Economic growth, energy demand and environmental pressures are positively correlated.  So has been the case in India these past years.  The challenge for us is to break this nexus. It is to find solutions that will support increasing affluence without causing ecological damage.  It is to develop energy systems that will halt greenhouse gas emissions and that will over time, stabilize atmospheric carbon levels to below the generally accepted safe maximum of 550 mppv.  This is not a challenge unique to India.  It confronts most countries.  But it is of unique severity given the size of our population, the pressures of urbanization and the growth in demand for fossil fuels as people move up the energy ladder.

As the world’s second most populous country, India is home to a broad spectrum of opportunities and challenges brought on by energy and environmental sector changes, evolving environmental standards, rapidly changing energy policy and regulation, increasing industrialization and economic globalization.  Its rapidly growing population has resulted in expanding energy capacity needs and associated transmission and environmental difficulties.  A reform and restructuring programme launched in 1991 has led to substantial improvements in the way the energy sector is regulated in India.  India is potentially the largest single market for renewable energy in the world.  Over 17% of the people on earth live in India and approximately 60% of the Indian population lacks electricity.  India has plentiful solar energy.

The energy produced by the sun each day is a vast and largely untapped resource.  Solar energy can be used to heat domestic hot water, offset a building’s space heating needs, or to produce electricity.  In contrast to our current energy system, which relies on burning fossil fuels like coal and oil, solar energy is pollution-free and virtually unlimited in supply.

How the sun produces energy:

The sun is a sphere of high temperature gases about 1.4 million kilometers in diameter (about 8,70,000 miles).  The temperature of the interior of the sun is 15 million degrees Kelvin (about 27 million degrees F).  This high temperature combined with a pressure that is 70 billion times higher than atmospheric pressure on earth creates ideal conditions for fusion reactions.  Fusion reactions come about by the union of light atomic nuclei to form heavier nuclei, releasing a large amount of energy in the process.

The amount of solar energy impacting the surface of earth is 1000 watts per square metre, which is about 32.8 million MW every second on the Indian land mass.  A large part of this heat and light energy is absorbed by plants, animals, the atmosphere and the earth’s surface.  It is this heat energy that is making the planet habitable.  A large part of the incident heat is reflected to the outer space or radiated back to space.  A small part of this energy (an infinitesimally small part) is attempted by man to be trapped and used as heat or photovoltaic electric current.  The sun’s light and heat energy may be captured and used in the form of:

• Heat in “solar thermal” applications
• Or it may be converted directly into electricity to power electrical devices using photovoltaic cells.

How does a Solar Electric System work?

The word Photovoltaic comes from two roots meaning “light” (photo) and “voltage producing” (voltaic).  When the sun’s rays fall on a PV cell it increases the energy stored in the atoms of that wafer.  That increased energy leaves the electrons free to move about and electricity will flow when conducting wires are attached to the cells.  A number of cells are wired together into a sealed module and modules can be connected together into larger arrays.  PV produces electricity in a process that is completely self-contained, has no moving parts and where no materials are consumed or released.

Solar arrays are usually mounted on rooftops or on a ground mounted structure.  When arrays are connected to other components of a PV system, the system can provide electricity for a variety of uses.  Electricity from PV systems can be fed directly on to electric lines for use by other electric customers.

The electricity produced by PV panels is DC (direct current).  This is different from the AC (alternating current) that comes in from the utility lines through the wall sockets in your house.  Therefore, systems connected to the utility grid have an inverter that converts power from DC to AC, making it compatible with the electricity flowing through the power lines.

Enough sunlight falls on the earth’s surface each day to meet the world’s energy demand.  Harnessing this abundant energy source can provide many benefits for residents, businesses and facilities.

It is estimated that India needs to double its generation capacity, adding 10,000 MW in the next ten years, which will require more than US$ 140 billion in new investment to meet its growing capacity needs. In recent years, promising technological advances and an expanding array of potential applications for photovoltaic (PV) systems have bolstered the prospects for a thriving solar energy industry.  However, progress has been hindered by on going financial barriers, regulatory hurdles and the high cost of solar power.