You can connect solar cells from cheap LED yard lights to power a CPU fan. It works in bright light. Take a look.
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Solar Light Casing: The casing of the solar lights can be manufactured in many different materials; brass, bronze, copper, stainless steel, durable plastic, etc. Even the durable plastic is strong enough to last absolutely years. Any casing should be wiped down with a damp cloth periodically to remove layers of dirt.

Solar Panel: also called solar cells, or photovoltaic (PV) modular cells, which is a group of cells electronically connected and packaged in one frame. Solar cells are created with silicon which has impurities added to it, to allow electrical current to pass to the diode, also known as doping. Silicon crystals are expensive to make and the major expense of the solar light. The solar panel converts sunlight directly into electricity, charging the NiCd or NiMH rechargeable battery, then transferred to the LED diode. Solar cells are wired directly to the battery through the diode, which prevents the battery’s current from flowing back through the solar cell at night.

NiCd or NiMH Rechargeable Battery: Nickel-Cadium (NiCd) or Nickel-Metal Hydride (NiMH) batteries are designed to operate from fully charged to fully discharged. An AA size NiCd battery produces about 1.2 volts, and can store a maximum of approximately 700 milliamp-hours. NiMH batteris are a type of secondary electrochemical cell similar to an NiCd. NiMH uses a hydrogen absorbing alloy for the negative electrode instead of cadmium. As in NiCd cells, the positive is nickel oxide hydroxide (NiOOH). A NiMH charging voltage is 1.4-1.6 volts per cell, and can have 2-3 times the capacity of an equivalent size NiCd. A good quality NiMH will generally last up to 1,000 nights.

Photoresistor Cell: Located on the exterior of the casing, sends input to the controller board that darkness is occurring.

Controller Board: Accepts power from the solar cell and battery. When the photoresistor indicates darkness to the controller board, the controller board activated the battery. The three-transistor circuit turns on the LED light.

Light Emitting Diode (LED): A diode is the simplest possible semi-conductor device, and allows current to flow in one direction, but not the other. Basically, a diode is a one-way turnstile for electrons. One LED emits roughly the same brightness as a 2 watt incandescent bulb. The tiny LED bulb fits into an electrical circuit and illuminates solely by movement of electrons in a semi-conductor material, and lasts as long as a standard transistor. There is no filament to burn out, which is why LED lights have a lifespan of 100,000 hours, which is over 25 years.

That is how solar lights work, very simple, very few components, and the energy to have light outdoors at night is supplied completely free of charge, by the sun.

Check out all of our Solar Lights products at www.NaturesSolarLights.com. Go Green!

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St. Petersburg

5/27/2008 – The switch was flipped on what is being described a the next wave in solar technology. The juice from those solar cells is being stored in a new kind of battery – one that uses vanadium suspended in a solution of sulfuric acid. It has freed Albert Whitted Park from the main electric grid.

What is being billed as the nation’s first Sustainable Electrical Energy Delivery System, was developed jointly by Progress Energy Florida and the University of South Florida.

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Solar yard lights are fast becoming popular with consumers revealing how very volatile consumer preferences could be. Going green is the concept involved and although sometimes, considered as a fad, going green concepts have taken over the world by a shock making advances in the market.

Note that many solar yard lights are sensitive to changes in environment and gets switched off automatically at dawn and gets switched on in the evening making life very easy for the people using the product.

They use the sun’s light to energize solar cells which store the energy in batteries and in turn produce light during hours of darkness. Solar powered yard lights work in the same way as any other solar lighting but differ in purpose – they are used. The current then sends energy to the power supply (rechargeable battery) which in turn energizes the lamp (LED). The efficiency (or light output) is based upon several factors such as cell capacity, lamp source, battery type and the PC board design.

The solar energy recharges the batteries during the day; at night the LED light turns on providing you with a beautiful light display to enjoy for up to 12 hours. This solar walkway light is easy to install, no cords or wires to fuss with. Every day solar cells collect energy from the sun and charge the rechargeable batteries included with each landscape light. At night, these lights will then turn on to provide illumination. A drawback is a site that is in complete shade all day may not get enough sun to properly charge batteries and for those few locations solar yard lights may not work. Check with a landscape expert, or even just places selling solar lighting to know how to assess a location for suitability.

Systems operate on just 4 AA batteries and the included 1.2V 1.200mA rechargeable battery. After nearly a year, the LED lights and the rechargeable batteries may still be going strong. They may show no sign of needing to be replaced.

With no wires to worry about, nor bulbs that burn out, you’ll find these will really brighten up your landscape! They feature clear LED landscape lights powered by a solar panel you can stake up to 14′ away. It comes with a flexible plastic ring that ranges in size from 6″ to 11″ in diameter and is very is to stake inside a pot or in a flower bed if so desired. Step lights and path lights are also common types of outdoor landscape lighting that look great and provide safety. By lighting the walkways and steps in the front and back of your home you can provide a safe area for people to walk on in the dark.

Whether you are accenting a driveway, lighting a pathway, or simply making your home come alive with nighttime lighting, solar landscape lights made from quality components offer the longevity and reliability you need. It pays to shop around because there is still a lot of inferior product on the market. Look for high output LED’s. Technology has arrived to the point that we are now able to get up to 83% of light from energy spent with LED’s. That makes for long-lasting light at high output. Remember, solar landscape lights are free energy from the sun. And you should look for units where you can replace the rechargeable batteries. There are a few indications that you can.

For landscape designers knowing the difficulty in running underground wire for intricate lighting designs, solar power comes in as a life saver. Imagine low to no maintenance lights that blend into the landscape and come on automatically, then go off automatically. It really pays to invest in quality lights for a worry-free installation. Most units will have written on them that you can change the rechargeable batteries, typically AA’s. But make sure you buy a high quality solar cell as well.

Higher quality solar landscape lights employ Siemens Mono-Crystalline solar panels. Mounted directly on top of the units, these high output cells recharge the Ni-Cad batteries quickly and efficiently, and last for years. Another consideration, especially in the northern parts, is the plastic casing. All quality lights are fully weatherproof not just from rain and sun, but cold winter nights as well. A few manufacturers incorporate stainless steel as well into their designs.

Look for solar cells that put out at least 3 watts. The better units will have ultra-bright LED lights that display at least 12,000 mcd. And make sure the unit you choose comes with high capacity Ni-Cad batteries. Most websites that sell these units will have all the specs listed so you can compare. You can also see the size and style of lights and think of how they would fit into your landscape. There are several styles which work great with wood decks and others that look wonderful amongst the plants.

Remember that these solar landscape lights will need to get at least 8 hours of daylight to charge the batteries, even though in full sun they will charge much faster. Consider where you are placing the lights as full, overhead sun is best, and many will not work well if constantly in the shade, or if they are only receiving early morning or late afternoon light. You can always change out the Ni-Cad cells for higher powered ones, but remember that they will take more light and longer time to recharge.