2. Aim
This summer I learnt more about solar power and how it could be implemented in India,
especially in the villages here as most of them have no electricity. I approached Maxwell
Solar and Wind Energy who are implementing this technology all over India. While
working with them I learnt about the various types of solar energy solutions available
today and how each of these can be used in different places. I also took part in helping
them set up a small solar power plant in a village near Mumbai, Talavli which was to
provide solar energy for the school there. Talavli received power from the grid itself,
however this was fraught with interruptions and was available for only 8 hours a day.
Hence a small solar plant was installed to provide electricity for the school. The benefits
and economic impact of this activity was studied.
3. What is Solar Power?
The sunsâ energy can be converted into electricity, either directly using
photovoltaics (PV), or indirectly using concentrated solar power (CSP).
Concentrated solar power systems use lenses or mirrors and tracking systems to
focus a large area of sunlight into a small beam. Photovoltaics convert light
energy into an electric current using the photovoltaic effect.
4. Types of Solar Power Technologies
Solar Thermal
⢠Solar Hot Water: Heating water with solar
energy
⢠Large scale thermal power generation plants
Solar Photovoltaic (PV)
⢠Photovoltaic Systems: Producing electricity
directly from sunlight using solar cells.
⢠Solar Process Space Heating and Cooling:
Industrial and commercial uses of the sun's
heat.
5. Photovoltaic Systems
⢠Photovoltaics is the direct conversion of light energy into electric energy at
the atomic level. Some materials exhibit a property known as the
photoelectric effect that causes them to absorb photons of light and release
photoelectrons. When these electrons are captured by a target, an electric
current results that can be used as electricity.
⢠Semiconducting materials are used to convert solar energy to direct current
electricity (d.c.) through solar cells.
⢠Photovoltaic systems are the most popular means of obtaining solar power.
6. Types of Solar Panels
⢠Solar panels are used in the PV method of
obtaining Solar Power.
⢠Solar cells are put together to make modules.
These modules are then put together to then
form what are known as solar panels.
⢠These solar cells are made of the
semiconducting material and depending on the
panels each module can contain up to 60 solar
cells. Nowadays modules are being built with
72 solar cells as well.
7. ⢠There are 3 different types of solar panels being
used today which differ mainly in the materials
used for their construction, their costs and their
efficiency.
⢠Most solar modules are currently produced
from crystalline silicon (c-Si) solar cells made of
polycrystalline and monocrystalline silicon.
Crystalline silicon accounts for more than 90
percent of worldwide PV production, while the
rest of the overall market is made up of thin-
film technologies which use cadmium telluride,
CIGS and amorphous silicon. The third
technology is HIT which is becoming
increasingly popular due to its high efficiency.
8. ⢠Comparison of Solar Cells being used today :
Monocrystalline Silicon Polycrystalline Silicon Thin Film Solar Cells
Most efficient panels with an
efficiency of 20 â 23%
Less efficient that
monocrystalline panels with an
efficiency of 17%
These are the least efficient
solar panels today with an
efficiency of 12%
Manufactured from single
silicon crystal.
Manufactured by fusing many
crystals of silicon together.
Manufactured by depositing
thin layers of silicon onto a
substrate base.
Most expensive to produce and
process of manufacture leads
to some waste of silicon.
Cost less to produce than
monocrystalline silicon and
manufacturing process is easier.
Mass production of these cells
is the easiest and hence they are
the cheapest to produce.
Have the longest life of about
40 - 50 years. Degrade slowly.
Degrade slowly. They usually
last for 30 â 40 years.
Degrade the fastest. They have
life expectancy of 25 years.
Performs best at standard
temperatures.
Performs best at moderately
high temperatures.
Performs best at high
temperatures.
10. Inverters
⢠A solar inverter or PV inverter converts the variable direct current
(DC) output of a photovoltaic solar panel into alternating current
(AC) that can be fed into a commercial electrical grid or used by a
local, off-grid electrical network. It is a critical component in a
photovoltaic system.
⢠Most solar inverters are 95% efficient so the loss of energy during
conversion for d.c. to a.c. is small.
⢠All solar energy is produced in d.c. and hence an inverter must be
used to convert it so that the electricity may be used to power the
required appliances.
11. ⢠There are 3 types of solar inverters each of which is used in different circumstances :
Stand Alone Solar Inverter Grid Tie Inverters Battery Backup Inverters
These inverters need not be
connected to the solar panel. They
are in fact charged by d.c. batteries
which are in turn connected to the
solar panels. They are isolated from
the utility grid and hence do not
require anti-islanding protection.*
These inverters convert d.c. to a.c in
such a way to match the phase of a
utility supplied sine wave. These
inverters are designed to shut down
automatically when there is a loss of
power supply. Gird tied inverters are
installed with anti-islanding
protection.*
These are special which have been
developed to get electrical energy
from a battery, manage this battery
energy via an on-board charger and
export all excess energy to a utility
grid. They all have anti-islanding
protection.*
* islanding is a condition where the generator continues to supply power even when it is disconnected from the grid.
12. Tracking Mounts
Tracking mounts are used to sense the amount of sunlight and mechanically move the
solar panels over the course of a day so that they directly face the sun at all times thus
maximising output. Dual axis trackers can change both azimuth and elevation, while
single axis trackers only match the azimuth.
13. Power Meters
Power meters are digital devices that record the amount of energy you use in your
home. The meter is used to calculate your energy use and your monthly electric bill.
These meters are also used to measure the amount of solar energy produced by the
solar panels. Any extra energy produced can be added to the grid which is also
measured by these meters. Consumers receive credit for this extra energy produced.
14. Solar Systems
There are three main types of solar systems in use in India :
⢠On Grid Systems
⢠Off Grid Systems
⢠Hybrid Solar Systems
15. On Grid Systems
⢠On Grid solar systems generate electricity for households or businesses and route
any excess power into the electric utility grid for compensation from the utility
company.
⢠An on-grid connection will allow you to save money with solar panels through
better efficiency rates, net metering, and lower equipment and installation costs.
⢠They are cheaper and easier to install consisting of two main components, an
inverter and a power meter.
⢠Since these systems are connected to the gird their main advantage lies in the fact
that they can be used even when there is no sunlight simply by drawing energy from
the grid itself.
16. ⢠The on-grid system is the cheapest system to implement anywhere.
⢠You only end up paying for the net amount of power you have consumed. All extra power
wouldâve been sold to the grid reducing electricity bills.
17. Off Grid Systems
⢠An off-grid solar system uses batteries for energy storage generated by the solar
panels and is best suited to situations where electric power is needed during
blackouts or premises not connected to the main electricity grid.
⢠They are much cheaper to construct as they donât require power lines to be
extended to remote areas. But other components like generators make this system
more expensive than an on-grid system.
⢠They are the most popular choice of solar system to install in villages. Living off-
grid makes people self sufficient.
⢠These systems require a lot of maintenance especially where the batteries are
concerned as they have to get replaced at regular intervals of time.
18.
19. Hybrid Solar Systems
⢠A hybrid solar system combines the best of
an on-grid and an off-grid system. This
means that even during a power blackout, you
would still have electricity.
⢠Hybrid systems are quite sophisticated and
provide uninterruptable power throughout
the day. Energy is obtained from the sun as
per the graph. Hence even at night when
thereâs no sunlight power may be drawn from
batteries.
20. ⢠These systems also cost a lot less than off-grid solar systems.
⢠These systems cannot be implemented in rural areas if there is no connection to the
electrical grid present.
22. ⢠A small solar power plant was to be set up for the school in a village called Talavli
situated near Mumbai.
⢠The first step taken in this initiative was to survey the land and establish an optimum
size and design for the plant being built.
⢠A detailed report is then prepared by the techno-commercial team. This report is then
approved and work then begins.
⢠The design is taken and all parts of the project are produced / procured at the best
prices available. The best materials are used.
⢠After everything has been organised a team is sent to the site to set up the solar plant.
The real field work now begins.
23. The land was then surveyed and measurements
were taken. The soil was also tested so that the
appropriate cement mixture could be made to
install the mounts for the panels.
Once the plan was confirmed, the villagers were met
with and the land chosen for the project was marked
out.
24. Holes are then dug into the ground so that the mounts may be fitted. Metal plates are placed into
the hole to form a base for the mounts which are then fitted over the plates. The cement mixture
produced on the basis of the soil composition is taken and poured into the holes. The cement is left
to dry thus making a strong structure to hold the solar panels.
25. A row of mounts are installed in this way, and then the structures
for the solar panels are fixed onto the mounts.
26. The mounts and the structures are then checked by the engineer on site. After his
go ahead the solar panels were installed onto the structures.
27. Wires are drawn to all the solar panels and
all of them are connected. The inverter is
then installed in the field. It is covered to
protect it from the elements. All the solar
panels are connected to the inverter. Wires
are then drawn to the batteries and the
meter in a separate specially constructed
room.
28. The school has a battery supply to store excess solar
energy which may be used if solar energy is not
available (at night). It can also be used to supply
electricity if there is a problem with the panels.
Solar panel wiring is connected to the main box.
Connections are made for the school electric supply.
30. Assumptions and Returns on the Plant Built
⢠The plant built was a 6 kWp plant. And the cost of the plant was âš9 lakh. The
plant is expected to run for the next 25 years.
⢠There were no subsides on the plant and the whole cost of the plant was borne by
the company itself.
⢠Since the plant built was a hybrid plant, we have taken into consideration the cost
of gasoline to run the generator in case there is no solar power. For the next 5
years the average cost of generating one unit of electricity is âš11. This is expected
to rise at 2% every year.
31. ⢠At this rate of increase at the 6th year the average cost of electricity would become
âš12.14.
⢠The plant is expected to degrade at 0.10% every year as well. Due to this the
production of electricity will also marginally drop and the price per unit of electricity
would increase.
⢠The plant would produce 9600 units of electricity every year.
⢠The cost of the operation and maintenance of the plant is considered at 1.50% of the
plant cost i.e.. âš13500 per annum as it involves only simple cleaning of the panels.
⢠All equipment is covered under manufacturers warranty for the first 5 years which is
extendable for the balance years upon signing up of an AMC with them.
⢠With the above, the project has an Internal Rate of Return (IRR) of 10.86% and a
payback of 9 years.
32.
33.
34. The implementation of solar power for the school will provide electricity to the
school, thus aiding the education of the children who will form the future of our
country.
In addition to giving an impetus to learning it will also provide employment for
the people in the village itself. People have been employed to maintain the solar
panels and ensure its smooth working throughout the year.
Electricity will also be available throughout the year as the plant installed was a
hybrid plant. This will make sure that there is no stoppage in the childrenâs
education.
The villagers who otherwise relied on the erratic supply of electricity from the
grid, used to burn cow dung to generate electricity which was harmful to their
lives, now have a clean source of energy for their school. This keeps their health
in check as well.
35. Solar Power in India â Economic Impact
India is a tropical country and receives a lot of solar radiation for around 300 days a
year which is the same as 5000 trillion kW of solar power. If the country is able to
harness and make use of this energy then a lot of problems that the country faces
due to its acute energy scarcity will get taken care of. At present the country relies
heavily on fossil fuel based energy sources which are contributing a lot towards the
greenhouse effect and pollution. India has begun to notice the importance of solar
power as a cleaner, greener and more efficient source of energy over the last few
years and its implementation on a country wide scale will be really beneficial.
36. Solar power is appealing because it is abundantly available and offers a solution to
fossil fuel emissions and global climate change. The main problem with solar energy
is that its initial cost is too high. Despite the fact that it does repay its value back over
the years as we have seen in the school village, there arenât many people or
organisations who are willing to fund these projects. The cost of solar power is
slowly reducing though.
Another issue with solar power is that not many people are aware of it in India. As it
is a relatively new technology people are apprehensive about making use of it.
Awareness campaigns would help tremendously to inform citizens about the benefits
of solar.
Many solar plants, however, have been implemented in the country so far such as the
Neemuch Solar Power Plant in Madhya Pradesh, the GEDCOL Solar Power Plant in
Odisha and the Bitta Solar Power Plant in Gujarat. Gujarat has become the leader in
providing solar electricity in India due to the presence of the Thar desert.
37. Lack of proper infrastructure in the electricity industry is one of the main hurdles
in the development of solar power in India. Indiaâs electrical grid system is still
under going development, with majority of the countryâs population especially rural
India still surviving off-grid.
Research and development in cheap solar technology is essential to building up the
solar industry in the country. Infrastructure must be organised and built comprising
of networks of local-grid clusters which would generate electricity for the villages in
that area. This would prevent the government form having to spend a lot of money
otherwise on installing expensive, long centralised power delivery systems. Normal
grid supply systems via power lines is also not possible in the mountainous regions
of the country and hence solar power would be the best alternative to bringing light
to these peoples homes.
38. The creation of jobs is another important aspect of the solar power industry in
India. This will boost Indiaâs economic growth and reduce unemployment levels.
People must undertake the designing, construction, grid connection, and
maintenance of the plant. Skilled and unskilled workers are employed and it has
been seen that smaller projects tend to provide the largest number of jobs (in
accordance with a survey conducted by the NRDC â CEEW)
39. Solar power also impacts trading. Most of Indiaâs solar panels are sourced form
other countries like the USA and Europe. It is important for the government to
bring down trade barriers and reduce the taxes imposed on imports and exports.
This would only bring in further investment into the country and boost Indiaâs
GDP.
Indiaâs solar potential is real and there is a lot of support growing for the industry
as a whole. In the next couple of decades it could become a huge billion dollar
industry. All it requires is proper planning, financing and execution.
Solar Power is the future.
