Gives an overview of techhnology available in the field of clean energy.

1. Dr. Muhammad Uzair
Assistant Professor
Department of Mechanical Engineering, NED UET
uzair@neduet.edu.pk
Clean Energy Technology

2. IMPORTANT NOTE
Softcopy of presentations, research
papers and other study material will
be shared on Google Drive link or By
Email

3. Outline
• Overview
• Solar Energy
• Wind Energy
• Hydropower
• Biomass Energy
• Tidal and Wave Energy
• Geothermal Energy

4. Books
• John Twidell and Tony Weir, “Renewable Energy
Resources”, Routledge, 2014.
• Godfrey Boyle, “Renewable Energy: Power for a
Sustainable Future”, Oxford University Press, 2004.
• John A. Duffie William A. Beckman , “Solar Engineering of
Thermal Processes”, John Wiley & Sons, Inc.

5. Class Learning Outcomes
S. No. CLOs Taxonomy
1
Explain fundamental characteristics of
different clean energy sources and
mechanism for harnessing this
technology
Cognitive
Level 2*
2
Apply methodology for extraction of
power through various clean energy
sources
Cognitive
Level 3*
3
Compare environmental aspects of
clean energy systems and conventional
fossil fuel systems
Cognitive
Level 4*

6. OVERVIEW

7. Overview
7
All the renewable energy sources are principally derived
from the enormous power of Sun's radiation.

8. Overview
8
These renewable energy sources are at once, the most
ancient and now, the most modern forms of energy used
by humanity.

9. Overview
9
Solar power is one of the ultimate sources of energy
upon which early human societies were based.

10. Overview
1
0
When our ancestors first used fire, they were
harnessing the power of photosynthesis which is a
solar driven process by which plants are created from
water and atmospheric carbon dioxide.

11. Overview
1
1
Societies went on to develop ways of harnessing the
movements of water and wind to grind corn, irrigate
crops and propel ships.

12. Overview
Both the natural movements of water and wind are
caused by solar heating of the oceans and
atmosphere.

13. Overview
As civilizations became more sophisticated,
architects began to design buildings to take
advantage of the Sun’s energy by enhancing their
natural use of its heat and light, so reducing the
need for artificial sources of warmth and
illumination.

14. Overview
Technologies for harnessing the power of Sun, water
and wind continued to improve right up to the early
years of the industrial revolution.

15. Overview
However, by then the advantages of coal, the first of
the fossil fuels to be exploited on a large scale, had
become apparent.

16. Overview
These highly-concentrated energy sources soon
displaced wood, wind and water in the homes,
industries and transport systems of the industrial
nations.

17. Overview
Today the fossil fuel trio of coal, natural gas and oil
provide over 80% of the world’s energy.

18. Overview
Concerns about the adverse environmental and
social consequences of fossil fuel use, such as air
pollution, oil spills, mining accidents, deforestation
and about the finite nature of supplies, have been
voiced intermittently for several decades.

19. Overview
But it was not until the
1970s, with the steep price
rises of the ‘oil crisis’ and the
advent of the environmental
movement, that humanity
began to take more seriously
the prospect of fossil fuels
‘running out’, and the
possibility that their
continued use could be
destabilizing the planet’s
natural ecosystems and the
global climate.

20. Overview
The development of nuclear energy following World
War II raised hopes of a cheap, plentiful and clean
alternative to fossil fuels.

21. Overview
However, nuclear power development has stalled in
some countries in recent years, due to increasing
concern about safety, cost, waste disposal and
weapons proliferation, although in other countries
nuclear expansion is continuing.

22. Overview
Continuing concerns
about the
‘sustainability’ of
both fossil and
nuclear fuel use
have been a major
catalyst of renewed
interest in the
renewable energy
sources in recent
decades.

23. Overview
Now, what is a Sustainable Energy Source?
Sustainable energy source is one which help
this world in meeting its present needs
without depleting of serving next generation’s
needs.

24. Overview
Sustainable energy does not involve
significant pollutant emissions or other
environmental problems.

25. Overview
Also, sustainable energy does not involve the
spread of substantial health hazards or social
injustices.

26. Overview
At present, oil and gas present at large scale
and thus are sustainable energy sources.

27. Overview
What is a Renewable
Energy Source?
Renewable energy
source include such a
natural source which
can be replaced by
natural ecological
cycles. That is, they
renew thus never gets
deplete.

28. Overview
Tidal, wave, geothermal, wind and solar energies
are counted as renewable energy sources.

29. Overview
The energy
coming from
sun and wind
can be
characterized
as both
sustainable
and
renewable
energy
sources.

30. COMPARISON OF
RENEWABLE AND
CONVENTIONAL ENERGY
SYSTEMS

31. Examples
Renewable Energy Sys.
Wind, solar, biomass, tidal
etc.
Conventional Energy Sys.
Coal, oil, gas etc.

32. Source
Renewable Energy Sys.
Natural local environment.
Conventional Energy Sys.
Concentrated stock.

33. Initial average intensity
Renewable Energy Sys.
Low intensity, less than
300 W/m2
Conventional Energy Sys.
High intensities, more than
100,000 W/m2

34. Lifetime of supply
Renewable Energy Sys.
Infinite
Conventional Energy Sys.
Finite

35. Cost at source
Renewable Energy Sys.
Free
Conventional Energy Sys.
Increasingly expansive

36. Equipment cost per kW capacity
Renewable Energy Sys.
Expensive,
commonly 1000 USD/kW
Conventional Energy Sys.
Moderate, perhaps 500
USD/kW (without
emissions control)
Expansive, perhaps more
than 1000 USD/kW (with
emissions control)

37. Variation in output
Renewable Energy Sys.
Fluctuating, most of the
times, unpredictable
Conventional Energy Sys.
Steady

38. Scale
Renewable Energy Sys.
Small and moderate scale
often economic, large
scale may present
difficulties
Conventional Energy Sys.
Increased scale often
improves supply costs,
large scale frequently
favored

39. Pollution and environmental damage
Renewable Energy Sys.
Usually little environment
harm, especially at
moderate scale
Conventional Energy Sys.
Environmental pollution
intrinsic and common,
specially of air and water

40. Pollution and environmental damage
Renewable Energy Sys.
Usually little environment
harm, especially at
moderate scale
Conventional Energy Sys.
Environmental pollution
intrinsic and common,
specially of air and water

41. ENERGY SOURCE
COMPARISON

42. Solar Energy
Pros
• Nonpolluting
• Most abundant energy
source available
• Systems last 15-30
years
Cons
• High initial investment
• Dependent on sunny
weather
• Supplemental energy
may be needed in low
sunlight areas
• Requires large physical
space for PV cell panels
• Limited availability of
poly-silicon for panels

43. Wind Energy
Pros
• No emissions
• Affordable
• Little disruption of
ecosystems
• Relatively high output
Cons
• Output is proportional
to wind speed
• Not feasible for all
geographic locations
• High initial
investment/ongoing
maintenance costs
• Extensive land use

44. Biomass Energy
Pros
• Abundant supply
• Fewer emissions than
fossil fuel sources
• Can be used in diesel
engines
• Auto engines easily
convert to run on
biomass fuel
Cons
• Source must be near
usage to cut
transportation costs
• Emits some pollution as
gas/liquid waste
• Increases emissions of
nitrogen oxides, an air
pollutant
• Uses some fossil fuels
in conversion

45. Geothermal Energy
Pros
• Minimal environmental
impact
• Efficient
• Power plants have low
emissions
• Low cost after the
initial investment
Cons
• Geothermal fields
found in few areas
around the world
• Expensive start-up costs
• Wells could eventually
be depleted

46. Wave and Tidal Energy
Pros
• Consistent in terms of
power generation
• Creates no greenhouse
gas emissions or water
pollutants
• Less operating costs or
labor costs
• More than 80%
efficient
Cons
• Sea life could be
harmed
• Large footprints could
reduce shipping and
recreation areas
• High initial and
installation costs
• Implemented on few
sites

47. Coal
Pros
• Abundant supply
• Currently inexpensive
to extract
• Reliable and capable of
generating large
amounts of power
Cons
• Emits major
greenhouse gases/acid
rain
• High environmental
impact from mining and
burning, although
cleaner coal-burning
technology is being
developed

48. Petroleum
Pros
• Efficient transportation
fuel for the world
• Basis of many products,
from prescription drugs
to plastics
• Economical to produce
• Easy to transport
Cons
• High CO2 emissions
• Found in limited areas
• Supply may be
exhausted before
natural gas/coal
resources
• Possible environmental
impact from
drilling/transporting

49. Natural gas
Pros
• Widely available
• Cleanest-burning fossil
fuel
• Often used in
combination with other
fuels to decrease
pollution in electricity
generation
Cons
• Transportation costs
are high
• Lack of infrastructure
makes gas resources
unavailable from some
areas
• Burns cleanly, but still
has emissions
• Pipelines impact
ecosystems

50. Nuclear
Pros
• No greenhouse gases or
CO2 emissions
• Efficient at
transforming energy
into electricity
• Uranium reserves are
abundant
• Refueled yearly (unlike
coal plants that need
coal every day)
Cons
• Higher capital costs due
to safety, emergency,
containment,
radioactive waste, and
storage systems
• Problem of long-term
storage of radioactive
waste
• Heated waste water
harms aquatic life

51. BEST ENERGY SOURCE

52. It depends!
• Is it a renewable or nonrenewable source?
• What are the capital and setup costs?
• What are the ongoing operating costs?
• What size of energy storage is required?
• How efficient is it to produce one unit of
energy?
• Can it be produced on a large scale?
• What is the cost to the consumer?
• What impact will it have on the environment?

53. THANKS!