This document provides information on various renewable and inexhaustible energy sources including geothermal energy, tidal energy, and biomass. It discusses the origins and mechanisms of geothermal energy production from the Earth's core. It describes different types of geothermal power plants including dry steam, flash steam, and binary cycle plants. The document also outlines the working principles of tidal energy generation using tidal stream generators and tidal barrages. Finally, it discusses biomass energy production from waste conversion through gasification, pyrolysis, digestion, and fermentation and provides examples of past and current biomass energy projects.

1. 1
Shree Swami Atmanand Saraswati Institute
Of Technology
Biomass ,Tidal & Geothermal Energy
Sub.: Environmental StudieS
Prepared by :- Prof. Karm Balor
Year : 2015-16

2. Inexhaustible Energy
Source

3.  Geothermal Energy
 Tidal energy
 Biomass

4. •The word geothermal originated from the Greek
roots geo, meaning earth, and thermos, meaning heat.
• In simple means, Geothermal energy is thermal
energy generated and stored in the Earth.
*P.S.:
Thermal energy is the energy that determines
the temperature of matter
WHAT IS GEOTHERMAL ENERGY???

5. Origin of Geothermal Energy

6.  Initially, the energy transformed starts from way down t he
Earth’s core – 4,000 miles down. At the core, temperatures
may reach over 9,000 degrees Fahrenheit. Heat conducts
from the core to surrounding rock. Extremely high
temperature and pressure cause some rock to melt, which
is commonly known as magma.
 Magma convents upward since it is lighter than the solid
rock. This magma then heats rock and water in the crust,
sometimes up to 700 degrees Fahrenheit. This magma near
the Earth’s surface is what is used and transformed in
power-plants.

8. Direct Sources function by sending water
down a well to be heated by the Earth’s
warmth.
Then a heat pump is used to take the heat
from the underground water to the
substance that heats the house.
Then after the water it is cooled is injected
back into the Earth.

9. Air Conditioning Drying
Hot Water Springs
Greenhouses
Aquaculture

10. Dry Steam
Plant
Flash
Steam
Plant
Binary
Cycle Plant
Hot Dry
Rocks

11.  Dry Steam- Steam is produced directly from the
geothermal reservoir to run the turbines that power the
generator, and no separation is necessary because wells
only produce steam. The image below is a more simplified
version of the process.
 Flash Steam- Geothermally heated water under pressure
is separated in a surface vessel (called a steam separator)
into steam and hot water (called “brine” in the
accompanying image). The steam is delivered to the
turbine, and the turbine powers a generator. The liquid is
injected back into the reservoir.

12.  Binary Cycle- Known as binary geothermal plants, the
facilities that make this possible reduce geothermal
energy’s already low emission rate to zero. The
geothermal water (called “geothermal fluid” in the
accompanying image) heats another liquid, such as
isobutane or other organic fluids such as
pentafluoropropane, which boils at a lower temperature
than water. The two liquids are kept completely separate
through the use of a heat exchanger, which transfers the
heat energy from the geothermal water to the working
fluid. The secondary fluid expands into gaseous vapor.
The force of the expanding vapor, like steam, turns the
turbines that power the generators. All of the produced
geothermal water is injected back into the reservoir.

13. Flash/Binary Combined Cycle: This type of plant, which
uses a combination of flash and binary technology, has
been used effectively to take advantage of the benefits of
both technologies. In this type of plant, the portion of the
geothermal water which “flashes” to steam under reduced
pressure is first converted to electricity with a backpressure
steam turbine and the low-pressure steam exiting the
backpressure turbine is condensed in a binary system.

14. Homegrown Energy
Geothermal Heat Pumps
Low maintenance charge
Produces 4 times the energy that
they consume
Can be online 90-100% of the time
L ess gaseous emissions
Good Alternative to Fossil
Fuels
Electricity generated by
geothermal plants saves 83.3
million barrels of fuel each year
Direct use of geothermal
energy prevents 103.6 million
barrels of fuel each year
Positive Attributes

15.  Geothermal energy does not produce any pollution, and does not
contribute to the greenhouse effect.
 The power stations do not take up much room, so there is not
much impact on the environment.
 Geothermal energy generally involves low running costs since it
saves 80% costs over fossil fuels and no fuel is used to generate the
power.
 Dependence on fossil fuels decreases with the increase in the use
of geothermal energy. With the sky-rocketing prices of oil, many
countries are pushing companies to adopt these clean sources of
energy.
 Since ancient times, people having been using this source of
energy for taking bath, heating homes, preparing food and today
this is also used for direct heating of homes and offices.
 Geothermal energy on the other hand has created many jobs for
the local people.

16. Can
release
H2S
Can cause
Land
Subsiden
ce
Can
Salinate
Soil

17.  The big problem is that there are not many places where you
can build a geothermal power station. You need hot rocks of a
suitable type, at a depth where we can drill down to them. The
type of rock above is also important, it must be of a type that
we can easily drill through.
 Sometimes a geothermal site may "run out of steam", perhaps
for decades.
 Hazardous gases and minerals may come up from
underground, and can be difficult to safely dispose of.
 To get geothermal energy, requires installation of power plants,
to get steam from deep within the earth and this require huge
one time investment and require to hire a certified installer
and skilled staff needs to be recruited and relocated to plant
location. Moreover, electricity towers, stations need to set up
to move the power from geothermal plant to consumer.

19. Biomass is matter usually thought
of as garbage.
If garbage can be converted to
useful energy?
How biomass works is very simple.
Recycling biomass for fuel and
other
uses cuts down on the need for
"landfills" hold garbage.

20. Biomass is biological material derived from living, or recently
living organisms. In the context of biomass for energy this is
often used to mean plant based material, but biomass can
equally apply to both animal and vegetable derived material.
What is the Biomass ?
Biomass comes in a million physical forms
However, it is composed typically of
Cellulose - 50%
Hemi cellulose - 25%
Lignin - 25%
Most biomass can be represented by
CH1.4O0.6

21. The difference between the biomass and fossil fuel
The vital difference between biomass and fossil fuels is
one of time scale.
Biomass takes carbon out of the atmosphere while it is
growing, and returns it as it is burned. If it is managed on
a sustainable basis, biomass is harvested as part of a
constantly replenished crop. This is either during
woodland or arboricultural management or coppicing or
as part of a continuous programmer of replanting with the
new growth taking up CO2 from the atmosphere at the
same time as it is released by combustion of the previous
harvest.
This maintains a closed carbon cycle with no net increase
in atmospheric CO2 levels.

22. HOW WAS BIOMASS USED IN THE PAST?
Biomass was the first fuel mankind
learned to use for energy. Burning wood
for warmth and cooking and keeping wild
animals away
Some of the earliest power plants in
America were fueled by wood material
It was an abundant fuel in many parts of
the country where logging took place
It burned much cleaner than coal and it
was available before abundant oil and
natural gas was discovered
Many cultures used animal dung to burn,
and some are still doing this today
http://hearth.com/what/historyfire.html

23. CONVERSION OF BIOMASS WASTE INTO USEABLE FUEL
Gasification : Exposing a solid fuel to high
temperatures and limited oxygen
produces biogas.
Pyrolysis : Heating the biomass can
produce pyrolysis oil and phenol oil
leaving charcoal.
Digestion : Bacteria, in an oxygen-starved
environment can produce methane.
Fermentation : Bio-material that is used
to manufacture Ethanol and Biodiesel by
an anaerobic biological process in which
sugars are converted to alcohol by the
action of micro-organisms, usually yeast.
Solid Fuel Combustion : Direct
combustion of solid matter.
Biomass to Biogas

24.  Greenhouse gases produced by burning
 Extra costs of installing technology to process and
recycle wastes
 Expensive to collect, harvest and store raw materials
 Large scale crop production will use vast areas of land
and water, representing major problems

25. Biomass Advantages
• Biomass is very abundant. It can be found on every
square meter of the earth as seaweed, trees or dung.
• It is easy to convert to a high energy portable fuel
such as alcohol or gas.
• It is very low in sulphur reducing the production of
acid rain.
• Preservation of agricultural land that otherwise
would be sold for residential development or
industrial use = wide open spaces!!

26. Biomass production can often mean the restoration of waste
land (e.g. deforested areas).
• It may also use areas of unused agricultural land and
provide jobs in rural communities.
• Sustainable agricultural techniques for these crops can
restore and ensure soil stability and health along with
minimizing chemical residues and habitat destruction
• Today 10,000 megawatts (MW) in total biopower capacity
installed nationwide.

27. • Use of waste from agricultural and timber industries. An
estimated 350 million tons of waste that goes to landfills
could be used for energy production.
• Methane is 20 times more potent than CO2. Capturing
methane from producers such as cows or rice fields and
applying it for fuel will significantly reduce this greenhouse
gas.
• If it is produced on a renewable basis using biomass energy
does not result in a net carbon dioxide increase as plants
absorb it when they grow.

28. Biomass (Future) Advantages?
• Biomass can be used to produce solid, liquid, gaseous fuels as
well as electricity directly
• Fuel production technology is (largely) mature
• Combustion/conversion technology is immature
• Plants store energy at the rate of ~ 3000 EJ/yr, 2/3 on land
• Humans already manage around 1/2 of the usable land area
for food and fibre, and managed forests store ~ 600 EJ/yr.
Exa - 1018; Peta - 1015; Tera - 1012; Giga - 109; Mega - 106
1 TW = 31.54 EJ/year

30.  Rise and fall in sea levels
 Caused by the combined effect of
moon and sun.
 Tides are quite predictable.

31. WORKING PRINCIPLE:-
 Consists of a turbine & an electrical
generator(alternator).
 Turbines/windmill like blades are
installed on the ocean floor.
 Turbine and generator are connected
directly or by a gearbox.
 Due to kinetic or potential energy of
sea water the turbine rotates.
 Generator rotates and produces electricity
 At shore, electricity can be distributed.

32. Tidal
Generator
Tidal stream
generators
Tidal barrages
Dynamic tidal
generators

33.  It make use of kinetic energy
of moving water.
 It’s design is similar to
wind turbines but it’s
performance is better.

34. Requirement of
land.
Density
difference
predictability

35.  It make use of potential
energy of sea water.
 Difference in water level b/w
barrage & sea is used.
 It consist of turbine, sluice gate,
a basin to store water etc.
 During high tides the basin is
filled through sluice gate.

36.  DTP is an untried but
promising technology.
 an interaction between potential
and kinetic energies in tidal flows.
 Very long dams( 30–50 km length)
from coast to coast are needed.
 By this Tidal phase differences are
introduced across the dam.

37. Advantages:-
 Inexhaustible energy resource
 Most efficient energy source
 Predictability
 No green house gas emission
 Protect from dangerous tides
Disadvantages:-
 Ecological
 Corrosion
 High investment at start
 Can not produce electricity continuously

38.  Sihwa Lake Tidal Power Station(254MW) in South
Korea.
 Rance Tidal Power Station(240MW) in France.
 812 MW tidal barrage near Ganghwa Island (South
Korea) Completion is planned for 2015.
 A 1,320 MW barrage is proposed by the South Korean
government, with projected construction start in 2017.

39.  West Bengal Renewable Energy Development Agency
in sunderbans.
 The Indian state of Gujarat is planning to host South
Asia's first commercial-scale tidal power station. The
company Atlantis Resources is to install a 50MW tidal
farm in the Gulf of Kutch on India's west coast, with
construction starting early in 2012. later on it is
decided to increase the capacity up to 250MW plants.

40.  Situated near the breakwaters of Vizhinjam Port
which is about 20 km from Thiruvananthapuram city.
The station started its commercial operation in 1991.
This oscillating water column (OWC) produces about
150 kw of power.