engineers are encouraged to take up new initiative under my mentorship to learn new things and do something good for the world.pl do encourage young engineers from colleges and adopt them for better future.
SOLAR DEVELOPMENT IN INDIA
Niyant Singh, Department of Electronics and Telecommunication, Bharati Vidyapeeth
College of Engineering, Navi Mumbai.
Today, India has the largest decentralized solar energy programme, the second largest biogas
and improved stove programmes, and the fifth largest wind power programme in the world.
Primarily my aim is to explain people about the emerging solar field in India. The main
reason for no quick development is because general public is still unaware about solar
products and the benefits of renewable energy. Photovoltaic’s can provide tiny amounts of
power for watches, large amounts for the electric grid, and everything in between.
Concentrating solar power technologies use reflective materials to concentrate the sun's heat
energy, which ultimately drives a generator to produce electricity. Hence in this report I have
covered every single aspect of solar power from basic solar cell to uses applications, products,
market and future plans. This report gives an overview of the menu of technologies and the
scope for solar development in India. It tells the people in brief about the current position of
solar energy in India, the potential in various areas and the targets that the country has set for
itself, thus preparing the ground for more comprehensive information and a ready reckoner.
We realize the purchase of a photovoltaic system can be a challenging task. Here you can find
information about how solar power is generated, how solar systems are constructed and
How does a PV system work?
ALL YOU WANTED TO KNOW
ABOUT SOLAR CELLS
How is solar energy generated and how
much of it can be tapped?
Solar energy is generated by converting
sunlight into electricity. The potential of
solar power can be estimated from fact
that, on an average, each square meter of
land is exposed to enough sunlight to
produce 1700 kWh (or units) of power
every year. That’s enough to power two
100W bulbs for 24 hours a day, throughout
Figure 1: Working of a PV cell
At the heart of the PV systems are PV cells
that do the conversion. A number of PV
What are the main technologies used to
cells combine together to make a PV
harness solar power?
module or the so called ‘panels’. Normally
Photovoltaic (PV) systems and the bigger the panel, the higher it’s power
concentrating solar power (CSP) plants are generating capacity. The panels collect
the two most important solar technologies. photons- particles of solar energy- from the
In India, the technology most commonly in sun, and convert them into electrical
use domestically is the solar water heating power. The power created then flows into
system. an inverter to convert it into a form (AC
current) that is acceptable to electrical near Seville in Spain produces electricity
with 624 large movable mirrors called
Figure 2 : the basic solar Cell, a Module or Panel
Figure 4: A CSP plant showing mirrors
and an Array of solar cells
concentrating sun’s energy on thermally insulated
steel pipe carrying heated water to turbines
How do CSP Plants work?
How energy efficient is PV technology?
CSP or Solar thermal power plants
generate power like conventional power Efficiency is measured by the proportion
systems. But instead of using fossil fuels, of sunlight that a PV cell can convert to
they use solar energy. Gigantic arrays of electrical energy. The first Solar cell,
mirror reflectors concentrate the suns Created in 1883, had an efficiency of 1%.
radiation to produce steam, which drives a Today, most commercial PV devices have
turbine to generate electricity. efficiencies of 16-20%. Incredibly, the
National Renewable Energy Laboratory
(NREL) in the US recently engineered a
device that converts a stunning 40.8% of
sunlight that hits it into electricity.
Figure 3: solar Power tower surrounded by a field
of heliostats( huge mirrors) which concentrate
sun’s heat at one point
Figure 5: A simple solar PV Panel (first of its kind)
What are the major applications of PV
and CSP systems?
PV systems have been used to power small
What are the different kinds of PV cells?
and medium sized applications, from the
calculator, which is powered by a single There are three generations of Photovoltaic
cell, to off-grid houses, which are powered cells, based on the materials they are made
by an array of cells. Multi-megawatt (MW) of (see pictures).
PV plants are also slowly gaining ground.
CSP is used for large scale generations of The first generation, Crystalline Silicon, is
electricity, It is ideal for Sun-drenched made of one or more small silicon crystals.
regions like Parts of Rajasthan and It accounts for about 90% of cell
Gujarat- for utility scale generation, production today. To make an effective PV
Abengoa’s solar 11 MW solar power tower cell, silicon is quot;dopedquot; to make it n-type
and p-type. The challenge here is to carve
the thinnest of Wafers, as this translates to
smaller quantity of expensive Silicon- and
therefore, lower costs. Wafer thickness has
dropped from 0.32 micrometres in 2003 to
0.17 micrometres in 2008 (1 micrometre =
Figure 7: A Nano solar cell
Silicon is still the most popular solar-cell
material for commercial applications
because it is so readily abundant (it is
actually the second most abundant element
in the Earth's crust-second only to
oxygen!). However, to be useful in solar
cells, it must be refined to 99.9999%
Figure 6: A C-Si (Crystalline silicon) solar panel
Thin films are the second generation. Thin Balance of System
film modules are made by depositing
We may think of a complete PV system as
extremely thin layers of photosensitive
comprising three subsystems. On one side,
materials on to sheets of glass, stainless
we have the PV devices (cells, modules,
steel and even plastics.
arrays, etc.) that convert sunlight into
Today, amorphous silicon is commonly direct-current (dc) electricity. On the other
used for solar-powered consumer devices side, we have the load, or the application
that have low power requirements (e.g., for which the PV electricity is intended.
wrist watches and calculators). Between these, we need a third subsystem
to enable the PV electricity to be properly
Amorphous silicon absorbs solar radiation applied to the load. This third subsystem is
40 times more efficiently than does single- generally referred to as the quot;balance of
crystal silicon, so a film only about 1 systemquot; or BOS
micron (one one-millionth of a meter)
thick can absorb 90% of the usable solar
energy. This is one of the most important
factors affecting its potential for low cost.
These characteristics make amorphous
silicon the leading thin-film PV material.
The third generation comprises nano and
organic PV (OPV) cells. Nano materials
possess higher strength and flexibility and
have displayed the ability to trap more
energy than conventional PV cells. OPV
cells mostly contain organic molecules.
Some scientists believe OPV cells will be a
Figure 8: balance of system
cheaper alternative to traditional inorganic
cells due to the economics of scale derived This simple illustration shows the elements
from large-scale production of organic required to get the power created by the
polymers. PV system to the end load (in this example
a house). The stand-alone system (a) uses
battery storage to provide dependable dc
electricity day and night. Even for a home cheaper than existing grid power. The
connected to the utility grid (b), PV can current challenge in the race to achieve
produce electricity during the day grid parity is to push down manufacturing
(converted to ac through the power cost of PV cells to sub-dollar levels, from
conditioner). This configuration is $2-2.5 (for crystalline silicon) and $1.35
desirable because extra electricity can be (for thin films) today.
sold to the utility during the day, and the
utility can in turn provide electricity at
night or during poor weather.
APPLICATIONS OF SOLAR
The BOS typically consists of structures
for mounting the PV arrays or modules and
Today, solar-generated electricity serves
the power-conditioning equipment that
people living in the most isolated spots on
adjusts and converts the dc electricity to
earth as well as in the centre of our biggest
the proper form and magnitude required by
cities. First used in the space program, PV
an alternating-current (AC) load. If
systems are now both generating electricity
required, the BOS also includes storage
to pump water, light up the night, activate
devices, such as batteries, for storing PV-
switches, charge batteries, supply the
generated electricity to be used during
electric utility grid, and more. Whether you
cloudy days or at night
are a homeowner, farmer, planner,
Do Solar systems produce Electricity all architect, or just someone who pays
electric utility bills, PV may already touch
your life in some way.
They can if they store the Sun’s energy
either in batteries or any other medium. Simple PV systems
Otherwise they will generate electricity
The same sunny days that dry out plants,
only when the sun is shining.
make animals thirsty, and heat up buildings
Do they work when it’s cloudy or cold? and cars are also good days for generating
electricity with photovoltaics. This
Yes, on cloudy days their output reduces, electricity can be used to power water
in proportion to sunlight they receive, pumps for irrigation and drinking wells,
when it’s cold (and sunny), they work well and ventilation fans for air cooling. For
and, in fact, generate more power at lower this reason, the simplest PV systems use
temperatures. This is because, as with most the dc electricity as soon as it is generated
electronic devices, they operate more to run water pumps or fans.
efficiently when it’s cooler.
How long do PV systems last? Are the
PV modules brittle?
A PV system that is designed, installed and
maintained well should run for atleast 20
years. The basic PV module has no moving
parts and can last more than 30 years,
unless struck with heavy force, PV
modules will not break easily. They are
designed to withstand all kinds of
extremes, including arctic cold, desert heat, Figure 9: A woman drawing water from PV
tropical humidity, high- speed winds, even powered pump
hailstones. Even if they break, unless the
PV with battery storage
cells are damaged, the system will continue
to work. Storing electrical energy makes PV
systems a reliable source of electric power
What is Grid parity?
day and night, rain or shine. PV systems
with battery storage are being used all over
It is the point at which the cost of
the world to power lights, sensors,
producing solar energy is equal to or
recording equipment, switches, appliances, Utility-scale Power
telephones, televisions, and even power
Large-scale photovoltaic power plants,
consisting of many PV arrays installed
together, can prove useful to utilities.
Utilities can build PV plants much more
quickly than they can build conventional
power plants because the arrays themselves
are easy to install and connect together
electrically. Unlike conventional power
plants, PV plants can be expanded
incrementally as demand increases.
Figure 10: A Solar Lantern with batteries powered
by PV system.
PV systems with batteries can be designed
to power dc or ac equipment. People who
want to run conventional ac equipment add
a power conditioning device called an
quot;inverterquot; between the batteries and the
Figure 12 : A nuclear to solar converted 2 MW
power plant in California serves 660 homes.
PV connected to utilities
Hybrid Power systems
Where utility power is available, a grid-
connected PV system can supply some of
Hybrid systems combine a number of
the energy needed and use the utility in
electricity production and storage pieces to
place of batteries.
meet the energy demand of a given facility
or community. In addition to PV, engine
generators, wind generators, small hydro
plants, and any other source of electrical
energy can be added as needed to meet
energy demands and fit the local
geographical and temporal characteristics.
These systems are ideal for remote
applications such as communications
stations, military installations, and rural
Figure 11 : A PV battery charging station for
The owner of a grid-connected PV system
can not only buy, but can also sell,
electricity each month. This is because
electricity generated by the PV system can
be used on site or fed through a meter into
the utility grid. When a home or business
requires more electricity than the PV array
is generating (for example, in the evening),
the need is automatically met by power
from the utility grid. Figure 13 : A hybrid (wind and Solar) power
Water Heating and Cooking ADVANTAGES AND DRAW-
BACKS OF SOLAR ENERGY:
Solar energy is a renewable resource.
Although we cannot utilize the power of
the sun at night or on stormy, cloudy days,
etc., we can count on the sun being there
the next day, ready to give us more energy
and light. As long as we have the sun, we
can have solar energy.
Solar cells are totally silent. They can
extract energy from the sun without
Figure 14 : A typical Solar water heating system
making a peep. Now imagine the noise that
Solar hot water systems use sunlight to the giant machines used to drill for and
heat water. Total installed capacity of solar pump oil make!
hot water systems growth is 14% per year.
Solar energy is non-polluting. Of all
China is the world leader in the
advantages of solar energy over that of oil,
deployment of solar hot water systems
this is, perhaps, the most important. The
with 80% of the market. Solar water
burning of oil releases carbon dioxide and
heating is highly efficient (up to 86%) and
other greenhouse gases and carcinogens
is particularly appropriate for low
into the air.
temperature (25-65 °C) applications such
as domestic hot water, heating swimming
Solar cells require very little maintenance
pools and space heating. The basic
(they have no moving parts that will need
components of a solar water heating
to be fixed), and they last a long time.
systems are solar thermal collectors, a
storage tank and a circulation loop. Although solar panels or solar lights, etc.,
may be expensive to buy at the onset, you
Solar cookers and CSP systems use
can save money in the long run. After all,
sunlight for cooking, drying and
you do not have to pay for energy from the
pasteurization. Solar cookers offset fuel
sun. On the other hand, all of us are aware
costs and reduce demand for local
of the rising cost of oil.
firewood. Solar cookers also improve local
air quality by removing a source of smoke. Solar powered lights and other solar
The most common designs are box powered products are also very easy to
cookers, concentrating cookers and panel install. You do not even need to worry
cookers about wires.
Here are the only disadvantages of solar
Solar cells/panels, etc. can be expensive
(until 2010; now things are changing).
Solar power cannot be created at nights
still now methods have been researched to
store solar generated electricity through
Figure 15 : Women in Rajasthan Using CSP system
As you can see the advantages of solar
energy create a much longer list that the
disadvantages and the disadvantages are
things that can be improved as technology stratagems. “The energy challenge is
critical, it cannot wait,” says Shyam Saran,
The Prime minister’s special envoy on
climate change “Solar Power appears to be
most promising when compared with other
SOLAR POWER, THE BIG renewable sources.”
Nearly 76 million Rural Households in
The Cost Factor India do not have access to electricity.
While efforts to take grid power to them
One area that needs a stimulus is the
are on, the general belief is that they are
manufacturing space. India cannot afford
unwilling or unable to pay for modern
to miss the solar bus as it did the
forms of energy, such as solar power. This
electronics one decade ago. The need to
is a myth, and villagers from different
ramp up and bring in economics of scale is
corners of India have proved it to be so.
imperative. In solar the fundamental
Take the case of Gorhori Maity, a poor
challenge is technology and cracking the
farmer who ekes out as living from 1.5
barrier of $ per watt manufacturing cost to
bighas of land; Maity pays Rs. 100 for
enable grid parity. Unlike in other sectors,
three light points drawn from a 110 kW
it’s not merely a volume up, cost down
solar mini-grid in the sundarbans. “It’s
game in solar. The key is to pursue
difficult but I scrape through,” he says.
electron-level strategies, improve
Down south, in Karnataka, Narayanpatti, a
efficiency and cut-off costs.
silk Farmer in Devenhalli village, has been
paying monthly bank instalments of Rs.
In sophistication, accuracy and efficiency
1,200 for a solar home lighting system
we are as good s the west. The question is
[SHS] costing Rs. 23,000. In Bhopu Dhani
“can they do it cheaper than us”.
village, Rajasthan, Hema Ram purchased
an SHS without even seeking government
Oil’s well, but Solar is better
subsidies. “The paperwork is
The shift to solar is inevitable because cumbersome,” he says. The village is
other energy sources have limitations. supposedly on the future grid-extension
Designing and building a nuclear plant can map and official’s invariable fob off
take as long as eight years. Oil on the other villagers seeking solar subsidies. “We have
hand, may seem attractive today, at $ 35 a waited long enough for grid power,” Says
barrel, but it is volatile. It would be foolish Ram.
for India to wait until the next round of
high oil prices to act. Moreover, oil is Grid power is a carrot that successive
finite. OPEC countries, sitting on government have held out as the solution
insufficient oil assets, nearing end-life, will to all power problems, urban or rural.
have to make huge investments in Where it is not technically or economically
production. “It won’t be profitable for feasible to link remote and inaccessible
OPEC to sustain low prices for long. Oil villages, the government has been pushing
will go to $ 80 a barrel and above within renewable. But the fact is, much more can
the year.” predicts shubhranshu Patnaik, be done. Large chunks of the rural
Executive Director, Pricewaterhouse hinterland can be provided power through
Coopers. decentralised distributed generation
systems. Solar power has proved very
Again, coal, which fires the majority of successful wherever it has been tried. Be it
India’s power plants, is expected to suffer through standalone SHSs or mini grids, it
a global supply shortage. By 2011-12, has delivered electricity locally, where it is
importing costly coal will be unviable as needed. However, while its feasibility has
generation cost will go up three times,” been proven form some time now, it lacks
says SP Gon chaudhuri, Managing scale –penetration has been appallingly
Director of WBGEDC. Even among low. Around 800,000lanterns have been
renewable options such as wind, hydro or delivered in Rural India. The west Bengal
biomass-based generation, solar scores, Energy Development agency solar power
and policymakers are factoring this into plants in sunderbnas have aggregate
capacity of 707 kW. It benefits only 3450
households. Another 35000 households
LET THERE BE MORE LIGHT
owns SHS. Even then 20 % of population
is served. Even in Sunny Rajasthan 83
villagers have 10 kW solar power plants.
10 kW power plant serve 50 house hold on Rays of Hope
an average. The one area of worry for the
penetration is the cost of the solar system To stimulate demand for solar power, some
offered to the villagers. Even with 50 % countries have adopted renewable energy
subsidy they are not able to go ahead with programmes employing various financial
the solar power plan incentives. On the supply side, the ongoing
credit crisis is limiting the availability of
JOB CREATOR capital or simply cautioning institutions to
lend less. The shadow of recession is
Solar energy will create a new class of jobs
impending new projects and the political
when they are most needed. On the one
will to fund incentive programmes. At the
hand solar energy will make a long way in
same time, we are seeing the emergence of
addressing India’s mammoth power
more financing schemes.
requirements. On the other, it will generate
employment by creating jobs. Given California has proposed to issue bonds to
Unemployment is rising by the day the finance the installations of solar power
latter will prove to be a boon. The ILO systems, with repayment over an extended
(International Labours Organization) period as a surcharge on property taxes. In
predicts that the number of unemployed Germany renting out the commercial roof
people will rise from 190 million in 2007 space for solar power is providing
to 210 million by end of 2009.due to the adequate returns to investors. The rising
financial meltdown. The so called ‘Bottom demand for PV modules has led to
of the pyramid’ is set to widen as another shortages in raw material. This supply
40 million will join those below poverty crunch pushed process up, which acted as
line. India will feel the impact. n incentive for the silicon industry to bring
additional production into the market.
Situations Vacant: Increase in supply will bring down module
prices. This will in turn bring solar
2010 2015 2030
generation tariffs down to the level of grid
Installation 166,51 486,21 2,770,56
tariffs, leading to more investment flowing
Production 47,306 524,729 into solar generation projects.
Wholesaler 14,192 38,436 157,419
Research 6,150 16,656 68,215
In India, solar power generation, at only
Supply 17,740 48,045 196,773
about 2.5 million units per years, forms a
251,90 117,47 3,717,70
negligible part of the country’s renewable
6 7 5
Table 1: Jobs in Solar sector in future years
energy portfolio. Earlier this month, the
(source: (EPIA) European photovoltaic industry
ministry of New and renewable energy
launched a scheme to provide financial
However there is hope. Solar Power has support for the installation of grid
interactive solar power in the 11th five year
the potential to generate jobs across
hierarchies, quickly. That is why President plan (2007- 2012); the limit is 50 MW for
Barack Obama wants to invest $150 the country and 5 MW for individuals
million on renewable, to meet 30% of plants. The programme is better suited to
Americas energy needs by 2030 and would solar PV plant due to the low generation
create over 5 million jobs. A conservative limit on individual plants. Solar thermal
estimate by the European photovoltaic plants require a larger generation capacity
industry association predicts nearly 4 to be visible and would, therefore, not
million jobs in PV-sector worldwide by benefit much from such scheme.
Commercial funding options for energy and cheaper photovoltaic’s to
standalone solar generation projects, provide affordable energy to all.
especially in developing countries like
Also we should learn ‘What it takes to
India, have not yet taken off. This is
innovate technologies is different from
because the cost of generation hasn’t
what it takes to industrialize them’
reached grid parity.
In conclusion, the question is not whether,
A successful solar venture should be
but when, the goal of a self –sustaining
structured with a narrow, well-defined
solar market in developing country like
target market so that the investment
India will be achieved.
offering can be adequately addressing a
relatively homogenous set of needs.
Economics of scale play a big role in
making solar project sustainable. Without a
sizeable service population, a private solar
company cannot run into collection issues
and maintaining systems. ‘Shadows and Light’ and ‘What,
Where, How…..’ by Naren
A supportive legal environment is critical. Karunakaran in Business Outlook
these includes factors like incentives for magazine -Feb 09.
solar energy or absence of competing
subsidised electricity, long term ‘Island in the sun’ and ‘Power to
government electrification plan and legal the people’ by Naren Karunakaran
basis for enforcing loan collections. in Business Outlook magazine- Feb
Commercial grid tied projects are
becoming increasingly important in ‘Let there be more light’ by
countries where the local solar PV market Soumya Banerjee and Priyanka
is beginning to build scale or in countries Sood in Business Outlook
like India, China and Algeria, where magazine-Feb 09.
incentives or subsidy programs have been
announced. This would help long term www.suryaprakash.com/tech.htm
investors in preparing the ground for
anticipated future growth. •
Even though energy from renewable
energy sources is growing rapidly, the
overall share is only expected to increase
marginally over the coming decades as the
demand for energy also grows rapidly,
particularly in many developing countries.
In India, the scientific focus is deliberately
moving towards transforming coal into
clean energy as well as harnessing
hydropower. The recent surge in nuclear
energy is also diverting focus from the
solar energy enhancement. In all
probability, the Indian government will
support off-grid solar energy production
through a decentralized manner. In spite of
this, India needs to focus research on solar