Hydroelectric ?

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RE technology options

• Hydroelectric ?
• Solar ?
• Wind
• Geothermal
• Marine (Wave and Tidal)
• Biofuels (Biomass, Bioethanol and Biodiesel)

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Major Reference
Solar energy Trends and enabling technologies
(by V. Devabhaktuni, M. Alam, S.S.S.R. Depuru,
R.C. Green II, D. Nims, C. Near) Renewable and
Sustainable Energy Reviews, Vol. 19 (2013)
555564
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Average annual global solar energy
The earth receives a huge amount of energy in the
form of solar radiation. On average, it is
1,700 kWh/m2/year ( 194 W/m2) The total amount
received on the planets surface is equal to
approximately 10,000 times the global energy
consumption.
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Average annual global solar energy
7.5 7 6 5 4 3
Clear sky insolation, incident, horizontal
surface (kWh/m2/day)
Source NASA 2008
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Major solar energy conversion technologies
Solar Thermal (Solar T)
is a technology by which sunlight is used to
directly warm water or air without involving
electricity.
Concentrated Solar Power (CSP)
is a technology by which sunlight is focused by
mirrors or re?ective lenses to heat a ?uid in a
collector at high temperature.
Solar Photovoltaics (Solar PVs)
are arrays of cells containing a semiconductor
material that converts solar radiation into
direct current (DC) electricity.
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Major solar energy conversion technologies
Solar Thermal (Solar T)
is a technology by which sunlight is used to
directly warm water or air without involving
electricity.
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Solar Thermal Solar water heaters
Solar heating capacity was 185 GWh-thermal in
2011.
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Solar Thermal Solar water heaters

• Passive solar water heaters
• Active solar water heaters

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Solar Thermal Passive solar water heater
- It consists of an absorption mechanism. - The
absorption mechanism is typically some type of
copper tubing (in various configurations) that
are painted with a coating to improve efficiency.
- Water (or air) is sent through the absorption
piping system where it is heated.
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Solar Thermal Passive solar water heater
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Solar Thermal Active solar water heater

• It consists of the following
• - an absorption mechanism
• - a transfer mechanism
• - a storage tank

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Solar collector
Solar Thermal Active solar water heater
To taps
Controller
Tank
Boiler
Cold water feed
Pump
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Solar Thermal Active solar water heater
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Solar Thermal solar water heaters
Flat plate solar collection system
Evacuated tube solar collection system
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Major solar energy conversion technologies
Concentrated Solar Power (CSP)
is a technology by which sunlight is focused by
mirrors or re?ective lenses to heat a ?uid in a
collector at high temperature.
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Concentrated Solar Power (CSP)
In CSP systems, sunlight is focused by re?ective
lenses to heat a ?uid in a collector to high
temperatures.
I. Purohit, P. Purohit / Energy Policy 38 (2010)
30153029
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CSP for electricity generation Parabolic trough
http//www.greenrhinoenergy.com/solar/technologies
/cst_technologies.php
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CSP for electricity generation Parabolic trough
A solar parabolic trough is constructed as a long
parabolic mirror (usually coated silver or
polished aluminum) with a Dewar tube running its
length at the focal point.
Sunlight is reflected by the mirror and
concentrated on the Dewar tube. The fluid (eg.
Oil) running through the Dewar tube is therefore
heated up.
Source http//en.wikipedia.org/wiki/Parabolic_tro
ugh
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CSP for electricity generation Parabolic trough
The trough is usually aligned on a north-south
axis, and rotated to track the sun as it moves
across the sky each day.
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CSP for electricity generation Parabolic trough
Solar energy trapped by solar troughs heats the
thermal oil. Oil circulating in a closed loop
heats high volumes of water to generate steam at
high temperatures (up to 400oC). Steam turbine
generates electricity (at about 30 conversion
efficiency).
Source http//www.solarpanelsplus.com/parabolic-t
rough-collectors/
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CSP for electricity generation Parabolic trough
Solar Energy Generating Systems (SEGS) consists
of nine solar power plants (built between 1984
and 1990) in California's Mojave Desert, where
insolation is among the best available in the US.

• - 354 MW installed capacity
• power 232,500 homes
• have a total of 936,384 mirrors
• cover more than 1,600 acres (6.5 km2)
• lined up, the parabolic mirrors would extend
  over 370 km.
• 3000 broken mirrors (mostly by wind) per year
  are replaced

Source http//en.wikipedia.org/wiki/Solar_Energy_
Generating_Systems
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CSP for electricity generation Solar tower
http//www.abengoasolar.com/corp/web/en/technologi
es/concentrated_solar_power/power_tower/index.html
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CSP for electricity generation Solar tower
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CSP for electricity generation Solar tower

• - There is a central tower receiver surrounded by
  a field of mirrors (called heliostats)
• The mirrors (tracking the angle of the sun)
  concentrate the solar radiation onto a central
  heat absorber situated in the tower.
• The temperature of the fluid in the absorber on
  the tower can reach up to 500oC to 1000oC.
• The fluid is used to heat water and run the
  steam turbine that produces electricity.

http//www.greenrhinoenergy.com/solar/technologies
/cst_technologies.php
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CSP for electricity generation Solar tower
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CSP for electricity generation Solar tower
Solucar PS10 (in Spain) is a commercial solar
thermal power tower-based plant
http//en.wikipedia.org/wiki/Solar_power_tower
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CSP for electricity generation Solar tower
Facts on Solucar PS10

• - Solar tower is 115 m high, 40-story tower where
  a solar receiver and a steam turbine are located
• 624 movable mirrors (called heliostats) with 120
  m2 surface area each
• four years to build
• cost 35 million Euros
• 11 MW installed capacity

http//en.wikipedia.org/wiki/PS10_solar_power_towe
r
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CSP for electricity generation
If heat received could also be stored in a
thermal storage media, the parabolic-trough and
central tower CSP plants can reduce the effects
of solar intermittency by producing electricity
at night.

• Storage media used are
• pressurized steam
• concrete
• molten sodium nitrate
• molten potassium nitrate
• puri?ed graphite

http//www.greenrhinoenergy.com/solar/technologies
/cst_technologies.php