TOPIC FIVE: ENERGY

By Prof. Ogoti Robert Maxwell

Definition of Energy –kcse 2021

- Energy is the power/ fuel needed to run a machine/ assist people in production.

Sources of Energy.
 Sun
 Wind
 Fossils
 Plants
 Animals
 Water

Types of energy.
- This refers to the different forms of energy that are derived from the various sources.
- Sources of energy are classified into two types namely;
a) Renewable sources of energy.
b) Non- renewable sources of energy.

1. Renewable Energy Sources.

- A renewable energy source is that source that can be regenerated/ replenished/
reappear/ inexhaustible/ used over a long period of time –kcse 2019
- Renewable sources of energy include; -kcse 2022
 Water
 Wind
 Solar/ sun
 Waves/ tides
 Geothermal steam/ underground steam
 Biomass
 Wood / trees
 Drought animals

i) Solar Energy.
- This is the power from the sun.

Advantages of solar energy –kcse 2012

 It is free.
 It is cheap source of energy.
 It is inexhaustible/ renewable source of energy.
 It is clean/ environmentally friendly.
 It can be stored for future use.
 It is safe to use.
 It can be found everywhere/ it has many uses.
 It is easy to use.

Disadvantages of solar energy –kcse 2017

 Solar panels are expensive to manufacture.
 Low energy production.
 Solar batteries are cumbersome to transport.

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  Solar energy has limited use.
 Solar technology is new hence used by few people.

QUIZ: State three factors that have hindered the development of solar energy in Kenya
–kcse 2023
 Solar energy has low energy output.
 The short life span of storage batteries.
 Competition from alternative sources.
 High cost of purchasing/ installation of solar panels/ low purchasing power of
people.
 Inadequate technology.

ii) Wind Energy.

- This is the power from air in motion (wind).

Advantages of wind energy.

 It is inexhaustible/ renewable.
 It is cheap source of energy.
 It is free.
 It is clean/ environmentally friendly.
 It can be produced on a small scale basis.
 It can be found everywhere/ it has many uses.

Disadvantages of wind energy.

 Not very reliable as the wind may change direction.
 Wind mills are expensive to establish and maintain.
 Low energy production.
 Wind energy has limited use/ cannot run heavy machines.
 Wind mills may take up land needed for agriculture.
 Only available in open areas.

iii) Tidal Energy.

- This is the power from the periodic rise and fall in the level of ocean water due to
gravitational pull by the sun and moon (tides).

Advantages of tidal energy.

 It is inexhaustible/ renewable.
 It is cheap as it is freely available.
 It is clean/ environmentally friendly.

Disadvantages of tidal energy.

 It is expensive to harness tidal energy.
 It is limited to countries with a sea front.
 Low energy production.


iv) Wave Energy.

- This is the power from a moving ridge of ocean water caused by the frictional drag of
wind over the water surfaces. (Waves are oscillation of water particles).

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 Advantages of wave energy.
 It is inexhaustible/ renewable.
 It is cheap as it is freely available.
 It is clean/ environmentally friendly.

Disadvantages of wave energy.

 Power stations are expensive to set up.
 It is not safe in areas with regular incidences of storms, cyclones, hurricanes and
tsunamis.

v) Hydro-electric power.
- This is the energy derived from falling water.
- It is produced by rotating turbines connected to generators.

Advantages of H.E.P.
 It is inexhaustible/ renewable.
 It is clean/ environmentally friendly.
 It can be transmitted over long distances using cables.
 It can be put into many uses e.g. cooking, lighting
 It is relatively easy to use i.e. switching on/ off.
 Dams for HEP creates lakes used for fishing/ irrigation/ recreation.
 It is reliable since significant levels of energy are produced.

Disadvantages of H.E.P.
 Fluctuation of water levels in the reservoirs may lead to shortage of power.
 It requires high capital for investment.
 It cannot be stored once generated.
 Construction of dams may lead to resettlement of people.
 It causes inconvenience to migratory fish species downstream.

vi) Geothermal Energy.

- This is the power derived from steam flowing from earth’s core to the surface.

Advantages of geothermal power as a source of energy –kcse 2015

 It is a clean source of energy/ non pollutant.
 The cost of production is low.
 It has minimal environmental degradation.
 It is a renewable source of energy.
 It is a reliable source of energy.

Disadvantages of geothermal energy.

 Low energy production.
 The sites for exploitation are limited.
 It is expensive to exploit.
 It causes noise pollution.

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 vii) Biomass.
- This is the energy produced from organic matter/ plant and animal waste (Biogas).
- Sources of biomass;
 Wood
 Animal waste
 Agricultural waste
 Molasses produce gasohol

Advantages of biogas.
 It is inexhaustible/ renewable.
 It is cheap as it uses waste products.
 It is readily available in many places.
 Simple technology is used in its production.

Disadvantages of biogas.
 It requires a lot of space.
 It cannot be transported to far places.
 It contributes to pollution which causes global warming.

viii) Wood fuel.

- It is derived from firewood, charcoal and saw dust.

Advantages of wood fuel.

 It is readily available.
 It has no maintenance costs.
 It is a renewable source.

Disadvantages of wood fuel.

 It leads to environmental degradation.
 It pollutes the environment.
 It is bulky/ requires a big storage area.
 It is dirty due to soot and smoke.
 A lot of wood is required because of less energy output.

ix) Draught animals.

- Animals generating power includes oxen/ bulls, horses, camel, donkeys

Advantages.
 They are readily available all over the world.
 It is cheap to maintain animals.
 Animals are flexible i.e. can pass over rugged terrain.
 Some animals can be used in ASALs.
 It is inexhaustible/ renewable.

Disadvantages.
 Animals are prone to diseases and fatigue.
 Their use is restricted only to rural areas.
 They need regular rest as they tire easily.
 They can die as a result of too much work.
 They can only do limited work.

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 2. Non-renewable sources of energy.
- They are sources which are exhaustible if they are not well managed.
- Non-renewable sources of energy include; -kcse 2020
 Petroleum
 Natural gas
 Coal
 Uranium
 Peat

i) Petroleum.
- It consists of gaseous and liquid hydrocarbons from animals and vegetation matter
laid in sedimentary rocks.

Conditions that are necessary for the formation of petroleum –kcse 2022
 Deposition of remains of flora and fauna/fossils/ organic remains over a long
period of time.
 Presence of non-porous rocks underneath the deposits of flora and fauna.
 Deposition of other layers of rocks/ non-porous over the remains of flora and
fauna.
 Compression of the remains of flora and fauna due to folding of the layers of the
rocks.
 Presence of porous rocks in between two non-porous rocks.
 Presence of sedimentary rocks.

By-products of petroleum –kcse 2022

 Lubricants/ Greese
 Tar/ Bitumen/ Asphalt
 Wax/ Paraffin wax
 Sulphur
 Resin/ petro-chemicals

Products from refined petroleum.

 Motor oil
 Diesel
 Liquid and petroleum gas
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  Kerosene
 Gasoline
 Jet fuel
 Lubricants

Advantages of petroleum.
 It is convenient for a variety uses.
 It can be easily transported to far areas.
 It can be stored in tanks.
 It can be used to generate thermal electricity.
 Free of the effects of weather changes.
 Transport and maintenance costs are low.

Disadvantages of petroleum.
 Crude oil is bulky to transport.
 It is non-renewable source of energy.
 It pollutes the environment causing global warming.
 It is expensive for low income groups.
 Exploration of petroleum is very expensive.
 It is highly inflammable and causes fire accidents.

ii) Coal.
- Coal is made up of vegetable matter laid down in a swampy area and buried under
other materials.

Advantages of coal.
 It is most suitable in the smelting of iron and steel.
 It is more efficient in thermal generation of electricity.

Disadvantages of using coal as a form of energy –kcse 2022

 Coal is exhaustible/ non-renewable form of energy.
 Coal is bulky/ costly to transport.
 Soot/ smoke from coal pollutes environment.
 Coal has low calorific value/ low heat/ low energy value.
 Coal excavation lead to degradation of the environment/ pollute land.
 Coal is dirty/ dusty.
 It is expensive to mine/ difficult to mine.
 It is radioactive.

QUIZ: Give three reasons why use of coal as an industrial fuel has declined –kcse 2020
 It is bulky/ costly to transport.
 It is difficult/ expensive to mine.
 It is an exhaustible source of energy.
 It is dirty/ sooty/ dusty/ pollutes environment when used.
 It produces very little energy when burnt/ low calorific value.
 Adoption of new technology in steel production.
 Competition from other efficient sources of energy.
 The deepening of coal mines.

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 iii) Peat.
- It is young coal consisting of partially decomposed organic matter and inorganic
minerals that have accumulated in water-saturated environment.
- It is produced in Russia, Ireland, Finland and USA.

iv) Uranium/Nuclear Energy/atomic energy

- It is derived from the alteration of atomic structures leading to release of heat that
produces steam which is used to generate electricity.
- Nuclear energy is used in USA, Russia, Britain, Germany, France, Japan, South
Africa and Canada.

Advantages.
 It occurs in huge reserves.
 It produces large amounts of energy.
 It has a longer lifetime.
 It is relatively cheap.
 It does not produce greenhouse gases.

Disadvantages.
 It is expensive to construct a nuclear reactor.
 Nuclear wastes are highly radioactive.
 It is exhaustible/ non-renewable.
 It requires heavy capital investment/ expertise.

v) Natural gas.
- It occurs in association with petroleum i.e. normally found on top of upper layers of
crude oil.
- Composed of mixture of hydrocarbons with methane making the highest percentage.

Advantages.
 Clean
 Cheap to transport in pipelines
 Free from weather changes

Disadvantages.
 Accidental fires may occur due to gas leakage/ damaged pipes.
 Pollution of environment through gas leakage.
 Expensive for low income earners.
 It is exhaustible/ non-renewable.

Hydro – electric power (HEP) stations in Kenya.

- River Tana and its seven forks dams produce the highest amount of HEP in Kenya.

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 Physical factors that favoured the development of the seven forks hydro-electric power
projects –kcse 2021
i) Presence of large volume of water from River Tana and its tributaries to
provide water to drive the turbines.
ii) Regular/ constant flow of River Tana which enabled continuous production of
electricity.
iii) Presence of hard basement rock along the site which provided a firm foundation
for the dams.
iv) Availability of enough space for construction of dams/ reservoirs due to low
population in the area.
v) Presence of waterfalls/ rapids/ steep gradient which provided sufficient
hydraulic force to turn the turbines.
vi) Presence of impervious rock which prevents seepage of water underground.
vii) Presence of a gorge/ deep valley which reduced the cost in construction of dam.

Human factors that favoured the development of the seven forks hydro-electric power
projects.
i) Adequate capital for construction and maintenance of HEP projects.
ii) High demand for electricity for industrial and domestic use.
iii) Sparse population in an area to minimize the cost of relocating people.

Benefits of the dams along the river Tana –kcse 2016

i) It provide electric power for both industrial/ domestic use.
ii) The reservoirs provide water for domestic use/ industrial use/ irrigation.
iii) The dams/ reservoirs are tourist attractions earning a country foreign exchange.
iv) The reservoirs are fresh water fisheries promoting fishing.
v) The reservoirs modify local climate.
vi) The dams act as bridges across the river thus promoting road transport.
vii) The dams and reservoirs control floods downstream.

NOTE: Other HEP projects in Kenya include;

 Turkwell Gorge on River Turkwel.
 Sondu – Miriu project on River Sondu.

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 Problems that affect the production of power along river Tana –kcse 2016
 Fluctuations of water levels in the reservoirs leads to the rationing of power.
 Inadequate capital for maintenance/ high cost of dredging/ expansion.
 Siltation of the reservoirs reduces its capacity and makes it expensive to desilt.
 Inadequate skills/ technology in power generation and maintenance of machinery.
 Relocation of people for the construction of dams is expensive.

Hydro – electric power (HEP) stations in Uganda.

- The major power source and HEP project in Uganda is the Owen Falls Dam.
- On the site where River Nile flows out of Lake Victoria provided a natural waterfall
from where the power generation was possible.
- Produces 162MW that supplies most of Uganda’s electricity and about 30MW
exported to Kenya.

Physical factors that have favoured high hydro-electric power production in

Uganda –kcse 2018
 Large volume of water from River Nile/ Lake Victoria to provide water to drive the
turbines.
 The Owen falls/ natural waterfall for power generation.
 High rainfall throughout the year to enable high volume of water.
 Presence of deep valleys/ gorges which reduced the cost in dam construction.
 Presence of impervious/ non-porous rocks that prevent seepage of water
underground.
 Regular supply of water from river Nile/ Lake Victoria which enable continuous
production of electricity.
 Presence of hard basement rocks for firm foundation.

Geothermal Power projects in Kenya.

Places in Kenya where geothermal energy has potential of being harnessed –kcse 2018
 Mt. Longonot/ Suswa
 Lake Bogoria
 Eburru
 Menengai Crater
 Lake Turkana
 Lake Magadi
 Lake Baringo
 Olkaria
 Homa hills
 Mai Mahiu

Reasons why the geothermal power has not been fully exploited in Kenya –kcse 2014
 Inadequate capital required for exploitation.
 There is shortage of skilled personnel as the country relies on expatriates.
 The country faces low level of technology which hinders exploitation of the energy.
 Most of the potential sites are found in remote/ inaccessible areas which makes it
difficult/ expensive.
 Danger of land subsidence as tectonic fluids is withdrawn.

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Ways in which Kenya has benefited from the development of geothermal power. -kcse
2010
 It has provided alternative source of energy.
 It has increased Kenya’s energy output.
 It has helped stabilize the cost of electricity for consumers.
 It has helped in opening up of formely remote areas.
 It has increased employment opportunities.
 It has led to the reduction of importation of hydro-electric power from Uganda/ has
saved foreign exchange.

Factors favouring development of HEP projects in Africa –kcse 2010

i) Presence of hard basement rocks to provide a firm foundation for dam
construction.
ii) Presence of steep rivers/ waterfalls/ rapids to provide a massive hydraulic force
head for power generation.
iii) Regular/ large volume of water from rivers Nile/ Tana to ensure continuous
power generation.
iv) Presence of non-porous rocks to prevent water loss/seepage underground.
v) Presence of a deep narrow valley/gorge to provide a large reservoir behind the
dam/reduce cost of building embankments.

Reasons why HEP projects in Africa are not fully developed.

i) Inadequate capital to develop and maintain HEP projects.
ii) Remoteness of some potential areas limits their exploitation.
iii) Low industrial development hence low demand for electricity limiting HEP
production.
iv) Fluctuation of river regime affecting power production.
v) Limited research is carried out slowing the development of HEP projects.
vi) Foreign aid sought by many countries to put up the projects carries higher
interest rates thereby over-burdening countries with HEP potential.

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 Significance of Energy.
i) Energy is used for domestic purposes e.g. cooking/ lighting/ heating
ii) Energy is used in industrial sector e.g. to run the machines/ lighting/ heating.
iii) Energy is used in transportation e.g. diesel and petrol used in Motor vehicles.
iv) Energy is used in agriculture by powered tractors/ drying grains.
v) Energy is used in water supply where wind mills/ solar power/ diesel engines are
used to pump water.
vi) Energy is used for medical purposes by diagnosing equipment like X-Ray uses
electricity.

Energy Crisis –kcse 2022

- Energy crisis refers to a situation where the prices of fossil fuel rise sharply as a
result of short supply relative to demand.

Causes of Energy Crisis –kcse 2014

i) There is a high demand for oil/ over reliance on petroleum leading to increase in
the oil prices.
ii) There are embargoes/ controls on oil production by the producing countries.
iii) There is de-regulation of oil prices by the suppliers.
iv) There is unequal natural pattern of crude oil occurrence.
v) There is political instability/ wars in some of the oil producing countries.
vi) Inadequate alternative sources of energy leading to over-reliance on oil and oil
products.
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 vii) Improvement in technology resulting into many machines that consume a lot of
energy leading to shortage causing a crisis.
viii) Prolonged drought lowers production of HEP leading to more demand of oil.
ix) Artificial shortages may be created by the oil-producing countries with holding
the oil.
x) Rapid depletion of oil reserves leading to oil shortage hence energy crisis.

Effects of Energy Crisis in Kenya –kcse 2021/ 2022

i) Increase in oil prices triggers increase in prices of commodities/ inflation leading
to low standards of living/ high cost of living.
ii) Increase in oil prices leads to rise in the cost of farm inputs which in turn leads
to low agricultural production/ food shortage.
iii) Increase in prices of crude oil makes Kenya spend a lot of foreign exchange in
importation lowering foreign currency reserves/ brings about imbalance of trade/
slows down the rate of economic growth.
iv) Increase in oil prices leads to high cost of production leading to slow industrial
growth.
v) Oil scarcity leads to scarcity of by-products of oil leading the scarcity of raw
materials in some industries.
vi) Increase in fuel prices leads to an increase in transport costs which triggers price
increase in in price commodities/ inflation/ reduced tourism activities.
vii) Increase in oil prices leads to high demand for wood fuel leading to deforestation.
viii) Increase in oil prices has led to the development of alternative sources of
energy to reduce overdependence of oil.
ix) Increase in oil prices lead to high cost of goods thus lowering their consumption.

Measures Kenya may take to manage energy crisis.

i) Developing alternative sources of energy like solar to reduce overdependence
on oil.
ii) Encouraging Kenyans to use energy-saving devices so as to reduce the amount
of oil used.
iii) Control the importation of vehicles with high engine capacities to reduce the
consumption of oil.
iv) Improve the flow of traffic in urban centres to avoid delays that lead to high
fuel consumption.
v) Encouraging industries to use coal which is slightly cheaper than petroleum.
vi) Developing nuclear energy to enhance self-sufficiency in energy provision.

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 Management and Conservation of Energy
- Management of energy is the effective planning and control of energy resources.
- Conservation of energy is the careful use and protection of energy resources to
ensure little or no wastage.

Measures the government of Kenya has taken to conserve energy –kcse 2016
i) Encouraging people to use renewable sources of energy in order to reduce the
overreliance of fossil fuels.
ii) Developing energy saving technologies in order to reduce the high consumption
of energy.
iii) Enforcing the legislation against indiscriminate cutting down of trees for fuel
thus conserving existing resources.
iv) Educating the public on the careful use of energy in order to save it.
v) Progress taxation on energy consumption in order to discourage the misuse of
energy.
vi) Proper planning of road networks in urban areas to reduce traffic jam hence
saving on fuel consumption.
vii) Encouraging the use of public transport/ walking/ cycling/ railway in order to
reduce the number of vehicles on the roads/ reducing energy consumption.
viii) Discouraging importation of high fuel consumption vehicles to reduce amount
of fuel used.
ix) Encouraging afforestation/ reafforestation for continuous supply of wood fuel.

Topical Questions.
1. Explain four effects that the increase in oil prices has had on the economies of the oil
importing countries in Africa (8mks)-kcse 2006
2. State four ways in which Kenya can reduce the use of petroleum as a source of energy
(4mks)-kcse 2006
3. Give three effects of liberalization of the oil industry in Kenya (3mks)–kcse 2001
4. Explain three benefits that would result from rural electrification in Kenya (6mks)-
kcse 2002
5. State three benefits Kenya will achieve after drilling oil in Turkana County (3mks)

“END OF TOPIC FIVE”

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