2. • Surface water because of its potential energy in certain areas, provides the cheapest, neat and clean
Dr. Rajendra Singh Thakur 2
resource of energy.
• Source of power has been serving human civilization since a earlier days from water wheel.
• Hydro electric power plant harnesses power from following under pressure (water fall from a height) .
• Electricity generator driven by water turbine represent water energy as electricity .
• Hydro power is not only a clean or non-polluting source but also a most conventional renewable
energy source.
• Further , with the limited sources of coal, lignite and oil, growing reliance would have to be placed on
hydel power.
• Except for the heavy initial investment, hydel projects have a definite edge over other power plants.
• This can be assessed by the fact that nearly 30% of the total power of the world is met by hydro-electric
power.
• The total hydro potential of the world is about 5000GW.
• World where almost entire power generation-
• Norway=99%
• South Africa= 75%
• Leading countries in production of hydro power are USA, USSR, Japan, Brazil etc.
3. • Hydro power is available in a range of sizes from a few hundred watts
to over 10GW.
• Micro-hydro systems operate by diverting part of the river flow through a
penstock (or pipe) and a turbine, which drives a generator to
produce electricity.
• Micro-hydro systems are mostly "run of the river" systems, which allow
the river flow to continue.
Dr. Rajendra Singh Thakur 3
4. SSiizzeess ooff HHyyddrrooppoowweerr PPllaannttss
Group 5
Pico HP - Up to 10kW, remote areas away from the grid
Dr. Rajendra Singh Thakur 4
Hydropower
More than 100 MW feeding into
a large electricity grid
15 - 100 MW
usually feeding a grid
Capacity above 1MW
Small HP
Micro HP
Large
Medium
HP
Mini HP
Capacity 300kW to
1MW
Capacity 0kW
to 300kW
7. • The basic components can be briefly described:
• Intake: This is where the water from the river/spring is diverted from its main course (River).
• Penstock: This is the pipeline supplying water from the fore bay to the turbine. It should be
well supported every 15 - 20 feet for Mild Steel / Cast Iron Pipes or be buried under a thin
layer of soil to protect it from physical damage and also from corrosion. The pipeline can be of
PVC too depending on the site conditions.
• Turbine: This is the mechanical device that rotates when driven by water issuing from pipes.
There are several kinds of turbines that can be used, e.g. Pelton wheel, cross flow turbines,
pumps as turbines and standard reaction turbines. Each kind of site is suited to a particular kind of
turbine. Therefore the choice of turbine is site-specific.
• Generator: Electricity is generated when the turbine drives the generator. There are basically
two kinds of generators that can be used for AC power. Regular Synchronous Generators are
the simplest option, but in the lower ranges of power (<10kW) it may be difficult to source them. In
this case, three phase induction motors can be used in reverse as generators with the help of a
capacitor bank.
• Distribution System: The electricity generated in the power house is supplied to the house holds
through local grids. This consists of weather proof Aluminium cables as conductors and locally
available wooden poles as electric posts.
Dr. Rajendra Singh Thakur 7
8. FFoorrmmss OOff HHyyddrrooppoowweerr
which
captures the
kinetic energy
from marine
currents.
Group 5
Dr. Rajendra Singh Thakur 8
Hydropower
Tidal
power
which
captures
energy from
the tides in
horizontal
direction
Wave
power Osmotic
power
Marine
current
power
which uses
the energy
in waves
which channels
river water into a
container separated
from sea water by a
semipermeable
membrane.
Ocean thermal
energy conversion -
which exploits the
temperature
difference between
deep and shallow
waters.
9. b) Energy from the sea
Energy from the sea is obtained in three different forms. They are Tidal energy,
Sea wave energy and Ocean thermal energy.
i) Tidal energy :-
The periodic rise and fall of sea level due to gravitational attraction of the moon
causes tides. A dam is constructed at a narrow opening between the land and
sea. The movement of water during high tide and low tide can be used to rotate
the turbines of generators to produce electricity.
ii) Sea wave energy :-
When strong wind blows over the sea it produces huge waves. The kinetic
energy of the moving waves can be used to rotate the turbines of generators to
produce electricity.
iii) Ocean thermal energy :-
There is a temperature difference between the warm surface water and the cold
water at the bottom of the oceans. This difference is about 20°C. The warm
surface water is used to boil liquid ammonia and the vapour is used to rotate
the turbines of generators to produce electricity. The cold water from the
bottom is then pumped up to cool the vapour back to liquid.
Dr. Rajendra Singh Thakur 9
13. • Potential in India
• India is blessed with immense amount of hydro-electric potential and ranks 5th in terms of exploitable
hydro-potential on global scenario. India is endowed with economically exploitable hydro-power potential to
the tune of 1,48 ,700 MW of installed capacity.
• The basin wise assessed potential is as under :-
Basin/Rivers Probable Installed Capacity (MW)
Indus Basin 33,832
Ganga Basin 20,711
Central Indian River system 4,152
Western Flowing Rivers of southern India 9,430
Eastern Flowing Rivers of southern India 14,511
Brahmaputra Basin 66,065
Total 1,48,701
• At present about 26% (36878 MW) of the country electricity is being generated through hydro power.
• Annual hydro electricity potential about 60% and load factor about 26%.
• About 80% developed in Maharastra, Tamil Naddu, Karnataka, Karala, Punjab, Himachal, Jammu
Dr. Rajendra Singh Thakur 13
Kashmir, Western UP (Uttrakhabd).
• In addition, 56 number of pumped storage projects have also been identified with probable installed
capacity of 94 000 MW.
• In addition to this, hydro-potential from small, mini & micro schemes has been estimated as 6,782 MW from
1,512 sites.
• Thus, in totality India is endowed with hydro-potential of about 2,50,000 MW.
14. Dr. Rajendra Singh Thakur 14
ADVANTAGES
• Once the dam is built, the energy is virtually free.
• No waste or pollution produced.
• Much more reliable than wind, solar or wave power.
• Water can be stored above the dam ready to cope with peaks in demand.
• Hydro-electric power stations can increase to full power very quickly, unlike other
power stations.
• Electricity can be generated constantly.
DISADVANTAGES
• The dams are very expensive to build. However, many dams are also used for
flood control or irrigation, so building costs can be shared.
• Building a large dam will flood a very large area upstream, causing problems
for animals that used to live there.
• Finding a suitable site can be difficult - the impact on residents and the
environment may be unacceptable.
• Water quality and quantity downstream can be affected, which can have an impact
on plant life.
15. The worldwide installed capacity of wind power reached 197 GW by the end of 2010.
China (44,733 MW), US (40,180 MW), Germany (27,215 MW) and Spain (20,676 MW) are
Dr. Rajendra Singh Thakur 15
ahead of India in fifth position.
In India, the wind power potential has been estimated at 45000 MW.
Today, power generation from wind contribution to bridging the gap between the supply and
demand for power.
The present installed capacity of 1080 MW of wind power represents a little more than 1% of
the total installed capacity in the country.
As such, 860 MW of wind power capacity was added during the Eighth Plan period as against
the initial target of 100 MW.
Potential windy locations have been identified in the flat coastal terrain of southern Tamil
Nadu, Kerala, Gujarat, Lakshadweep, Andaman & Nicobar Islands, Orissa and
Maharashtra.
Favourable sites have also been identified in some inland areas of Karnataka, Andhra
Pradesh, Madhya Pradesh, West Bengal, Uttar Pradesh and Rajasthan.
Locations having an annual mean wind power density greater than 150 watts per sq metre
at 30 metre height will be considered suitable for wind power projects. There are 177
locations identified so far with an aggregate potential capacity of about 5500 MW in 13
states.
16. • The Scheme- Wind turbines convert the wind’s kinetic energy into mechanical power.
• Wind Turbines- like aircraft propeller blades, turn in the moving air and power an electric generator
Dr. Rajendra Singh Thakur 16
that supplies an electric current.
• Wind Turbine Types- Modern wind turbines fall into two basic groups;
(1) the horizontal-axis variety, like the traditional farm windmills used for pumping water, and
(2) the vertical-axis design, like the Savonous rotor, Durrieus rotor, named after its French inventor.
Most large modern wind turbines are horizontal-axis turbines.
• Turbine Components- Horizontal turbine components include:
• a blade or rotor, which converts the energy in the wind to rotational shaft energy;
• a drive train, usually including a gearbox and a generator;
• a tower that supports the rotor and drive train; and
• other equipment, including controls, electrical cables, ground support equipment, and interconnection
equipment.
• More than 80% of the global wind energy capacity is installed in 5 countries with India at the 5th
position.
19. • The development of wind power in India began in the 1990s, and has significantly increased in the last few
Dr. Rajendra Singh Thakur 19
years.
• Although a relative newcomer to the wind industry compared with Denmark or the United States, India has
the fifth largest installed wind power capacity in the world.
• In 2009-10 India's growth rate was highest among the other top four countries.
• As of 31 Jan 2013 the installed capacity of wind power in India was 19661.15 MW, mainly spread across-
Tamil Nadu (7154 MW),
Gujarat (3,093 MW),
Maharashtra (2976 MW),
Karnataka(2113 MW),
Rajasthan (2355 MW),
Madhya Pradesh (386 MW),
Andhra Pradesh (435 MW),
Kerala (35.1 MW),
Orissa (2MW),
West Bengal (1.1 MW) and
other states (3.20 MW).
20. • It is estimated that 6,000 MW of additional wind power capacity will be
Dr. Rajendra Singh Thakur 20
installed in India by 2014.
• Wind power accounts for 8.5% of India's total installed power capacity, and it
generates 1.6% of the country's power.
• Wind energy potential in India have averaged 3 lakh MW against the prevailing
45,000 MW.
• The World Institutes study in Tamil Nadu indicated that just on wasteland alone
over 35,000 MW of wind power generation could be established against 6,000 MW
in place.
• In renewable energy sector, wind energy is commercially viable and can support
the Central Government target of setting up 60,000 MW of renewable energy
capacity by 2020 to get 15 per cent of the total electricity generation from clean
technologies.
• The Ministry of New and Renewable Energy (MNRE) has fixed a target of 10,500
MW between 2007–12, but an additional generation capacity of only about 6,000
MW might be available for commercial use by 2012.
24. Advantages
• Wind is free, wind farms need no fuel.
• Produces no waste or greenhouse gases.
• The land beneath can usually still be used for farming.
• Wind farms can be tourist attractions.
• A good method of supplying energy to remote areas.
Disadvantages
• The wind is not always predictable - some days have no wind.
• Suitable areas for wind farms are often near the coast, where land is
expensive.
• Can kill birds - migrating flocks tend to like strong winds.
• Can be noisy.
• See the graphic on the right. In this example, at the distance the turbine is
from houses, it makes less noise than your fridge
Dr. Rajendra Singh Thakur 24
26. • Geo (Earth), thermal (heat) energy is an enormous, reliable and stored in the Earth.
• Thermal energy is the energy that determines the temperature of matter.
• The geothermal energy of the Earth's crust originates from the original formation of the planet (20%) and
from radioactive decay of minerals (e.g. the uranium, thorium, and potassium content of rocks like
granite), (80%).
• At the core of the Earth, thermal energy is created by radioactive decay and temperatures may reach over
Dr. Rajendra Singh Thakur 26
5000 °C.
• Heat conducts from the core to surrounding cooler rock.
• The high temperature and pressure cause some rock to melt, creating magma convection upward since
it is lighter than the solid rock.
• The magma heats rock and water in the crust, sometimes up to 370 °C.
• Geothermal energy has been used for natural steam, space heating, ground water heat pumps,
recreational and health spas, agriculture growth enhancement, agriculture drying, industrial drying.
but it is now hot water or dry rocks used for power generation better known for electricity generation.
• Earth's energy can be converted into heat and electricity.
• Worldwide, 11,400 megawatts (MW) of geothermal power is online in 24 countries in 2012.
• The three technology categories are geothermal heat pumps, direct-use applications, and power
plants..
28. There are three geothermal power plant technologies being used to convert hydrothermal fluids to electricity.
1. Hydrothermal fluids – Hot water, Steam, Associate gases & Minerals.
The type of conversion used depends on the state of the fluid (whether steam or water) and its temperature.
Drilled to depth: 3km
Temperature: 300 °C.
Fluid depends: temperature, mineral composition & concentration and end uses.
2. Geo-pressure brines- hot water existing of pressure above the normal hydrostatic gradient & containing
dissolved methane are termed Geo-pressure brines.
Drilled to depth: 3km
Useful energy – kinetically energy, Thermal energy, natural gas convert of deep, high pressure of water wells
3. Hot dry rock- water free impermeable rocks at high temperature & at practical drilling depth.
First commercial geothermal electric power was at Larderllo in Italy 1904.
Generating worldwide capacity = 600 MW In 18-20 country.
The Geysers steam field near San Francisco (USA) having electric output about 2000 MW by 22 operating units and
other are California, Hawaii, Neweda, and Utah.
USA is now geothermal electric power generating capacity exceed 3000 MW
Other Philippines = 900 MW
Mexico = 700 MW
Italy = 550 MW
New Zeeland = 300 MW
Japan = 200 MW
Iceland = 40 MW
And few other
Dr. Rajendra Singh Thakur 28
29. • Geothermal energy with more than 340 hot water springs with average temp. 80-100°C.
• 5KW Geothermal pilot power plant at Manikaran at Himachal Pradesh.
• Thermax is planning to set up a 4-5 MW pilot project in Puga Valley, Ladakh (J& K)..
• Space heating and green house effect has been estimated at Puga. 62.5 m3 heated with
geothermal water achieved temperature 20°C.
• Mushroom cultivation & poultry farming implemented at RRL Jammu.
• 7.5 Ton capacity cold storage plant based ammonia absorption Manikaran utilized
Dr. Rajendra Singh Thakur 29
geothermal water following 90°C.
• India has the potential geothermal provinces can produce 10,600 MW of power.
• Though India has been one of the earliest countries to begin geothermal projects way back
in the 1970s, but at present there are no operational geothermal plants in India.
• India’s Gujarat state is drafting a policy to promote geothermal energy
31. • Potential Sites
i) Puga Valley (J&K)
ii) Tatapani (Chhattisgarh)
iii) Godavari Basin Manikaran (Himachal Pradesh)
iv) Bakreshwar (West Bengal)
v) Tuwa (Gujarat)
vi) Unai (Maharashtra)
vii) Jalgaon (Maharashtra)
Dr. Rajendra Singh Thakur 31
32. Most versatile and least pollution.
Relative inexpensive.
Modern emission control.
The power generation level is
higher for geothermal than for
solar and wind.
Can be used effectively and
efficiently for direct uses such as
space heating, geothermal heat
pump (GHP), hot water bath
resorts, aquaculture, green
houses, industrial processes and
enhanced oil recovery.
Drilling operation cause noise
pollution
Hot spots are sparsely
distribution, distance.
Minimum temperature 100°C.
Efficiency of power production low
(15%) as compare to fossil fuel
(35-40%).
Air pollution results H2S, NH3,
CO2
Dr. Rajendra Singh Thakur 32
33. BIOMASS ENERGY
The waste materials and dead parts of living things are called biomass.
Eg :- wood, animal dung, vegetable waste, agricultural waste, sewage etc.
Biomass is decomposed by anaerobic microorganisms to produce biogas.
Biogas is a mixture of gases containing methane, carbon dioxide, hydrogen
and hydrogen sulphide.
Biogas plant :-
The biogas plant has a large underground tank made of bricks and cement.
The lower part is the digester and the upper part has a dome with a gas outlet.
One side of the tank above the ground is a mixing tank and on the other side is
an overflow tank.
Animal dung is mixed with water in the mixing tank and the slurry is sent into the
digester. In the digester the slurry is decomposed by anaerobic microorganisms
and after a few days biogas is produced.
The gas is taken out through the gas outlet and used for heating and lighting
purposes. The slurry left behind is rich in nitrogen and phosphorus and is used
as manure for crops.
Dr. Rajendra Singh Thakur 33
35. • It is colorless and odorless and most efficient when used in a fuel cell.
• It is highly combustible and thus can be utilized as source of energy.
• Normal state of pure hydrogen is hydrogen molecule (H2) which is lightest of all gases.
• In atmosphere-
Very low level (0.1ppm).
Stable under normal condition.
But undergoes variation at elevated temperatures.
It forms compound with almost every other elements.
It is important industrial commodities- used in production
• Ammonia, urea, methanol
• Other higher alcohol, HCL etc.
• De-sulphurize or Hydrogenate.
• Various petroleum & edible oils
• Hydrogen is an efficient, renewable and clean or non-polluting fuel.
• Mixed with O2 provide
• Hydrogen = 29000 calories/gm
• Gasoline = 11200 calories/gm
• Coal = 7800 calories/gm
• Upon combustion it return to water, accompanied by virtually no pollution and no green house gas
production. If the technical and economical problem related with production, storage, transmission,
utilization and safety aspect are solved be largest beneficially.
Dr. Rajendra Singh Thakur 35
38. 1. Breaking down Hydrocarbons - mainly methane-
Breaking down HC, if oil or gases (fossil fuel) are
used to produce hydrogen energy.
Dr. Rajendra Singh Thakur 38
39. 2. Electrolysis from Water - process of splitting water in to
O2 and H2 using electrolysis consume large amount of energy.
Calculate - 1 Joule of H2 produce to 1.4 Joule of electricity.
Dr. Rajendra Singh Thakur 39
40. 3. By reacting water with metals – produced by
reacting water with metals such as sodium, potassium, boron, the
chemical by product during the process sodium oxide, potassium
oxide, boron oxide.
Dr. Rajendra Singh Thakur 40
41. • Bio-photolysis – production of hydrogen from splitting water with
sunlight is called Bio-photolysis .
• Biomass and waste streams can in principle be converted into biohydrogen
with biomass gasification, steam reforming, or biological conversion like
biocatalysed electrolysis or fermentative hydrogen production.
• The action of light on a biological system that results in the dissociation of a
substrate, usually water, to produce hydrogen. Related category.
• Microalgae and Cynobacteria metabolized in nitrogen.
• Algae-
Chlorella,
Scenedesmus,
Chalamydomonas,
Ankistrodemus,
Corralina and
Porphyridium evolve hydrogen.
Dr. Rajendra Singh Thakur 41
43. MERITS
• Colorless and odorless and non polluting
• Lightest chemical element and best energy to weight ratio of any fuel.
• Produce anywhere it can be produced domestically from decomposing of
water.
LIMITATIONS
• Other than some volcanic emanation, H2 doesn't exist in pure form in environment
because react so strongly with O2 and other elements.
• Difficult to handle, store and transport.
• Impossible to obtain H2 gas without expending energy in process.
• Ex.- production of H2 by-
Breaking down of HC
Electrolysis from water
Reacting water with metal
Dr. Rajendra Singh Thakur 43
44. • Energy released during a nuclear reaction in accordance with the mass-energy
equation is called nuclear energy.
• Equation E=mc2. by Albert Einstein developed a theory, in 1905 , Where
E = energy obtained by conversion of certain amount of matter into energy,
c2 = squire of the speed of light in cm/sec. and
m = lost mass that converted into energy called “Binding Energy”,
• The binding energy keeps the nucleus of every atom from flying apart.
• Binding energy, when released slowly and under control, produces heat that
power steam-driven electric generators in nuclear power plants.
• Nuclear or atomic energy is the most powerful kind of energy.
• A small quantity of radioactive material can produce an enormous amount of
Dr. Rajendra Singh Thakur 44
energy.
• Ur 1kg = 3 million tons of coal or 12 million barrel of oil.
46. • Production of electricity (nuclear fission) accounts for about
20% of world electricity generation.
• World first nuclear power plant design mainly electricity
production in 1957 at Calder Hall in Cumberland District., UK.
• At present 300 atomic power plant parting all over world.
• First position in USA in maximum-83,
• USSR-40,
• UK-35,
• France-34,
• Japan-25,
• Germany-15,
• Canada-13.
Dr. Rajendra Singh Thakur 46
47. • Tata institute of fundamental research (TIFR)- Bombay in 1945 under Dr. Homi Bhabha.
• Purpose including- Production of cheap electricity
Utilize nuclear techniques in – Agriculture, Industrial, Medicine, & others
• First nuclear power plant in India- Tarapur in Thana District, Mumbai in October1969.
• Total capacity of India =3360MW (cover total power generation about 2.6%).
• A parting atomic power station -
Tarapur = 2reactor of Boiling Water Reactor (BWR) type
Rawatbhata = 2 Pressurized Heavy Water Reactor (PHWR)
Kalpakkam = 2Pressurized Heavy Water Reactor (PHWR)
Narora = 2Pressurized Heavy Water Reactor (PHWR)
Kakrapara = 2Pressurized Heavy Water Reactor (PHWR)
Kalpakkam in 1985 =One Fast Breeder Test Reactor (FBTR)-40MW Thermal (MEt) & 13MW Electrical
Dr. Rajendra Singh Thakur 47
(MWt)
Aditional 8 research reactor = 6 of Trombay & 2 of Kalpakkam
Department of Atomic Energy-1954
Atomic Energy Commission set up – 1948 for planning and formulation of atomic energy policy.
48. • This is a well-known way to produce electricity, since Rutherford was thinking about it, until
well-known events like World War II and Chernobyl.
• Nuclear fission uses heavy elements and after the fission the element is medium-seized.
• The fuel needed to produce this energy is Uranium and Plutonium isotopes.
• It requires just some atoms to make produce about 200 million electron volts.
• Nuclear fission is responsible for the invention of some elements such as Plutonium,
Neptunium and other chemical elements invented on the 20th century.
• Heavy atomic nucleus (U-235) splits into 2 approximately equal nuclei at same time emitted
neutrons and releasing very large amount of energy approximately 3x10-11 J or 220MeV.
• 1kg U-235 = 3 million tons of coal
• 1gm U-235 = 2.26x104 kWh used for generation electricity.
• CHAIN REACTION-
• U-235 (92 proton and 143 neutron) unstable nucleus is easily broken when hit by a neutrons
into two equal sized nuclei (krypton and barium) besides liberating a great deal of binding
energy results heat and several neutrons.
• created as basis of – Nuclear reactor &
Nuclear weapons
Dr. Rajendra Singh Thakur 48
52. • Light Atomic Nuclei fuse together to form single heavy nucleus with
release of large quantity of energy.
• The mass of single nucleus formed is less than total initial mass of
nuclei.
• Difference in mass is due to conversion of some mass into energy
according to Einstein’s equation E-mc2
• Ex. Fusion of two deuterium (1H2) Nuclei gives helium nucleus.
Dr. Rajendra Singh Thakur 52
1H2 + 1H2 = 2He4 +24MeV
• Which much less than energy produces in U-235 but energy
released/unit mass light nuclei much higher.
53. • Nuclear fusion is the union of two nucleuses that releases energy.
• This is the process that gives to the sun that big temperatures and so much
light; in general this spring of energy.
• Two different Hydrogen isotopes are united to produce Helium, release one
neutron and huge amount of energy; even more than nuclear fission.
• As far as nuclear fusion produces Helium, is absolutely friendly with the
environment and hydrogen is really easy to find, which makes it very cheap.
• Although, as this process is taking place to the sun, we can realise the
Dr. Rajendra Singh Thakur 53
temperatures it produces.
• Even worst, to start a new fusion chain reaction the temperature of the
elements environment, has to be some million Kelvin.
• Thus scientists can’t use controlled nuclear fusion as there is not any
existence of any material to cope with this temperature and there is a big
energy loss to start it.
• As everything else seems to be perfect, scientists have to find a solution for
this problem, so that energy crisis will be solved!
54. • Most of the energy is in the form of energetic neutrons
(charge neutral), as in deuterium-tritium reaction.
Dr. Rajendra Singh Thakur 54
56. • Most of the energy is carried by charged particles, by
positively charge proton.
• Energy might be used directly to drive an electric current,
without a steam rising cycle.
Dr. Rajendra Singh Thakur 56
58. Nuclear fusion and nuclear fission are two different types of energy-releasing reactions in which energy is released from high-powered
atomic bonds between the particles within the nucleus. The main difference between these two processes is that fission
is the splitting of an atom into two or more smaller ones while fusion is the fusing of two or more smaller atoms into a
larger one.
Nuclear Fission Nuclear Fusion
Definition: Fission is the splitting of a large atom into
two or more smaller ones.
Fusion is the fusing of two or more lighter
atoms into a larger one.
Natural occurrence of the process: Fission reaction does not normally occur
in nature.
Fusion occurs in stars, such as the sun.
Byproducts of the reaction: Fission produces many highly radioactive
particles.
Few radioactive particles are produced
by fusion reaction, but if a fission "trigger"
is used, radioactive particles will result
from that.
Conditions: Critical mass of the substance and high-speed
neutrons are required.
High density, high temperature
environment is required.
Energy Requirement: Takes little energy to split two atoms in a
fission reaction.
Extremely high energy is required to
bring two or more protons close enough
that nuclear forces overcome their
electrostatic repulsion.
Energy Released: The energy released by fission is a
million times greater than that released in
chemical reactions; but lower than the
energy released by nuclear fusion.
The energy released by fusion is three to
four times greater than the energy
released by fission.
Nuclear weapon: One class of nuclear weapon is a fission
Dr. Rajendra Singh Thakur 58
bomb, also known as an atomic
bomb or atom bomb.
One class of nuclear weapon is the
hydrogen bomb, which uses a fission
reaction to "trigger" a fusion reaction.