Environmental Science: Energy resources

HANOI UNIVERSITY OF SCIENCE

---***--Environmental science

Energy resources
Group 6

Hanoi, May 13th, 2011


Energy resources
Prof. Nguyễn Xuân Cự

Group 6
Vũ Tuấn Tài
Nguyễn Thanh Tùng
Nguyễn Việt Hà
Lê Hồng Minh
Nguyễn Tá Nam
Hà Công Đức


Contents
I.
II.
III.
IV.
V.

What is energy?
Energy resources

Energy consumption
Energy conservation
Sustainable energy


I.

What is energy?

1.1 Definition
- The word energy derives from the Greek ”energeia”
- First appears in 4th century BC
- Energy is the capacity of a system to do work. Energy is the
power to change things

1.2 For example
That system may be:
 A jet, carrying hundreds of passengers across the ocean.
 A baby’s body, growing bone cells.
 A kite, rising on the wind.
 Or a wave of light crossing a space.

1.3 Two types of energy
- Renewable
- Non-Renewable

1.3.1 Renewable energy
-Wind
-Solar
-Hydropower

-Biomass
-Water
-Geothermal power


Advantages

Disadvantages

 Sustainable and will
never run out
 Derived from natural
 Reduces the costs of
operation
 Minimal impact on the
environment.

 Depends on the weather
 Difficult to generate the
quantities of electricity

1.3.2 Non-Renewable energy
- Coal
- Natural gas
- Petroleum
- Uranium
- Propane

Advantages

Disadvantages


 Relatively cheap fuel and
readily available

 Can run out
 Photochemical pollution:
acid rain
 Greenhouse gases
 Global warming

1.4 Is nuclear power renewable or nonrenewable?
 Many environmental groups are fundamentally opposed to
the notion that nuclear power is a renewable form of energy
— on the grounds that it produces harmful waste byproducts
and relies on extractive industries to procure fuel like
uranium.
 Even so, the nuclear industry and pro-nuclear officials from
countries including France have been trying to brand the
technology as renewable, on the grounds that it produces
little or no greenhouse gases.
 In conclusion, this is still problem was discussed

II.

Some typical energy resources

1.Coal
1.1 Definition

• Coal is composed primarily of carbon along with variable
quantities of other elements,
chiefly sulfur, hydrogen, oxygen and nitrogen
• Main types: lignite, sub-bituminous, bituminous and
anthracite
• Anthracite is the hardest, has the most carbon, giving it a
higher heat value
• Lignite is the softest coal, has the least amount of carbon
• Different types of coal are characterized by their unique
properties, which produce different results when burned.
• Coal is a hydrocarbon-rich, fossil fuel resources, was formed
millions of years ago
• Coal mining: surface and underground

1.2 Coal mine distribution
The largest coal mine is Tavan Tolgoi in Mongolia


2. Petroleum
2.1 Definition
• Petroleum or crude oil is a naturally occurring flammable
liquid consisting of a complex mixture of hydrocarbons of
various molecular weights and other liquid organic
compounds, that are found in geologic formations beneath
the Earth's surfaces.
• Petroleum has a lot of energy, we can turn it into different
fuels: gasoline, kerosene, heating oil
• Petroleum is non-renewable and a fossil fuel

2.2 Top ten oil reserves countries


III.Energy consumption
3.1 Who use energy


The U.S. Department of Energy divides energy users into four groups:
Residential, commercial, industrial, and transportation. These groups
are called the sectors of the economy.

3.2 Five economic sectors
-Residential and Commercial Sectors
Any place where people live is considered a residential building.
Commercial buildings include offices, stores, hospitals,
restaurants, and schools. Residential and commercial buildings are
grouped together because they use energy in the same ways—for
heating and cooling, lighting, heating water, and operating
appliances.
+Heating & Cooling:
It takes a lot of energy to heat rooms in winter and cool them in
summer. Half of the energy used in the average home is for heating
and cooling rooms.
+ Lighting:
Homes and commercial buildings also use energy for lighting.
+ Appliances:
Home appliances have become more energy efficient. Water
heaters, refrigerators, clothes washers, and dryers all use much less
energy today than they did 25 years ago.

-Industrial Sector:
The United States is a highly industrialized country. We use a lot of
energy. Today, the industrial sector uses 31 percent of the nation’s
energy.
+Petroleum Refining
The United States uses more petroleum than any other energy
source. Petroleum provides the U.S. with about 37 percent of the
energy we use each year


+Metal Manufacturing:
The steel industry uses energy to turn iron ore and scrap metal into
steel. Hundreds of the products we use every day are made of steel. It
is a very hard, durable metal and it must be heated to very high
temperatures to manufacture it.
+Paper Manufacturing: Energy is used in every step of paper
making. Energy is used to chop, grind, and cook the wood into pulp.
+Chemical Manufacturing: Chemicals are an important part of our
lives. We use chemicals in our medicines, cleaning products, fertilizers
and plastics, as well as in many of our foods.
+Cement Manufacturing: Some people think the United States is
becoming a nation of concrete. New roads and buildings are being built
everywhere, every day. We use lots of concrete. Concrete is made
from cement, water, and crushed stone. A lot of energy is used in
making cement. The process requires extremely high temperatures—up
to 3,500 degrees Fahrenheit.
-Transportation Sector:
The transportation sector uses twenty-seven percent of the energy
supply to moving people and goods from one place to another.
The vehicles include: Train, plane, boat, motorbike etc

3.3 Energy world consumption


• World primary energy demand projected in RS to expand by
almost 60% from 2002 to 2030, average annual increase of
1.7% per year.
• Projected rate of growth is, nevertheless, slower than over
the past three decades, when demand grew by 2% per year.
• Demand reaches 16.5 billion toes in 2030 up from 10.3 toes
in 2002.
• Oil will remain single largest fuel in the global primary
energy mix, though its share will fall marginally.
Demand for gas grows at 2.3% per year in 2002-2030 – fastest rate of
any fossil fuel. By 2030, gas use will be 90% higher than now, and gas
will have overtaken coal as world’s 2nd-largest energy source.

III. Energy conservation
Most of the energy we use is wasted!


What’s the problem?
It isn’t matter we turn off the light or turn down the air
conditioning.
It’s a technology challenge. With the way we use energy
most of energy in fuel is lost as waste heat, becoming a
form of environmental pollution.
Many conservation techniques are applied. Most of them
are relatively simple and highly cost effective.
The most common example is compact bulbs

Compact bulbs produce four times as much as an
incandescent bulb of the same wattage and last ten times as
long.
Although compact bulb’s cost is higher but total life saving
$30 to $50 per bulb.
LEDs are even more extremely. LEDs consuming 90% less
energy and lasting hundreds of times as long as ordinary
light bulbs.
For some other example:
Household energy losses can be reducing by ½ to ¾
through insulation…
New washing machines use 35% less water in the past. It
will cut water use by 40 trillion liters.


Something you can do to save energy!

IV. Sustainable energy
A number of types of energy can be thought of as sustainable, and
many governments promote the use of sustainable energy and the
development of new types of energy generating technology which fit
within this model. Increasing rates of energy consumption around the
world have led to a corresponding rise in concerns about where this
energy comes from.
1. Biomass renewable energy is energy derived usually from plant
waste, such as beet, corn, or sugarcane waste that can be used to
produce ethanol fuel for cars, aircraft, and other forms of


transportation. Biomass renewable energy offers a potentially

limitless supply of energy to modern civilization, because most of the
energy derived from biomass was generated first by the sun.
Renewable energies such as those produced from biomass products
are also seen as generally less harmful to the environment, as less
pollution is generated in the process of manufacturing and using them.
Unlike fossil fuels, biomass renewable energy can also be
replenished over a short time period by simply planting more of the
crop that is used to generate the fuel or harvesting more of an
otherwise unused plant from nature. It is, therefore, dependent on
proper land management. The proper use of freshwater resources and
soil conservation in a sustainable manner must be the focus of
biomass energy production if it is to be a long-term solution to
growing energy needs.
In the United States, biomass renewable energy as of 2002 supplied
six times as much energy as geothermal renewable energy, solar
power, and wind energy resources combined. Estimates are that 3%
of all energy in the United States is supplied by biomass renewable
resources. Globally, 14% of energy needs are met by biomass fuels.
2. Solar electric energy refers to power derived from the sun’s
radiation that is used to generate electricity. Since ancient times, the
sun’s heat and light has been harnessed in many ways. Only within
recent decades, however, have technologies like the photovoltaic or
solar cell allowed solar energy to help power electrically dependent
equipment, vehicles, and even entire homes. Since it is a renewable
resource, solar energy is generally favored over non-renewable fossil
fuels like coal and oil. In addition, most solar technologies used to
collect and convert solar electric energy have no moving parts, and
emit no noise or pollutants, making them an attractive alternative
energy source to fossil fuels.

Some applications of solar technology include sustainable
architecture, agriculture, and water treatment. Depending on the way
these technologies capture, convert, and distribute solar energy, they
are considered either active or passive solar. Photovoltaic and solar
thermal units are considered active solar, as these devices directly
collect, convert, and distribute the sun’s energy as electric power.
Passive solar methods might include home designs that incorporate
the presence of abundant sunlight to provide both natural light and
heat within a structure.
Countries throughout the world have begun to adopt solar electric
energy as a fossil fuel alternative. While the installation costs of solar
power plants like photovoltaic arrays and solar troughs may be
considerable, the long-term benefits of solar electric energy include
less dependence on non-renewable resources, and therefore fewer
pollutants or byproducts. Solar electric energy is an intermittent
source of energy, which means one may easily forecast when the sun
will and will not generate energy in specific regions. This ability has
helped solar engineers and devise the best technologies and locations
for harnessing the most amount of solar energy.
Aside from the use of solar electric energy to power, heat and cool a
home, there are various other applications of solar energy. Continents
including Australia and the United States have held competitions
since the 1980s to construct solar-powered cars that can achieve
average speeds of almost 60 mph (96.56 kph). There have been
similar competitions held for solar-powered boats and other vehicles.
3. Geothermal energy is energy that emits from the earth. It comes
from magma and the radioactive decay of uranium, thorium, and
potassium. Magma is hot because of the tremendous amount of
friction and pressure to be found in the earth's subsurface area.

Geothermal energy, while massive in total, doesn't do too well when
compared to the amount of energy we get from the sun, which wins


by a factor of about 20,000. Nevertheless, geothermal energy is
tapped by over 20 countries, most notably Iceland, which gets 17%
of its electricity from geothermal energy. The largest geothermal
energy plants output a couple hundred MW (megawatts). It has been
estimated that Iceland has enough geothermal energy to provide 1700
MW for over 100 years.
The process of extracting power from the heat in the earth is pretty
simple. You pump water through pipes to the source of the heat and
let it boil, the stream runs a turbine which gathers power, then the
water is recondensed and sent through the cycle again. If we had
pipes strong enough and deep enough, we could send them down to
the earth's mantle and have a practically inexhaustible source of
electricity. But with today's technology, we can only reach pockets of
heat that are close to the surface.
Geothermal energy is not a strictly renewable energy source like
wind or hydro, because the ground cools down slowly as energy is
extracted from it. Nevertheless, geothermal energy does slowly
renew thanks to radioactive heating. It is thought that molten rock at
temperatures between 1,200 and 2,200°F (650 to 1,200°C) can be
found in pockets 50 to 60 miles (about 80 to 97 km) underneath the
earth's surface, just beneath the tectonic plates. This would provide a
prodigious source of geothermal energy, but the deepest hole
mankind has drilled only extends about 8 miles (13 km) down. As we
move towards independence from fossil fuels, geothermal will join
solar and nuclear energy in providing clean power to the world's
offices, industries, and homes.

4. A wind farm is a collection of windmills or turbines which are
used to generate electrical power through their mechanical motions
as they are pushed by the wind. Both Europe and the United States
have large numbers of wind farms, and the technology is also found
on other continents. In Asia, India especially has devoted a great deal
of funding to establishing wind farms. The energy generated by a


wind farm can be fed directly into the general energy grid after
passing through transformers.
As a potentially large source of renewable energy, wind farms are
particularly popular in nations which are focusing on alternative
energy. Other types of renewable energy include wave power and
solar arrays. All of these technologies take advantage of already
existing energy, converting it into a usable form. Since a wind farm
does not actively deplete resources as it generates power, it is
considered a form of “green” energy.
Naturally, some resources must be expended to create a wind farm.
The turbines, transformers, and grid system on a wind farm are often
made from less than ideal substances, such as metals mined in an
unclean way. However, once installed, a wind farm requires no
additional energy output other than that required for basic
maintenance. This is a marked contrast to a power plant which relies
on coal or petroleum products. Consumers who want to support wind
farms can buy energy credits which go to developers of wind farms.
Naturally, the best place for a wind farm is a windy location. In some
instances, a windy location may also be generally unusable or
uninhabitable. In other instances, a wind farm may take up useful
real estate which could be used for farming. This has led to some
criticism of wind farms, since they take up a great deal more space

than a comparable non-renewable energy generating facility. In
addition, wind farms pose a severe threat to migratory birds, as has
been clearly documented by several scientific organizations.
5. Hydropower utilizes different forces that are created by moving
water in order to generate power for a number of purposes. It is also
referred to as hydroelectric power, or simply as water power.
Hydropower can be used to generate electric power or also to create
mechanical motion that runs machines for a variety of needs. Unlike


many other sources of energy, such as fossil fuels, water power
supplies a constant source of energy that cannot be depleted.
There are different types of naturally occurring motions of water that
can be used for hydropower. The main occurrence is water that flows
along a river, or down waterfalls, where the force from the water
flowing from a higher place to a lower place is used to generate
power. Much research is taking place that explores the use of waves
and tides as another source for hydroelectric power. For example, a
gyroscope floating on waves can be used to drive pistons with the
rise and fall of water levels, or other devices can utilize the waves to
compress air, which then moves a turbine to produce energy.
Rivers were first used for water power, where wheels were designed
to turn from the force of the water in order to operate mills and
various types of machinery. Dams, mainly used to produce
electricity, are often built alongside other types of power plants, and
can be used to regulate the amount of water that flows through them
to produce different amounts of power. It is not completely necessary
to build a dam for this type of hydropower, and damless hydro
plants, as they are referred to, will usually utilize a smaller portion of
a river or stream.

There are many sources of hydropower that have yet to be developed
throughout the world, especially as other sources of energy become
depleted. While more environmentally friendly than other sources,
hydropower is not without its issues. Dams can have a negative
impact on surrounding ecosystems, such as lower populations of fish
as well as a reduction in the quality of the water itself. Because of
this, hydropower plants must be built with the environment in mind,
with safeguards to restore any losses that they may incur, along with
constant monitoring of environmental impacts.
6. Tidal and Wave energy is power generated from ocean tides. As
ocean tides are created by the moon's gravitational pull, they generate


energy. People may harvest this energy, and even create more,
through the use of sizable underwater turbines, or tide generators, in
oceanic areas known for high tidal movements. These turbines are
very similar to wind turbines, though they are much stronger, as
water is much denser than air.
During high tide, ocean water can be collected behind a barrage, and
then released as the tide ebbs. As the water is dispensed, it passes
through the turbine. By harnessing the kinetic energy of both high
and low tides in the turbine, electricity can be produced. By
eliminating the need for other sources of electricity that may produce
a heavy environmental impact, tidal renewable energy is considered
an effective form of alternative energy.
In addition to barrages, tidal fences may be used to collect wave
energy. Composed of vertical axis turbines mounted onto a fence,
they allow water to pass through, and direct it into turbines for use.
The use of tidal fences is generally ideal in areas where the fence
may connect two separate landmasses.