Solar Panel Proliferation

Solar panels are the most common method used to catch the energy available from sunlight and turn it into a form that humans can use – in this case, electricity.  Solar panels can be found all over the place – on mobile homes and yachts, on traffic control units (e.g. warning signs or speed cameras) in remote areas away from the main grid, satellites and space stations(which certainly aren’t going to rely on exhaustible batteries or main grid electricity!), and even more places.  Some recent developments are a sure sign that solar panels are now no longer the preserve of oddballs – and the occasional desktop calculator.

Recent Developments in Solar

These recent developments include the fitting out of the Staples Center (a sports stadium) in Los Angeles with an array of solar panels in its roof to provide the electricity needs of the stadium and make it blackout-proof even if the rest of the city’s power stations go into overload and/or can’t get enough fuel.  The company that won the contract to do this, Solar Power Inc, has further plans to install another array of solar panels in the Nokia Theater.

And more quirky new developments in the world of solar panels are found in vehicles.  This is the latest dream – to come up with a car that performs well but doesn’t need topping up with fuel – all you need to do is to park it out in the sun so you can recharge its solar panels. As in other areas of the automotive world, racing and rich prizes are the way to spur on new developments.  Australia is the proud home of the World Solar Challenge, a car race from Darwin to Adelaide, using solar power only.  This race takes place every two years, and the next one is scheduled for 2009.

How Do Solar Panels Work?

But back to basics.  How do solar panels work?  The glib, quick answer is to say that solar panels use the photovoltaic effect to generate electricity.  Photovoltaics and the photovoltaic effect is a practical application of quantum physics (don’t panic if you’re not scientifically minded – you can use solar panels even if you don’t understand the science behind them).

The photovoltaic effect of solar panels works like this:

• Electromagnetic energy in the form of sunlight/photons hits the right sort of surface (metallic or semiconductors like silicone, which is the substance used most often in solar panels).
• The photon is absorbed, and this gives an electron enough energy to make the famous quantum leap.
• The free electron can get a current going if it is not reabsorbed (if it does, the energy is discharged in another form, such as heat, which is what usually happens), as the atom next door takes on the free electron, then passes one of its own on to get itself balanced and so on around the circuit– kind of like one of those card games where your neighbour passes you a card and you pass one to the person on the other side of you.
• This electrical energy can be transformed into another form, such as heat (heaters and ovens), light (computers, light bulbs, TV screens, etc), motion (kitchen and garage gadgets and tools) or sound (stereo equipment).

Solar panels have a few other names:

• Solar arrays
• Photovoltaic panels
• PV panels