Harnessing The Power Of Light Topic For - International Year Of Light 2015

2. Why Light Matters?

3. Harnessing A Never Ending Resource – “Light”
- Possibilities
Capturing the sunlight more effectively and economically
by making better photovoltaic cells: The modern solar cells which
are being used for converting solar energy into electricity are powering nearly 26%
Of world where as if we could make better solar cells sun will be powering half of
The world.
Harnessing The Power Of Lightening : Each year about 500 million lightening bolts
Occurs in our atmosphere . This idea was initially proposed by Benjamin
Franklin. You would be surprised to know that each bolt of lightning contains about
5 billion joules ,which is quite large!
If we could harness this great power we could run 56 houses for 24 hours from just a
Single lightening bolt.

4. 1. Most of the powerin lightning is dissipated as thunderand light, which cannot be easily harnessed to
generate electric power.
2. However, even just the electrical current of lightning is considerable — 20,000 amps on average, the
same as 100 steel welders. But the poweris on foronly a brief fraction of a second.
3. The huge surge of electrical current oververy brief times makes storing the energy impractical.
4. Lightning strikes to specific locations are infrequent and inconsistent. This makes scheduling power
availability impractical.
5. Lightning can be very damaging. The collection systems have to be incredibly robust, which would
drive up costs. Lightning is also very dangerous, making it tough on the collection systemworkers.
1. Solarenergy can only be harnessed when it is daytime and sunny.
2. Solarcollectors, panels and cells are relatively expensive to manufacture although prices are falling
rapidly.
3. Solarpowerstations can be built but they do not match the poweroutput of similarsized conventional
powerstations. They are also very expensive.
4. In countries such as the UK, the unreliable climate means that solarenergy is also unreliable as a
source of energy. Cloudy skies reduce its effectiveness.
5. Large areas of land are required to capture the suns energy. Collectors are usually arranged together
especially when electricity is to be produced and used in the same location.
Challenges :