With the black cloud of global warming threatening the planet, people are finally starting to seriously go green. But where is the global interest in green projects? It isn't like they can't be exciting, as new methods of harnessing energy are at the forefront of modern technology. What I am going to share with you here is not hopelessly high tech, but a very manageable project for anyone with the interest and patience.
Solar powered trikes have become very popular across the pond, and a wide variety can be purchased as kits and also as readily made vehicles. This one is designed to be built by hand, by anyone, in any suitable garage or garden shed!
The construction plan, provided at www.instructables.com, details the use of three Q-cell brand mono-crystalline solar panels pushing 21.8 volts peak at around 1.2 amps.
Using all three panels wired in series gives 66 volts peak, which is ample for charging the three 12 volt batteries, also wired in series, which are used to power a 36 volt brushless motor built into the trike's front wheel. Using some basic physics, power can be calculated as current times potential difference, which roughly equates to 61 watts nominal power and over 80 watts peak.
In practical terms this means the trike can reach about 18mph in good conditions with a range of well over 10 miles before the batteries begin to lose charge. This really isn't bad for a homebrew design, especially one that has so much area for further customisation.
For example it wouldn't take an expert to install a dynamo on one of the rear wheels to boost the charge once the trike is travelling at a steady speed.
I'll admit it isn't the fastest mode of transport in the world, using the conventional pedals alone will get you moving faster, however. Nevertheless, it can be seen as a step towards a brighter future. This little project proves that it is both easy and affordable to manufacture your own eco-friendly green machine, which you would be grateful for when a particularly steep hill comes your way.
When the trike is finished and you are whizzing about some small country lane with the trees beaming down on you from all sides, you might just want to stop and contemplate what else can be done in the future.
For a full step-by-step guide to building the trike, and also an extensive parts list, be sure to look at the instructables site.
Tom Wilson
See also: The Electronics Weekly focus on solar cells





Comments (3)
"For example it wouldn't take an expert to install a dynamo on one of the rear wheels to boost the charge once the trike is travelling at a steady speed."
No..... just an idiot!
Posted by Chris | July 22, 2009 12:17 PM
Posted on July 22, 2009 12:17
Dynamo - not necessarily an idiot, but using the motor as dynamo would make more sense if it's possible to do so.
It can be constructively used under the following conditions:
User pedalling (but would increase effort - tradeoff, only really of benefit if using motor as a hillclimbing/takeoff assist)
Braking or downhill running (regenerative braking)
In hilly conditions regeneration may substantially increase range which is usually seriously curtailed compared to flatland running.
To get an idea of _how_ curtailed, remember the batteries have to not only overcome rolling/drivetrain/wind friction as you do on the flat, but also provide an extra 10 Joules for every kg of mass raised one metre climbed.
Even a moderate 1/10 slope may take that 10 mile range down to less than 2.
This is the reason I had to give away the idea of using an electric motorbike for my daily commute. Intervening hills meant the range was only just enough to make the trip and if the batteries deteriorated for any reason I'd be sitting at the side of the road somewhat short of target.
Even so, this is a great idea if somewhat impractical for day to day use due to vandalism risk.
Posted by Alan Brown | July 22, 2009 2:06 PM
Posted on July 22, 2009 14:06
Such innovations truly need to be commended and encouraged. Of course it would be sometime before they get accepted and become the norm. But we can do our bit in making to gain acceptance more rapidly by using it ourselves and spreading the word around as it is a much greener way to commute. We maintain a global sustainability directory called the website of Climatarians, in which we list sites that feature such unique innovations.
Posted by Climatarians green community | December 2, 2009 12:16 PM
Posted on December 2, 2009 12:16