The first silicon solar cell was built in 1954, which gave us the ability to harness the almost limitless energy of the sun. True to our human nature, we have progressed in leaps and bounds to create portable solar power.
There’s more to solar panels than meets the eye: they all may look similar – but here are a five facts that you might not have known about solar.
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1. Different cell technology
There are three types of cells you can get in solar panels: poly-crystalline, monocrystalline, and amorphous cells. Poly and mono cells are typically found in rigid panels. All crystalline panels lose a small percentage of output as temperature rises above 25ºC, although mono cells do this to a lesser amount than poly cells. Amorphous cells on the other hand, do not suffer from this until uncomfortably high temperatures are reached (in which case you would probably be inside anyway).
Crystalline cells don’t perform as well as amorphous cells in partial shading and must be as perpendicular to the sun as possible to achieve their best performance.
So there is a hierarchy of cell technology:
Although they require twice as much surface area to obtain the same power output as mono, they are more flexible and can handle higher temperatures
A step up from poly cells, cells can be smaller in size
Less efficient than mono cells, require
larger surface area for same output
2. Shopping for solar panels is a bit like shopping for a diamond
When comparing like for like, monocrystalline cells are more efficient than poly-crystalline cells since they are made out of the highest grade silicon. You can also get different quality monocrystalline cells, for example the REDARC solar blankets feature the latest technology in monocrystalline cells – SunPower® cells. Compared to standard monocrystalline cells, SunPower cells are designed to reduce cell failure from corrosion and breakage. Their cells feature no gridlines, a solid copper backing and thick connectors for high efficiency and they also have in-built protection against partial shading (e.g. leaf falls on a cell). This results in consistent power output compared to standard monocrystalline cells where solar panels will lose output or, in some cases, stop working altogether if a panel is partially covered. Amorphous blankets, although requiring more cells for the same output as monocrystalline cells, are able to compensate this for a variety of factors. They’re lightweight and more flexible: you can throw them on top of your car, lay them on the floor or hang them up and they will still perform well. They also perform better in low light conditions as they are designed to capture the full spectrum of light (compared to conventional mono and poly cells). The bottom line is, you get what you pay for. Whether you buy a diamond from your mass-production jeweller or from a more bespoke outlet, you know the quality you’re getting. It’s the same with solar panels. The cheapest option usually means the cells are of low quality and subject to breakage, low efficiency and early failure.
3. Built to tour around our country
Mono and amorphous cells are the choice when it comes to bearing Australia’s harsh conditions. Panels need to be built to be able to withstand the corrugated tracks of the Outback and not fall apart on the first dirt road they come across. Monocrystalline fixed panels are designed with highly-efficient cells and protected with tempered glass coatings and sturdy aluminium frames. Because Australia is so big and has various ambient conditions, solar panels will perform differently depending on location and how much sunlight you are getting. Useable sun hours can vary in Australia from 11 hours in Karratha to just five hours in Hobart. An amorphous blanket is ideal for travelling as it is able to perform better in lower light conditions. In addition, it is less affected by minor partial shading than a monocrystalline panel.
4. A solar regulator is required
A solar regulator with a solar panel is like peas and carrots – they just go together, and they need to go together. Solar panels typically supply between 16V and 25V. And if that much goes into your battery, what’s going to happen? A fried battery! A solar regulator ensures that the correct charge is supplied. It protects batteries from overcharging and appliances against getting too much voltage. Having a high quality regulator is a must. Regulators feature multiple levels of protection including ‘over temperature’, overcharge and reverse polarity.
5. A mix of fixed and portable panels is key
Having a solar panel fixed to your caravan means you can take advantage of sun and charge your batteries while you’re on the move. A solar blanket enables you to set up camp in a shady area but still get the most out of the sun. Having a mix of both means you won’t be losing out on either.