Transcript max`s group - slider-chemistry-12

Liquid Junction
Photovoltaic Device
Investigation
As compared to a dry cell
What is it?
• These solar cells have the ability to convert light
energy from the sun into electrical energy
• These solar cells are almost twice as efficient at
converting light energy into electrical energy as
those currently commercially available
• Applications: provides power for homes and
outback installations, lighthouses, pumping water
and emergency telephones
Chemistry
Liquid Junction Photovoltaic Device
Dry Cell
Cost and Practicality
Liquid Junction Photovoltaic Device
Dry Cell
• As a result in the different application
of the cell, it is more expensive than a
dry cell
• In comparison to other photovoltaic
devices, it is cheaper and easier to
produce
Advantages
• More efficient and environmentally
friendly way of obtaining electrical
energy
• Durable
• The metal oxide that is used (titanium
oxide) is easily obtainable
• Relatively cheap
Advantages
• Readily available for purchase and use
• Useful when small currents are needed
(e.g. for a torch or toy helicopter)
• Easy to store
• Simple to use
Disadvantages
• Can be prone to leaking
• Small current may be insufficient
Impact on Society
Liquid Junction Photovoltaic Device
Dry Cell
Society has been trying to harness the ability of
converting sunlight into energy since the 1960s, this is
because the reliance on fossil fuels is ineffective in an
environmental and social sense. Therefore
Photovoltaic cells present benefits for society. These
societal benefits are that it gives a possible solution to
finding a renewable energy source that can be
commercialised on a large scale that fossil fuels and
dry cell batteries have. If photovoltaic cells can be
commercialised then it offers a solution to society to
enable them to lower the necessity of fossil fuels and
convert to renewable sources of fuel. However this
would also have a detrimental effect on society, as the
energy industry is very large meaning that those who
do not have the capabilities or who have not been
making steps into renewable energy will fall behind
and fail as businesses, meaning that unemployment
could increase in society.
Dry cell batteries have a large impact on society,
without us realising their importance. Dry cell
batteries are used in many household appliances
which we could not use without, such as a torch;
portable light would not be readily available if dry cell
batteries did not exist. The dependence on dry cell
batteries comes from their portability, small size and
they are very cheap and easy to create. However as
these dry cell batteries have short shelf lives, meaning
they do not last long, has a negative effect on society
as it creates a lot of un-recyclable toxic waste as the
zinc casing of the batteries react with the ammonium
ions in the battery causing it to deteriorate and leak
toxic substances which are harmful for animal life, this
will be covered in depth in the environmental stage.
Environmental Impact
Liquid Junction Photovoltaic Device
Dry Cell
- The environmental impact of the Gratzel Cell is
low, in fact beneficial as it uses a renewable source
of energy and titanium dioxide is a mineral found
in sand. Over 95% of all the solar cells produced
worldwide are composed of the semiconductor
material Silicon. As the second most abundant
element in earth`s crust, silicon has the advantage,
of being available in sufficient quantities, and
additionally processing the material does not
burden the environment. Though, the photovoltaic
cells do not use silicon often, instead they use
iodide, ruthenium coated with titanium oxide.
- Ruthenium is one of the rarest metals on Earth.
Ruthenium compounds are encountered relatively
rarely by most people. All ruthenium compounds
should be regarded as highly toxic and as
carcinogenic. Iodide and titanium dioxide has no
reported effects on the environment.
- Dry cell batteries are household batteries used in
power tools, watches, video cameras, calculators,
hand-held vacuum cleaners, flashlights, toys,
hearing aids, etc. They include alkaline, alkaline
rechargeable, lead acid sealed, lithium, metal
hydrate, mercuric oxide, nickel-cadmium, silver
oxide, and zinc-air batteries. The environmental
impact of mercury, silver, lithium, cadmium, lead
and acid all have the potential to be hazardous
waste. If the batteries are burned or land filled,
the heavy metals in them can be released into the
environment. These metals could pollute
groundwater, surface water and the air when
burned. Not to mention the risks to the people
who work around these landfills.