The document discusses the history of alternative energies and provides examples of alternatives that have been used throughout history to replace dominant energy sources. It notes that coal was used as an alternative to wood in Europe in the 1500s due to deforestation. In the 19th century, petroleum replaced whale oil as the dominant lubricant and fuel after whale stocks were depleted. More recently, alternatives like solar, wind, geothermal, biofuels and nuclear energy have been developed and advocated as replacements for fossil fuels to address concerns about sustainability and climate change. The document provides overview information on common alternative energy types as well as emerging concepts.

1. Alternative sources of energy
Made by:- Rohan ,saraswati ,Shiv shakti ,Sahil
and saluja
Class:- X C
Assignment of English

2. Alternative energy is any energy source that is an
alternative to fossil fuel. These alternatives are intended
to address concerns about such fossil fuels.
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3. History
Historians of economies have examined the key
transitions to alternative energies and regard the
transitions as pivotal in bringing about significant
economic change. Prior to the shift to an
alternative energy, supplies of the dominant energy
type became erratic, accompanied by rapid
increases in energy prices.
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4. Coal as an alternative to wood
"Europeans had lived in the midst of vast forests throughout
the earlier medieval centuries. After 1250 they became so
skilled at deforestation that by 1500 AD they were running
short of wood for heating and cooking... By 1500 Europe was
on the edge of a fuel and nutritional disaster, from which it
was saved in the sixteenth century only by the burning of soft
coal and the cultivation of potatoes and maize. "
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5. Petroleum as an alternative to
whale oil
Whale oil was the dominant form of lubrication and
fuel for lamps in the early 19th century, but
the depletion of the whale stocks by mid century
caused whale oil prices to skyrocket setting the stage
for the adoption of petroleum which was first
commercialized in Pennsylvania in 1859.
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6. Alcohol as an alternative to fossil
fuels
In 1917, Alexander GrahamBell advocated ethanol from corn,
wheat and other foods as an alternative to coal and oil, stating that
the world was in measurable distance of depleting these fuels. For
Bell, the problem requiring an alternative was lack of renewability
of orthodox energy sources. Since the 1970s, Brazil has had an
ethanolfuel program which has allowed the country to become the
world's second largest producer of ethanol and the world's largest
exporter.
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7. Coal gasification as an alternative
to petroleum
In the 1970s, President Jimmy Carter's administration
advocated coal gasification as an alternative to
expensive imported oil. The program, including
the Synthetic Fuels Corporation was scrapped when
petroleum prices plummeted in the 1980s. The carbon
footprint and environmental impact of coal gasification
are both very high.
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8. Common types of alternative
energy
Solar energy
Wind energy
Geothermal energy
Biofuel and Ethanol
Nuclear binding energy and Hydrogen
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9. Solar energy
Solar energy, radiant light and heat from the sun, is
harnessed using a range of ever-evolving
technologies such as solar heating, solar
photovoltaics, solar thermal electricity, solar
architecture and artificial photosynthesis.
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10. Wind power
Wind power is the conversion of wind energy into
a useful form of energy, such as using wind
turbines to make electrical power, windmills for
mechanical power, windpumps for water
pumping or drainage, or sails to propel ships.
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11. Geothermal energy
Geothermal energy is thermal energy generated 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 (80%).
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12. Biofuel and Ethanol
A biofuel is a fuel that contains energy from
geologically recent carbon fixation. These fuels are
produced from living organisms.Ethanol also
called ethyl alcohol , pure alcohol, beverage alcohol is
avolatile, flammable, colorless liquid with the structural
formula CH3CH2OH.
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13. Nuclear binding energy
Nuclear binding energy is the energy required to split
a nucleus of an atom into its component parts. The
component parts are neutrons and protons, which are
collectively called nucleons. The binding energy of nuclei
is always a positive number, since all nuclei require net
energy to separate them into individual protons and
neutrons.
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14. Hydrogen
Hydrogen is a chemical element with chemical
symbol H and atomic number 1. With an atomic
weight of 1.00794 u, hydrogen is the lightest element
on the periodic table. Its monatomic form (H) is
the most abundant chemical substance in the universe,
constituting roughly 75% of all baryonic mass.
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15. Enabling technologies
Heat pumps and Thermal energy storage are technologies
which use energy sources that normally can't be
obtained. Also, heat pumps have the advantage of
leveraging electrical power (or in some cases mechanical
or thermal power) by using it to extract additional energy
from a low quality source (such as sea or lake water, the
ground or the air).
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16. Renewable energy vs non-renewable
energy
Renewable energy is generated from natural resources—such
as sunlight, wind, rain, tides and geothermal heat—which are
renewable. When comparing the processes for producing
energy, there remain several fundamental differences between
renewable energy and fossil fuels. The process of producing oil,
coal, or natural gas fuel is a difficult and demanding process that
requires a great deal of complex equipment, physical and
chemical processes.
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17. Ecologically friendly alternatives
Renewable energy sources such as biomass are sometimes
regarded as an alternative to ecologically harmful fossil
fuels. Renewables are not inherently alternative energies
for this purpose. For example, the Netherlands, once leader
in use of palm oil as a biofuel, has suspended all subsidies
for palm oil due to the scientific evidence that their use
"may sometimes create more environmental harm than
fossil fuels"
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18. Relatively new concepts for alternative
energy
Carbon-neutral and negative fuels
Carbon-neutral fuels are synthetic fuels produced
by hydrogenating waste carbon dioxide recycled
from power plant flue-gas emissions, recovered from
automotive exhaust gas. Commercial fuel synthesis
companies suggest they can produce synthetic fuels for
less than petroleum fuels when oil costs more than $55
per barrel.
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19. Algae fuel
Algae fuel is a biofuel which is derived from algae. During
photosynthesis, algae and other photosynthetic organisms
capture carbon dioxide and sunlight and convert it into oxygen
and biomass. The benefits of algal biofuel are that it can be
produced industrially, thereby obviating the use of arable land
and food crops and that it has a very high oil yield as compared
to all other sources of biofuel.
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20. Biomass briquettes
Biomass briquettes are being developed in the
developing world as an alternative to charcoal. The
technique involves the conversion of almost any plant
matter into compressed briquettes that typically have
about 70% the calorific value of charcoal.
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21. Biogas digestion
Biogas digestion deals with harnessing the methane gas
that is released when waste breaks down. This gas can be
retrieved from garbage or sewage systems. Biogas digesters
are used to process methane gas by having bacteria break
down biomass in an anaerobic environment. The methane
gas that is collected and refined can be used as an energy
source for various products.
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22. Biological hydrogen production
Hydrogen gas is a completely clean burning fuel; its
only by-product is water. It also contains relatively high
amount of energy compared with other fuels due to its
chemical structure.
2H2 + O2 → 2H2O + High Energy
High Energy + 2H2O → 2H2 + O2
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