|
| |
 |
Solar
Energy |
 |
|
We've used the Sun for drying clothes and food for
thousands of years, but only recently have we been
able to use it for generating power.
The Sun is 150 million kilometres away, and
amazingly powerful.
Just the tiny fraction of the Sun's energy that
hits the Earth (around a hundredth of a millionth
of a percent) is enough to meet all our power
needs many times over.
In fact, every minute, enough energy arrives at
the Earth to meet our demands for a whole year -
if only we could harness it properly.
|
|
How it works
There are three main ways that we
use the Sun's energy:-
Solar
water heating , where heat from the Sun
is used to heat water in glass panels on your
roof.This means you don't need to use so much gas
or electricity to heat your water at home.
Water is pumped through pipes in the panel. The
pipes are painted black, so they get hot when the
Sun shines on them. This helps out your central
heating system, and cuts your fuel bills.
Solar heating is worthwhile in places, where you
get lots of sunshine.
|
 |
|
Solar
Furnaces, use a huge array of mirrors
to concentrate the Sun's energy into a small space
and produce very high temperatures.
Solar
Cells (really called
"photovoltaic" or
"photoelectric" cells) that convert
light directly into electricity. In a sunny climate, you can get enough power to
run a 100W light bulb from just one square metre
of solar panel. This was originally developed in order to provide
electricity for satellites, but these days many of
us own calculators powered by solar cells.
|
 |
Solar cells provide the energy to run satellites
that oribt the Earth. These give us satellite
TV, telephones, navigation, weather forecasting,
the internet and all manner of other facilities.
Advantages
- Solar energy is free - it needs no fuel and
produces no waste or pollution.
|
- In sunny countries, solar power can be used
where there is no easy way to get electricity
to a remote place.
- Handy for low-power uses such as solar
powered garden lights and battery chargers
Disadvantages
- Doesn't work at night.
- Very expensive to build solar power
stations. Solar cells cost a great deal
compared to the amount of electricity they'll
produce in their lifetime.
- Can be unreliable unless you're in a very
sunny climate. In the United Kingdom, solar
power isn't much use except for low-power
applications, as you need a very large area of
solar panels to get a decent amount of power.
|
|
Highlights
There are about 300 clear sunny days in a year in
most parts of India. This is equal to over 5,000
trillion kWh/year, which is far more than the
total energy consumption of the country in a year.
- The daily average solar energy incident over
India varies from 4-7 kWh/m2, depending upon
location
- SPV systems have found applications in
households, agriculture, telecommunications,
defence, and railways among others. In the
last two decades, the cost of PV has gone down
significantly, increasing affordability for
dispersed rural applications
- Costs are expected to reduce further thus
creating more demand
- About 66 MW aggregate capacity (about
10,80,000 individual PV systems and power
plants) have been installed for various
applications. In addition, PV products of 55
MW aggregate capacity have been exported
- Under MNES's PV programme, around 8.20 lakh
systems have been installed - aggregating to
about 29 MW. This includes 5,09,894 solar
lanterns, 2,56,673 home lighting systems,
47,969 street lighting systems, and 5,000
water pumping systems. About 3.97 MWp of
aggregate capacity of stand-alone and
grid-interactive PV power plants have been
installed as on March 31, 2003. These include
State's own programmes also.
- MNES is implementing two major schemes for
the deployment of stand-alone PV systems in
the country:
- Lighting systems, stand-alone power plants
and other specialised systems, implemented
mainly through SNAs/departments/corporations,
'Aditya' solar shops operated by
Manufacturers' Associations and NGOs
- Water-pumping systems for agriculture and
related uses, implemented through IREDA and
SNAs
- West Bengal, Rajasthan, Uttaranchal,
Chattisgarh, Ladakh, Lakshadweep Islands,
Andaman and Nicobar Islands and the
North-eastern states are prominent regions
where SPV solar home systems and power plants
are in demand
- About 3600 remote villages and hamlets have
been electrified with SPV systems and power
plants. Out of these 915 remote villages have
been electrified during 2001-02 and 2002-03
Aims and Targets
An all India SPV programme to
develop cost-effective PV technology and its
applications for large-scale diffusion in
different sectors, especially in rural and remote
areas is under implementation by MNES. Major
components of PV programme include:
- R&D
- Demonstration and utilisation
- Testing and standardisation
- Industrial and promotional activities
Courtesy: MNCS(Ministry
of Non-conventional Energy Sources) http://mnes.nic.in
|
|
|
|
| |
 |
|
 |
|
