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Solar Lamp Only $2

Solar Lamp

In some third world countries, when the sun goes down, there is no light for the people. If there is, it is usually a kerosine lamp that burn indoors. The light is useful, but some claim that one night of breathing in the fumes is the same as smoking 40 cigarettes. And to top it off, 20% of a family’s income every week pays for the fuel.

$2 Solar Lamp by LEDsafari
$2 Solar Lamp by LEDsafari

The folks at LEDsafari are doing some great work using a very simple method. They use a cell phone battery with the electronics removed, an LED, a switch and a small solar cell to build a low cost solar lamp.

Little by little their method is getting a bit more sophisticated. LEDsafari is now adding a diode to keep the battery from sending power to the solar cell and burning it up. Also, a resistor is added to limit the current the battery delivers to the LED so it lasts longer. Total cost is about $2.00.

There are some simple ways to improve upon these methods. But for now, this project has been a blessing for thousands of people. Without LEDsafari’s solar lamp program, many would be sitting in the dark or spending money just to breath unhealthy fumes. This just shows that something so small and simple really can make a huge difference in people’s lives!

LEDsafari Students
LEDsafari Students

Saving Money, Reducing Fuel & Increasing Health

The income savings and health benefits are obviously priceless. It is important to understand this isn’t a hand-out. LEDsafari holds workshops to teach people how to empower themselves by learning how to build their own solar lamp! Just look how happy those kids are in the picture up above. This is not just a technical skill, but a way to increase their self-esteem and build confidence in the fact that they can help themselves.

Support this project by telling your friends, sharing this page and visiting: LEDsafari

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Halbach Array 1.4 Pound Motor Delivers 7 Horsepower

Halbach Array Lightweight Motor

A classic three-phase 7 horsepower motor can easily be over 100 pounds and is designed to run around 1800 rpm. This higher power density motor delivers this kind of horsepower at almost 5 times the speed. It has different applications and windows of operation so it isn’t an apples to apples comparison. However, the developers do appear to win the bragging rights for the most energy dense motor commercially available.

Launchpoint Technologies Halbach Array Motor
Launchpoint Technologies Halbach Array Motor

Launchpoint Technologies website says, “With a total weight of only 1.4 pounds, this motor produces 7 horsepower at 8400 rpm with 95 percent efficiency. At 5 horsepower per pound, this motor has a higher power density than any other motor on the market.

There are countless applications for this kind of motor such as improvements in battery life in electric cars, electric bikes, electric-powered aircraft and the list goes on.

Halbach Array
Halbach Array

What makes this advancement possible is the use of the Halbach Array, which is a clever organization of the polarity of multiple magnets to create a very strong field on one side while almost totally negating the field on the other. Here is an old discussion on the Halback Array on Energetic Forum with some references: Halbach Array

Here is an early demo of the Launchpoint Technologies Halbach Array motor:

Halbach Array

A very interesting benefit of the Halbach Array is that it defeats Earnshaw’s Theorem which says, “states that a collection of point charges cannot be maintained in a stable stationary equilibrium configuration solely by the electrostatic interaction of the charges.”

For example, if you took a ring magnet and had another magnet on a shaft in side of that ring magnet, you wouldn’t be able to get it to stay right in the middle even if you spin it – if you were trying to create a magnetic bearing for example.

Halbach Array Magnetic BearingHowever, with the Halbach Array, you can. With the clever arrangement of the polarities of various permanent magnets, you can indeed get a magnet to spin inside of this field and maintain stability in the middle without it sticking to any particular spot.

Halbach Array Mangetic Bearing
Halbach Array Mangetic Bearing

Learn more at Launchpoint Technologies