Stuart Irvine,
director, Centre for Solar Energy Research, North Wales, tells Narayani
Ganesh that efficient and affordable third generation solar technology
could help reduce our dependence on polluting fuels:
What is third generation solar
technology?
The I-Gen cells were of crystalline silicon, fairly high-cost,
manufactured in relatively small volumes. The II-Gen cells had higher
efficiency, whether made of thin wafers or silicon. The III-Gen has
more complex, integrated devices that can reduce reflection and capture
more of the solar spectrum by using one or a combination of optical
methods. They have a wide range.
What is the cost component of solar
energy?
Cost components are photovoltaic (PV) modules, power electronics and
installation. One-half of the total cost you pay would be the module
cost. The rest is spread over the balance of the system including
cabling and connectivity. As with any renewable energy option, solar
power is not the cheapest of options; as production increases, however,
the costs tend to decrease. The biggest adopter of PV solar energy is
Germany. They have an established feed-in tariff system for a number of
years now and it costs less because of economies of scale. India's
ministry of renewable energy is introducing a similar scheme to provide
electricity grid connection to solar energy suppliers. You need to have
a mix of renewable energy resources so that you don't depend on any one
source of electricity.
Are large land areas required to
install PV modules?
It depends on the location. In Europe, PV modules are fixed on
south-facing roofs. The UK Centre for Solar Energy Research has a
facade of 1,000 square metres. Germany has installed solar panels on
roofs of industrial buildings measuring up to 10,000 sq metre each.
China and India are now becoming manufacturing centres. A company in
Kolkata, for instance, is working on an innovative technique to make PV
modules with thin film made with cheaper, compound material to increase
conversion efficiency. A UK-based company is to soon market a new type
of portable plastic solar cell as low-cost mobile phone charger.
How can solar energy be stored?
There are two kinds of storage as far as solar energy is concerned:
on-grid and off-grid. In the UK, it's largely the on-grid that's
important. The DC electricity produced by PV modules are converted to
AC in the grid. There's two-way energy traffic. The building will
supply electricity to the grid during the day and buy from it in the
night. This is called feed-in tariff system. In India, there are
different variations of the scheme. If you have large tracts of
unproductive land that gets sunlight, it's attractive from a seller's
viewpoint because you can feed energy to the grid and get paid for that
without having to buy back.
Off-grid needs battery storage. This is important in India where you
have the rural electrification scheme; solar energy can light up
India's villages. Solar energy would charge batteries that are then
used to power lighting, television sets and refrigerators. Solar
energy-charged batteries would be for high-efficiency lighting purposes
and for other low-power domestic requirements.
http://timesofindia.indiatimes.com/articleshow/4009426.cms
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© 2009 Bennett Coleman & Co. Ltd.
