ENERGY
SOURCES
Renewable and non-renewable sources
• Renewable - an energy source that can be
replenished in a short period of time
• Non-renewable - an energy source that cannot be
recreated in a short period of time
• Both can be used to produce secondary energy
sources - electricity and hydrogen.
Renewable and non-renewable sources (cont.)
Renewable energy sources include:
 solar energy, which comes from the sun and
can be turned into electricity and heat
 wind
 geothermal energy from inside the earth
 biomass from plants
 hydropower
 ocean energy
Renewable and non-renewable sources (cont.)
Non-renewable energy sources include:
 fossil fuels - oil, natural gas, and coal
 uranium, whose atoms when split (nuclear
fission) create heat and ultimately electricity.
Secondary Energy Sources
Secondary energy refers to the more convenient forms
of energy which are transformed from other,
primary, energy sources through energy conversion
processes.
Electricity is a secondary energy source
- from the conversion of primary sources of energy like
coal, natural gas, oil, nuclear power and etc.
Secondary sources of energy (energy carriers) -- store,
move & deliver energy to consumers.
e.g. We convert energy to electricity because it is easier
for us to move and use.
Secondary Energy Sources (cont.)
• Hydrogen is an energy carrier too, especially for
the future.
• Sending electricity a long way costs four times as
much as shipping hydrogen by pipeline.
About 9 million metric tons of hydrogen are produced in US annually,
enough to power 20-30 million cars or 5-8 million homes.
NASA is the primary user of hydrogen as an energy fuel; it has used hydrogen
for years in the space program.
Hydrogen batteries, called fuel cells, power the shuttle’s electrical systems.
The only by-product is pure water, which the crew uses as drinking water.
Top 10 Energy Sources of the Future
1. Nuclear fusion
2. Flying Wind
Farms
3. Bio-fuels
(algae)
4. Solar
Windows
5. Nuclear Waste
6. Geothermal heat from
underground lava
beds
7. Hydrogen (fuel cells)
8. Tidal Power
9. Human Power
ALTERNATIVE ENERGIES –
(Existing)
• Solar
• Ocean Wave
• Hydropower
• Ocean Tides
• Biomass
• Geothermal
• Wind
• Ocean Thermal Energy
• Ice Harbour Dam
Solar energy – thermal devices
Solar thermal devices use direct heat from the sun,
concentrating it in some manner to produce heat at
useful temperatures.
Currently, solar thermal devices do everything from
heating swimming pools to creating steam for electricity
generation.
Solar Water Heaters
Solar energy – photovoltaic devices
Photovoltaic devices use semi-conducting materials to
convert sunlight directly into electricity.
Solar radiation - varies with changing atmospheric
conditions (clouds and dust) & the changing position of
the Earth relative to the sun.
Wind
• Winds are created by uneven heating of the
atmosphere by the sun, irregularities of the Earth's
surface, and the rotation of the Earth.
• As a result, winds are strongly influenced and
modified by local terrain, bodies of water, weather
patterns, vegetative cover, and other factors.
• The wind flow, or motion of energy when harvested
by wind turbines, can be used to generate
electricity.
Geothermal energy
• Geothermal energy is contained in underground reservoirs
of steam, hot water, and hot dry rocks.
• Hot water or steam from geothermal reservoirs in the
Earth's crust is supplied to steam turbines at electric
utilities that drive generators to produce electricity.
• Moderate-to-low temperature geothermal resources are
used for direct-use applications such as district and space
heating.
• Lower temperature, shallow ground, geothermal resources
are used by geothermal heat pumps to heat and cool
buildings.
Biomass energy
• Biomass energy is derived from 3 distinct energy sources:
wood, waste, and alcohol fuels.
• Wood energy is derived both from direct use of harvested wood
(chips) as a fuel and from wood waste streams.
• The largest source of energy from wood is pulping liquor or
“black liquor,” a waste product from processes of the pulp and
paper industry.
• Waste energy is the second-largest source of biomass
energy. The main contributors of waste energy are municipal
solid waste (MSW), manufacturing waste, and landfill gas.
• Biomass alcohol fuel, or ethanol, is derived almost exclusively
from oil palm, rice husk, bagasse and forest residue.
Hydropower
• Water - leading renewable energy source used by electric
utilities to generate electric power.
• Hydroelectric plants operate where suitable waterways are
available.
• Generating electricity using water has several advantages
water is a source of cheap power
no fuel combustion, less air pollution compared to fossil
fuel plants.
• Limitations include environmental impacts caused by
damming rivers and streams, which affects the habitats of
the local flora and fauna.
Ice Harbour Dam
Ocean energy
• Ocean energy draws on the energy of
 Ocean waves
 Ocean tides
 thermal energy (heat) stored in the ocean
Wave Energy
• Wave energy is generated by the movement of a device
either floating on the surface of the ocean or fixed to the
ocean floor.
• Wave conversion devices that float on the surface have
joints hinged together that bend with the waves. This
kinetic energy pumps fluid through turbines and creates
electric power.
• Stationary wave energy conversion devices use
pressure fluctuations produced in long tubes from the
waves swelling up and down. This bobbing motion
drives a turbine when critical pressure is reached.
Tidal Energy
• Tidal energy traditionally
involves building a dam
across the opening to a
tidal basin.
• The dam includes a
water-gate that is opened
to allow the tide to flow
into the basin; the watergate is then closed.
• As the sea level drops,
traditional hydropower
technologies can be used
to generate electricity
from the elevated water in
the basin.
Ocean energy (cont.)
Ocean Thermal Energy Conversion (OTEC)
Systems
– A great amount of thermal energy (heat) is
stored in the world's oceans. Each day, the
oceans absorb enough heat from the sun to
equal the thermal energy contained in 250
billion barrels of oil.
– OTEC systems convert this thermal energy into
electricity; often while producing desalinated
water.
Fuel-mix for electricity generation –
Malaysia
Source: Oh et al., 2010
Assessment Criteria
Source: Ahmad and Tahar, 2014