Solar Energy - What is it and what does it promise?

Using the sun to benefit society is nothing new and is something we have been doing for thousands of years, whether it’s starting fires, drying meat, or powering your house we are continually finding increasingly complex ways to utilise this limitless resource.

How Does Solar Energy Work

Solar energy is basically the harnessing of the suns energy and light into the production of electricity. This electricity is generated by the use of photovoltaic cells (Solar Cells.) These clever devices capture energy from the sun by the photovoltaic effect. The cell itself is really quite a simple device and a good way to think of it is as a sandwich. There are two silicon layers, the lower is called the positive type Silicon (P-type) which contains a lesser amount of negatively charged electrons than the upper layer which is called the negative type silicon (n-type.)

Now, sunlight is made up of tiny particles called photons and as these photons enter the silicon sandwich they pass their energy onto the electrons which causes them to move. It’s this movement that leads to the creation of electricity as the P-type electrons on the lower layer jump up to the n-type layer. Now the n-type layer already contains many electrons, so the extra ones that have recently moved are pushed onto the circuit which in turn creates electricity.
The problem here is that photovoltaic cells are very costly and the silicon manufacturing process is very complex and although the market is growing at around 35% annually there still hasn’t been a significant reductions in the production costs.

Solar Energy has often been lauded as the saviour of mankind and the solution to all of our energy problems, and although it does have incredible potential this is certainly not the case now.
Before it can live up to the hype a significant amount of research is needed to reduce the cost/efficiency ratio, as economically it’s not a very efficient way of generating electricity.
Still, the day when Solar Energy really starts to contribute to our global energy supplies may not be that far off, as to date there has been a great deal of research in this area and increased funding and grants from Governments keen to be seen doing the right thing. Which is leading to more research into the area and allowing producers to experiment with more efficient manufacturing techniques.

An interesting fact to know is that in one hour the earth is hit with more solar energy than our total fossil fuel energy consumption over one year.

Pros and Cons of Solar Energy:

Solar Energy Pros

• It’s free, and in there is an infinite supply.
• It produces no pollution (air /environmental / noise) and doesn’t emit any toxins.
• There are no Geopolitical issues as it’s available everywhere on the globe. This also has a production benefit as with its easy availability electricity can be generated anywhere, unlike fossil fuels which are quite often located in politically unstable or inhospitable regions.
• Research is increasing in this area so the efficiency of the photovoltaic cells is seeing rapid improvement. Also systems are becoming smaller and less noticeable.
• Governments are offering financial incentives and tax breaks to people who install solar systems.
• Remote locations that can’t be connected to a local grid have the ability to generate their own electricity.
• Solar systems are low maintenance and require very little upkeep and monitoring.

Solar energy Cons

• Solar cells are expensive, both for home and Industrial use – the cost of setting up a decent sized solar farm is astronomical.
• It’s not as clean as some may have you believe. Waste products are created during the manufacturing process.
• Solar energy can only be generated during daylight hours.
• Weather and pollution can effect the efficiency of solar cells, so it’s neither predictable or that efficient.

Whether Solar Energy will eventually live up to it’s promise is still to be seen, but with our dwindling reserves of fossil fuels, this does seem like one of the most logical alternatives we should be turning to.