Energy Saving and Conversion
(MSJ0200)
2011. Autumn semester
1. and 2. lectures
Introduction
Course content (1)
•
•
•
•
Energy classification
Sources and utilization
Energy Conversion
Buildings
– Thermal energy conversion in buildings, low energy and
passive houses, eco materials.
– Different heating systems, appliance of heating and
ventilations systems, district heating and local heating.
– Electrical management of buildings. Heating and
ventilation control systems.
Course content (2)
• Industry
– Thermal energy management of industry, utilization of
waste heat.
– Process energy efficiency (logistics, electrical power
management).
• Transportation
– Energy consumption of transportation.
– Emissions from transportations, directives, regulations.
• Different type of internal combustion engines,
hybrid and hydrogen cars.
Course content (3)
• Power Plants.
– Fuels for generating power (fossil, nuclear, renewable).
– Steam power plants.
– Gas turbines power plants.
– Hydraulic power plants.
– Advance fossil fuel power plants.
– Combined-cycle power plant.
– Solar power plant.
• Wind energy conversion. Waste to energy
conversion. Biomass conversion process for energy
recovery. Nuclear power technologies
Course plan (1)
29.08: 1, 2 lectures:
• Description of the course
• Introduction, history of energy conversion
• Energy classification, sources
30.08: 3, 4 lectures:
• Transportation. Energy consumption of
transportation.
• Emissions from transportations, directives,
regulations.
• Different type of internal combustion engines,
hybrid and hydrogen cars
Course plan (2)
31.08: 5, 6 lectures:
• Energy conversion. Buildings. Thermal energy
conversion in buildings, low energy and
passive houses.
• Different heating systems, district heating and
local heating.
01.09: 7, 8 lectures:
• Nuclear power technologies
Course plan (3)
02.09: 9, 10 lectures:
• Fuels for generating power (fossil, nuclear,
renewable).
• Shale gas
• Steam power plants.
05.09: 11, 12 lectures:
• Combined-Cycle Power Plants
• Advance fossil fuel power plants.
Course plan (4)
06.09: 13, 14 lectures:
• Wind energy
• Solar power plants
07.09: 15, 16 lectures:
• CHP using gas fired Internal combustion engine
• Stirling engine
• Industry
– Thermal energy management of industry,
utilization of waste heat.
– Process energy efficiency (logistics, electrical
power management).
Course plan (6)
08.09: Excursion:
• Narva power plants
09.09: 17, 18 lectures:
• Gas turbines
• Biomass conversion process for energy
recovery
• Waste to energy conversion.
Course plan (7)
12.09: SEMINAR:
• SEMINAR (1-st part)
13.09: SEMINAR:
• SEMINAR (2-nd part)
xxx.09: EXAM
SEMINAR
Topic:
Environmental problems, which appear
due to the energy conversion (everyone
makes a presentation, length ca 15min)
Deadline: 09.sept (by e-mail
asiirde@staff.ttu.ee)
Oral speech: 12. and 13. sept
References
• „Energy Efficiency“, F.Kreith, R.E.West; CRC Press
• „Sustainable Energy Systems Engineering“,
P.Gevorkian; McGraw-Hill book company
• „Principles of Energy Conversion“, A.W.Culp jr;
McGraw-Hill book company
• „Energy Systems and Sustainability“, G.Boyle,
B.Everett, J.Ramage; Oxford University Press
• „Energy Conversion“, D.Y.Goswani, F.Keith; CRC
Press
1. and 2. Lectures (29.08)
Description of the course
Introduction, history of energy
conversion
Energy classification, sources
…
Introduction
• Energy conversion engineering (or heat-power
engineering) has been one of the central
themes in the development of the engineering
profession.
• It is concerned with the transformation of
energy from sources such as fossil and nuclear
fuels and the sun into conveniently used forms
such as electrical energy, rotational and
propulsive energy, and heating and cooling.
Introduction (II)
• Then came the oil embargo of the 1970s, high fuel
prices…..
• The limitations of the Earth’s resources and
environment started to come into clearer focus.
• The public and legislatures began to recognize that
air pollution.
• Produced by factories, power plants, and
automobiles and other forms of environmental
pollution were harmful.
Introduction (III)
• These and other influences have been helping to
create a more favorable climate for consideration, if
not total acceptance, of energy conversion
alternatives and new concepts.
• Examples are combined steam and gas turbine
cycles, rotary combustion engines, solar and
windmill power farms, stationary and vehicular gas
turbine power plants, cogeneration, photovoltaic
solar power, turbocharged engines, fluidized-bed
combustors, and coal-gasification power plants.
Some Significant Events in the
History of Energy Conversion
• The historical progress of industry and
technology was slow until the fundamentals
of thermodynamics and electromagnetism
were established in the ninteenth century.
Conclusion
• Since energy conversion engineering is deeply
rooted in thermodynamics, fluid mechanics, and
heat transfer, these disciplines are necessary for
understanding, analysis, and design in the field
of energy conversion.
Energy:
Forms and Changes
What is energy
• Energy is the power to change things. It is the
ability to do work.
• Energy lights our cities, powers our vehicles,
and runs machinery in factories. It warms and
cools our homes, cooks our food, plays our
music, and gives us pictures on television.
• Joule - A unit of energy. One joule equals
0.2388 calories
Nature of Energy
• Energy is all around you!
–You can hear energy as sound.
–You can see energy as light.
–And you can feel it as wind.
Nature of energy
• You use energy when you:
– hit a softball.
– lift your book bag.
-…………...
Living organisms need energy for growth and
movement
Nature of energy
• What is energy that it can be involved in so
many different activities?
– Energy can be defined as the ability to do
work.
– If an object or organism does work (exerts a
force over a distance to move an object) the
object or organism uses energy.
Energy and Work
• Because of the direct connection
between energy and work, energy is
measured in the same unit as work:
joules (J).
• In addition to using energy to do work,
objects gain energy because work is
being done on them.
Heat and Work
Heat and Work Are Not Properties
Mechanics teaches that work can change the kinetic energy
of mass and can change the elevation or potential energy
of mass in a gravitational field. Thus work performed by an
outside agent on the system boundary can change the
energy associated with the particles that make up the
system. Likewise, heat is energy crossing the boundary of a
system, increasing or decreasing the energy of the
molecules within. Thus heat and work are not properties of
state but forms of energy that are transported across
system boundaries to or from the environment. They are
sometimes referred to as energy in transit. Energy
conversion engineering is vitally concerned with devices
that use and create energy in transit.
Heat is not energy
2 kJ
thermal energy
2 kJ
heat
2 kJ
thermal energy
Heat and Work
• In addition to using energy to do work,
objects gain energy because work is
being done on them.
• Because of the direct connection
between energy and work, energy is
measured in the same unit as work:
joules (J).
Energy forms
The five main forms of energy are:
–Heat ?
–Chemical
–Electromagnetic
–Nuclear
–Mechanical
Heat Energy- (internal energy)
• The internal motion of the atoms is called
heat energy, because moving particles
produce heat.
• Heat energy can be produced by friction.
• Heat energy causes changes in temperature
and phase of any form of matter.
Chemical Energy
• Chemical Energy is required to bond atoms
together.
• And when bonds are broken, energy is
released.
Fuel and food are forms of stored chemical
energy.
Electromagnetic Energy
• Power lines carry electromagnetic energy into your
home in the form of electricity.
• Electromagnetic Energy
• Light is a form of electromagnetic energy.
• Each color of light (Roy G Bv) represents a different
amount of electromagnetic energy.
• Electromagnetic Energy is also carried by X-rays,
radio waves, and laser light.
Mechanical Energy
• When work is done to an object, it acquires
energy. The energy it acquires is known as
mechanical energy.
• When you kick a football, you give mechanical
energy to the football to make it move
Energy Conversion
• Energy can be changed from one form to
another. Changes in the form of energy are
called energy conversions.
Conversion
All forms of energy can be converted into other forms.
– The sun’s energy through solar cells can be converted
directly into electricity.
– Green plants convert the sun’s energy (electromagnetic)
into starches and sugars (chemical energy).
– In an automobile engine, fuel is burned to convert
chemical energy into heat energy. The heat energy is
then changed into mechanical energy.
Chemical  Heat Mechanical
Other energy conversions
– In an electric motor, electromagnetic energy is
converted to mechanical energy.
– In a battery, chemical energy is converted into
electromagnetic energy.
– The mechanical energy of a waterfall is converted
to electrical energy in a generator.
States of Energy
• The most common energy conversion is the
conversion between potential and kinetic
energy.
• All forms of energy can be in either of two
states:
– Potential
– Kinetic
States of Energy
Kinetic and Potential Energy:
• Kinetic Energy is the energy of motion.
• Potential Energy is stored energy.
Kinetic Energy
• The energy of motion is called kinetic energy.
• The faster an object moves, the more kinetic
energy it has.
• The greater the mass of a moving object, the
more kinetic energy it has.
• Kinetic energy depends on both mass and
velocity.
KE
KE= (massxveocity2) x 0.5
• What has a greater affect of kinetic energy,
mass or velocity
Potential Energy
• Potential Energy is stored energy.
– Stored chemically in fuel, the nucleus of
atom, and in foods.
– Or stored because of the work done on it:
• Stretching a rubber band.
• Winding a watch.
• Pulling back on a bow’s arrow.
• Lifting a brick high in the air.
Gravitational Potential Energy
• Potential energy that is dependent on height
is called gravitational potential energy.
The Law of Conservation of Energy
Energy can be neither created nor destroyed by
ordinary means.
– It can only be converted from one form to
another.
– If energy seems to disappear, then scientists
look for it – leading to many important
discoveries.
Law of Conservation of Energy
• In 1905, Albert Einstein said that mass and
energy can be converted into each other.
• He showed that if matter is destroyed, energy
is created, and if energy is destroyed mass is
created.
E = MC2
The different sources of energy
The different sources are:1. Fossil fuels
2. Hydro power plant
3. Biomass
4. Wind energy
5. Solar energy
6. Geo thermal energy
7. Ocean thermal energy
8. Tidal energy
9. Wave energy
10.Nuclear energy
RENEWABLE- NON-RENEWABLE
• RENEWABLE:
--CAN BE REGENERATED IN A RELATIVELY
SHORT PERIOD OF TIME; UNLIMITED
• NON-RENEWABLE:
--CAN NOT BE REPLACED IN A SHORT
AMOUNT OF TIME; LIMITED
Fossil fuels
• Coal, oil and gas are called "fossil fuels" because they have
been formed from the organic remains of prehistoric plants
and animals.
• Crude oil (called "petroleum") is easier to get out of the
ground than coal, as it can flow along pipes. This also
makes it cheaper to transport.
• Natural gas provides around 20% of the world's
consumption of energy, and as well as being burnt in power
stations, is used by many people to heat their homes.
It is easy to transport along pipes, and gas power stations
produce comparatively little pollution.
• Fossil fuels are not a renewable energy resource.
Once we've burned them all, there isn't any more, and our
consumption of fossil fuels has nearly doubled every 20
years since 1900.
This is a particular problem for oil, because we also use it to
make plastics and many other products.
Biomass
• Biomass is a renewable energy resource derived from the
carbonaceous waste of various human and natural activities.
It is derived from numerous sources, including the byproducts from the timber industry, agricultural crops, raw
material from the forest, major parts of household waste
and wood.
• Biomass does not add carbon dioxide to the atmosphere as
it absorbs the same amount of carbon in growing as it
releases when consumed as a fuel. Its advantage is that it
can be used to generate electricity with the same equipment
or power plants that are now burning fossil fuels.
• At present, biogas technology provides an alternative
source of energy in rural India for cooking. It is particularly
useful for village households that have their own cattle.
Through a simple process cattle dung is used to produce a
gas, which serves as fuel for cooking. The residual dung is
used as manure.
Wind energy
• Wind energy is the kinetic energy associated with the
movement of atmospheric air. It has been used for
hundreds of years for sailing, grinding grain, and for
irrigation. Wind energy systems convert this kinetic
energy to more useful forms of power.
• Wind turbines transform the energy in the wind into
mechanical power, which can then be used directly
for grinding etc. or further converting to electric
power to generate electricity. Wind turbines can be
used singly or in clusters called ‘wind farms’. Small
wind turbines called aero-generators can be used to
charge large batteries.
Solar
• A solar cell or photovoltaic cell is a machine that
converts sunlight directly into electricity by
the photovolts effect.
• Photovoltaics is the field of technology and research
related to the application of solar cells in producing
electricity for practical use.
• The photovoltaic effect, which causes the cell to
convert light directly into electrical energy, occurs in
the three energy-conversion layers.
Solar heating
• Solar heating systems are generally composed of
solar thermal collectors, a fluid system to move the heat
from the collector to its point of usage.
• The system may use electricity for pumping the fluid, and
have a reservoir or tank for heat storage and subsequent
use.
• The systems may be used to heat water for a wide variety
of uses, including home, business and industrial uses.
• In many climates, a solar heating system can provide up to
85% of domestic hot water energy.
• In many northern European countries, combined hot water
and space heating systems are used to provide 15 to 25%
of home heating energy.
Ocean Thermal Energy
• The main objective of ocean thermal energy or Ocean Thermal
Energy Conversion (OTEC) is to turn the solar energy trapped by the
ocean into useable energy.
• This kind of energy is found in tropical oceans where the water
temperature differs from surface to deeper into the sea. On the
ocean surface it can be at least 20 C hotter or cooler than the
temperature at a deeper sea level.
• Three approaches, open cycle OTEC, closed cycle OTEC and hybrid
cycle OTEC have been created in the past fifty years.
• The variety of products and services are the major advantage of OTEC
plants. Ocean thermal is also relatively clean and will not produce
more pollutants that contribute to global warming.
• OTEC plants are most suitable for islands around the tropical region
of the east Pacific Ocean. This is because OTEC plants can provide
both energy and pure water at the same time with a relatively low
cost. It is also because the ocean in that region has greater
temperature differences, which is about 24 oC.
Wave energy
• In many areas of the world, the wind blows with enough
consistency and force to provide continuous waves. There
is tremendous energy in the ocean waves.
• WAVE POWER DEVICES extract energy directly from the
surface motion of ocean waves or from pressure
fluctuations below the surface.
• Wave technologies have been designed to be installed
in nearshore, offshore, and far offshore locations.
• While all wave energy technologies are intended to be
installed at or near the water's surface, they differ in their
orientation to the waves with which they are interacting
and in the manner in which they convert the energy of the
waves into other energy forms, usually electricity.
Geothermal energy
• Geothermal energy is heat from within the
earth. We can use the steam and hot water
produced inside the earth to heat buildings or
generate electricity.
• Geothermal energy is a renewable energy
source because the water is replenished by
rainfall and the heat is continuously produced
inside the earth
Nuclear energy
• Changes can occur in the structure of the nuclei of
atoms. These changes are called nuclear reactions.
Energy created in a nuclear reaction is called nuclear
energy, or atomic energy.
• When the nucleus splits (fission), nuclear energy is
released in the form of heat energy and light energy.
• Nuclear energy is also released when nuclei collide at
high speeds and join (fuse).
Vocabulary Words
energy
mechanical energy
heat- thermal energy
chemical energy
electromagnetic energy
nuclear energy
kinetic energy
potential energy
gravitational potential energy
energy conversion
Law of Conservation of Energy
RENEWABLE
NON-RENEWABLE
Fossil
THANK YOU FOR YOUR ATTENTION!
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