2. Photovoltaic Devices Solar Thermal Electric Power Plant
Photovoltaic effect recognized The first application of solar thermal
In 1839 followed by the first in 1767 known as ‘hot box’, later in
photovoltaic cell in 1883. 1891 the first solar thermal system
was built.
Converts energy from the sun
directly into electricity Generate electricity indirectly
from the sun. Most commonly used -
Solar Power Tower, Parabolic Trough.
Used to power or recharge
portable devices and for Used in large electric power
residential commercial use. production and for residential
commercial use.
3.
4.
5. - Solar Panels are made up
of a collection of solar cells
that are then bonded to a
sheet of glass. It converts
sunlight into electricity
which can be used
immediately or stored in a
battery.
- Solar Cell is made of
semiconductors, like silicon,
that has special material
properties that allow the
sun light that strikes a cell
to be absorbed in the
material.
6. Charge controller - Also known as charge regulator, monitors
the battery's charge state.
- Protect the battery from
discharging, below its lowest acceptable
voltage, to prevent damage by over
discharge.
- Protects against wrong connection of the
battery and reverse voltage to the panel.
- Stores the power generated by the solar
Batteries modules during the day to be used
during the night.
- The type of battery used is Deep Cycle
(Lead Acid) Maintenance Free type.
- This battery is designed to be fully
charged and discharged over and over
again without causing damage.
7. DC-AC Inverter
- DC-AC inverters are used to convert Direct Current (DC) from
the battery into Alternating Current (AC) to run AC appliances.
- Types of inverters available are Stand-alone inverters,
Synchronous inverter and multi-function inverter
Stand-alone Inverter Synchronous Inverter Multi-function Inverter
10. Heliostat ~ Mirrors which reflects
the sun’s energy to the correct Central Receiver ~ Receives
spot on the tower. concentrated solar radiation
and transform it to thermal
power.
3
Molten Salt ~
Stores the sun's
2 heat and release it
1 in a controlled
manner for steady
SOLAR POWER TOWER steam turbine
power generation.
4
5
6
Condenser ~ Condense exhaust
steam from the steam turbine Turbine ~ Receives steam Storage Tanks ~ Stores fluid,
and channels it back to steam from steam generator that one at high temperature
generator. turns the turbine blades to and one at low temperature.
generate electricity.
11.
12. Collector ~ Structure of collector must :
- Supports the mirrors and receivers,
maintaining them in optical alignment
- Withstands external forces(winds).
- Allows the collector to rotate, so the 2
mirrors and receiver can track the sun.
1
Mirrors ~ Usually coated with
silver or polished aluminum.
6 Reflects the suns energy to the
receiver.
PARABOLIC TROUGH 3
Collector Interconnect ~
Connects the receivers on two
adjacent collectors and allows 4
them to track independently. Steel tube ~Surrounded
Drive ~ Positions the by a glass envelope to
5
collector to track the reduce convection heat
sun during the day. It losses. Functions as a
can be either a standard Fluid ~ Normally receiver that can
motor and gear box oil, absorbs accept optical input
configuration or can use sunlight, increases from any direction.
a hydraulic drive System. temperature
and heats steam in
13. P G
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14. Multiple solar or
The solar cells will
Converts energy photovoltaic cells
convert sunlight
from the sun are connected to
directly into
into electricity. form a solar
electricity (DC).
module.
It monitors the The role of the charge The electricity
condition of the controller is to from the solar
battery state of charge regulate the voltage cells is stored
and protects the and current from the in the battery
battery from being solar cells before it is for immediate
over-charged. stored in the battery. or later .
The charge controller
will also protect the Where required, an inverter
battery from is used to change the Direct
discharging below its Current (DC) to Alternating
lowest acceptable Current (AC) to power most
voltage. AC appliances.
19. 1. Greatly reduced 1. It is available most
pollution. abundantly in areas with a
2. Greatly reduced high number of sunshine
contribution to global hours.
warming. 2. It is not directly available at
night or under cloud cover.
3. Infinite energy
3. DC power must be
resource. converted to AC power
4. Reduced maintenance before it can be used.
costs. 4. Initial installation cost may
5. Falling production be too expensive.
costs. 5. Solar panels require large
6. Low running costs. land/roof areas to be
7. Local application. effective.
20. • With the threat of global warming, and the gradual depletion of petroleum supplies,
“Why we don't use more solar energy?”
1) The energy intensity of solar energy is relatively low.
2) The technology is expensive.
• Solar Thermal Vs Photovoltaic.
– Solar Thermal has an efficiency of 70% whereas PV 12%.
– Solar Thermal requires much less space than PV.
– Solar Thermal are 5 times cheaper than PV.
– Difficult to add thermal walls and other passive solar collectors to an
existing home which gives an advantage to PV.
– Solar thermal space heating system will sit idly by during the long summer
months while a solar PV system will provide usable electricity all year.
• Differences between Solar panels and Solar Modules :
– Technically, there is a difference, but even within the solar industry there is
no clear cut answer. For all practical purposes, a solar panel is the same as
a solar module.
21. • Solar power is a good alternative energy source. It does
not hurt the environment and it is a renewable energy
source.
• Can be used to power houses and their electronic
appliances, such as flashlights, electric motors and even
refrigerators. It can also be used to heat water and cool
buildings.
• Two ways to capture the suns energy, by Photovoltaic
devices and Solar Thermal Electric Power Plant.
• Learned how solar energy can be used to make
electricity and power everyday appliances.
• Also learned about structures of Photovoltaic
Panels, Solar Thermal and how it works.