fuel-basedgeneration on sunny and windy days. In Africa, fast backup systems will beneeded during a few hours after sunset and at times with low rainfall. The back-upsystems will need to have a very high ramp rate to cope with the rapid decline insolar PV output just before sunset (figures 10, 11).
Figure 10: High ramp rates needed for back-up generators for PV at sunset
Figure 11: Comparison of the response rate to power demand of some generating
systems.
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The backup power plants of the future have to run considerably less hours peryear than the traditional power plants in the past. Coal-fired and especially nuclearpower plants are way too expensive to run limited hours and are not suitable toexperience many starts and stops. The relatively low investment costs of gas andoil fuelled power plants result in low capital costs per kWh, even when runninglimited hours (figure 12).
Figure 12: Effect of a reduced utilisation factor on capital costs per kWh
In case of much variability in power demand, generating systems with multipleunits in parallel offer many advantages. Individual units can be switched off whentheir output is not needed instead of running at low load with low efficiency andhigh specific maintenance costs. This cascading way of operation is a keyfeature of SMART POWER GENERATION.
Figure 13: The high overall fuel efficiency of a cascading power plant
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Modern economies depend heavily on a reliable power supply. Black outs andbrown outs hamper productivity and reduce product quality. Using the multiplegenerating units concept for power plants with an n+ 2 approach providesexcellent reliability of power supply. This is especially the case in Africa, wheretransmission grids are often weak or even lacking. This high reliability can neverbe achieved with single big power plants. A reliability of 99% per generating unitis a practical technical standard for an individual generating unit. A system with6 generators in parallel where 5 are able to carry the load (n+1) is already able to
create an electricity supply reliability of 99.85%. One extra unit (n+2) can serveas reserve capacity when one of the others is undergoing maintenance. In theoppostite case with just a few large generators supplying to the grid, tripping ofone unit will have too much impact on the grid and can easily cause a black out.
Figure 14: Supply unavailability of a power plant based on multiple units.
The principle of power plants consisting of multiple units in parallel can be veryadvantegeous in e.g. Nigeria. A widespread gas-based power generating systemthere needs much flexibility, especialy in the beginning. Gradual increases inpower demand can be easily met by installing an extra identical generatingunit. It is foreseen that even in Nigeria much solar PV will be installed resultingin high ramping rates for fuel-based generating equipment just before sunset.Such an approach might preserve much of the precious hydrocarbon resourceas feedstock which can act as a battery for the future. Having ample access to
electricity will lift the country permanently out of poverty.
0.144089402
0.001940598
1.47015E-05
5.94E-08
1E-10
99.85395524
1E-11
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IN CONCLUSION
Removing poverty, famine, instability and conflicts in Africa requires a substantialincrease in electricity generation for the continent. The current average 200 kWhper capita per year in East, Central and West Africa has to be raised rapidly toat least 1000 kWh, with a further expansion on the longer term to 2500 kWh.Ultimately, electricty production has to be based on sustainable resources, asis the case in the rest of the world. However, to pull the continent out of theviscious circle of incompetitiveness caused by lack of electric power, a smartsystem based on flexible power plants running on fuel is needed. Such generatingsystems quickly provide the population with the required power while it caneventually serve as a back-up system for renewable energy sources.
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