 |
 |
 |
 |
 |
|||
 |
 |
||
|
|
|||||||||
|
Practical SolarThis web site is hosted FREE by Servin Mervin
Solar energy is the great hope for the future for sustainable energy, with 1Kw of of energy falling on each square metre of ground in direct sunlight. Sadly just right now the reality is that it's too inefficient, too expensive, and it's possible that typical solar systems produce less energy in their life time than it takes to manufacture their component parts. The solar landscape is currently dominated by oil companies who are monopolising production, utilising solar as a marketing platform to convince the naive public that they are green, when in reality they are the actual producers of the very materials that are harming the atmosphere the most. Current solar technology hasn't advanced a whole lot. It still converts visible light to electrical potential, whilst remaining unable to convert light that is not visible e.g. ultra violet light. It's just not efficient. Solar power is useful in situations where it's not practical to supply power by other means. We see more and more solar power applications about us e.g navigation lights on water ways, but these applications have become suitable for solar because the efficiency of the load has improved. In the case of waterways markers, LED lighting technology has enabled solar to replace gas posered lighting systems through vastly reduced power consumption.
The Great Solar Hood WinkWhen is 100 Watts really only 80 Watts ? When it's a rating referring to a solar panel of course !! You never ever get quite the rated power out of your solar panel. The reason for this is not technical or du to inefficiency, but rather the way that the industry rates the panels, and it's pretty sly. You will only ever get about 80% of your panels rated wattage as usable electricity from it. Most DC electrical systems operate at a voltage of either 12V, 24V, or 48V, or some other crazy multiple of 6. Most solar panels have a rated voltage output of around 17 volts. It is at this rated voltage that their current is calculated to achieve their voltage rating The problem with this is that at 13.8 volts (a 12 Volt system under charge), the real power is 13.8*4.65= 64.17Watts. One way or another the difference is lost in heat (usually as heat) somewhere in your system. This is the great solar hood wink because you never quite get what you pay for, when the real cost of solar panels is a cost per watt of power output. There is a potential solution to this problem - a switch mode regulator (inherently 10% inefficient) could be used to lower the voltage. The problem is that in spite of my research I still haven't found one on the market as yet.
|
