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1. 1. Examine the photovoltaic theory and its types of PV systems with a neat
diagram ?
Photovoltaic (PV) system is an electrical system
consisting of array of one or more PV modules,
conductors, electrical components, and one or
more loads which Convert solar radiation into
electricity.
PV systems use wafers, typically made of
crystalline silicon.
Other component are Inverter, charge
controller, batteries etc.
Solar Photovoltaic Systems:
Solar Photovoltaic (PV) systems convert solar energy
directly into electrical energy
The basic conversion device used is known as a solar
photovoltaic cell or a solar cell
A solar cell is basically an electrical current source,
driven by a flux of radiation. Solar cells were first
produced in 1954 and were rapidly developed to provide
power for space satellites
Efficient power utilization depends not only on efficient
generation in the cell, but also on the dynamic load
matching in the external circuit

2. Crystalline Materials
Single-crystal silicon
Polycrystalline silicon
Gallium Arsenide (GaAs)
Thin Film Materials
Amorphous Silicon (a-Si)
Cadmium Telluride (CdTe)
Copper Indium Diselenide (CuInSe2, or CIS)

3. PV cells are made of dissimilar materials (n
and p type silicon) which are in contact and
form a barrier at the junction.
When sunlight hits the cell, it creates a
electron and a hole pair at the junction.
Connecting both sides to an external circuit
the current will flow.
Types of PV Systems
Stand-alone system
it is independent of all sources & used in
remote applications.
Grid connected system
it is connected with grid and store its surplus
power into grid by concept of net metering.
Hybrid system
it receives a portion of its power from more
than one sources like wind generator or any
fuel fired generator

5. 2. Analyze the various characteristic curves of different MPPT
techniques.
When a solar PV system is deployed for practical
applications, the I-V characteristic keeps on changing
with insolation and temperature
In order to receive maximum power, the load must adjust
itself accordingly to track the maximum power point
The I-V characteristics of PV system along with some
common loads are shown in the next slide
An ideal load is one that tracks the maximum power

6. point
If the operating point departs significantly from the
maximum power point, it may be desirable to interpose
an electronic maximum power point tracker (MPPT)
between PV system and load

10. MPPT method can extract maximum available power from the PV
module.
This can increase the tracking efficiency.
If your energy use is greatest in the winter (typical in most homes) and
you have cold winter weather, then you can gain a substantial boost in
energy when you need it the most!
3. Examine the different applications of solar energy collectors with neat
diagrams and infer the principle of conversion of solar energy into heat.?

15. 4. With relevant sketches analyze the working operation and principle of a
geothermal power plant?

27. 5. Construct a Grid connected PV system with MPPT Controller and also
mention the factors to be considered in grid integration.
Grid-tied, On-grid, Utility-interactive, Grid Inter-tie And Grid Back Feeding
are all terms
used to describe the same concept – a solar system that is connected/
Synchronized to the
utility power grid.
Condition 1:
ELECTRICITY PRODUCED <= CONSUMPTION
All Solar Produced electricity is Consumed on
site and only differential electricity drawn from
Grid AC LOADS GRID.

28. Condition 2:
ELECTRICITY PRODUCED > CONSUMPTION
Excess Solar Power is exported to Grid
Through Bidirectional Meter.

30. Saves more money with net metering
Better efficiency rates
Lower equipment installation costs

31. No investment for purchase and maintenance of costly batteries
With NET METERING, consumer can put this excess electricity onto the
utility grid instead of storing
it in batteries.
Total life is 20-25 Years
2. The utility grid is a virtual battery
The electric power grid is in many ways also a battery, without the need for
maintenance or
replacements, and with much better efficiency rates.
6. Analyze the function of solar pumping and solar thermal power plants?
Basics of solar water pumping system
Parts of a solar water pumping system
● Solar PV panel
● One of the following motor-pump sets compatible with the photovoltaic
array:
○ surface mounted centrifugal pump set
○ submersible pump set
○ floating pump set
○ Submersible pump set
● Pipes

32. Working of a solar water pumping system
The system operates on power generated using solar PV (photovoltaic)
systems. The photovoltaic array converts the solar energy into electricity,
which is used for running the motor pump set. The pumping system draws
water from the open well, bore well, stream, pond, canal etc. The system
requires a shadow-free area for installation of the Solar panel.
Utility
A system with 1800 watt PV array capacity and 2 HP pump can give a water
discharge of 1.4 lakh liters per day from a depth of 6 to 7 meters. This quantity
of water is considered adequate for irrigating about 5-8 acres of land holding
for several crops.
Advantages of a solar water pumping system
● No fuel cost - as it uses available free sun light
● No electricity required
● Long operating life
● Highly reliable and durable
● Easy to operate and maintain
● Eco-friendly
Solar Thermal Tower Power Plants
In solar thermal tower power plants, hundreds or even thousands of large two-axis
tracked mirrors are installed around a tower. These slightly curved mirrors are also
called heliostats; a computer calculates the ideal position for each of these, and a
motor drive moves them into the sun. The system must be very precise in order to
ensure that sunlight is really focused on the top of the tower. It is here that the
absorber is located, and this is heated up to temperatures of 1000 °C or more. Hot air
or molten salt then transports the heat from the absorber to a steam generator;
superheated water steam is produced there, which drives a turbine and electrical

33. generator, as described above for the parabolic trough power plants. Only two types of
solar tower concepts will be described here in greater detail.
Open Volumetric Air Receiver Concept
The first type of solar tower is the open volumetric receiver concept (see Figure 4a). A
blower transports ambient air through the receiver, which is heated up by the reflected
sunlight. The receiver consists of wire mesh or ceramic or metallic materials in a
honeycomb structure, and air is drawn through this and heated up to temperatures
between 650 °C and 850 °C. On the front side, cold, incoming air cools down the
receiver surface. Therefore, the volumetric structure produces the highest
temperatures inside the receiver material, reducing the heat radiation losses on the
receiver surface. Next, the air reaches the heat boiler, where steam is produced. A duct
burner and thermal storage can also guarantee capacity with this type of solar thermal
power plant.
Pressurized Air Receiver Concept
The volumetric pressurized receiver concept (see Figure 4b) offers totally new
opportunities for solar thermal tower plants. A compressor pressurizes air to about 15
bar; a transparent glass dome covers the receiver and separates the absorber from the
environment. Inside the pressurized receiver, the air is heated to temperatures of up to
1100 °C, and the hot air drives a gas turbine. This turbine is connected to the
compressor and a generator that produces electricity. The waste heat of the gas
turbine goes to a heat boiler and in addition to this drives a steam-cycle process. The
combined gas and steam turbine process can reach efficiencies of over 50 %, whereas
the efficiency of a simple steam turbine cycle is only 35 %. Therefore, solar system
efficiencies of over 20 % are possible.

34. 4. Schematic of two types of solar thermal tower power plant, showing (a) an open
volumetric receiver with steam turbine cycle and (b) a pressurized receiver with
combined gas and steam turbine cycle
Comparing Trough and Tower

35. In contrast to the parabolic trough power plants, no commercial tower power plant
exists at present. However, prototype systems – in Almería, Spain, in Barstow,
California, US, and in Rehovot, Israel – have proven the functionality of various tower
power plant concepts.
The minimum size of parabolic trough and solar tower power plants is in the range of
10 MWe. Below this capacity, installation and O&M costs increase and the system
efficiency decreases so much that smaller systems cannot usually operate
economically. In terms of costs, the optimal system size is in the range of 50–200
MWe.