Solar Outdoor Lighting Facts
Getting electricity to the lights in your yard can be a tricky business. High voltage wires have to be buried at least 18 inches deep to minimize the risk that they'll be run over by the lawn mower or dug up by the dog. Low voltage overcomes the danger to you. But the wires can still be endangered by garden tools, animals, etc. And if you run the wires too far, you'll experience voltage drop and dimming lights.
Solar-powered lighting provides an attractive alternative, especially for those remote areas of your landscape. They are powered by photovoltaic (PV) cells that gather energy directly from the sun. Their sensors tell them when the sun is down and turn them on automatically. They're environmentally friendly since they don't run off electricity that burns fossil fuels that generate carbon dioxide.
How It Works - Most PV cells are made from a highly purified form of silicon, the same element found in sand at the beach. These cells are arranged into two halves, one half with an excess of electrons, the other half with a deficit. The sunlight hits the PV cell, exciting the electrons on the side with the excess. They then flow to the side with the deficit. The result is electricity which metal leads siphon off and store in a battery until it's needed.
Those electrons are the only moving parts. This makes the PV cell quite sturdy and durable. Even though they are used outdoors, PV cells can last for twenty years or more.
Types - Solar landscape fixtures can address a variety of outdoor lighting needs. The smallest ones are also the cheapest. They provide a low intensity red light via incandescent bulbs. While they don't illuminate the surrounding area, they can outline a path or driveway to provide a bit of safety.
Slightly larger lamps make use of white incandescent bulbs. Or for a little extra light that can last a little longer, halogen bulbs may be your choice.
Even brighter than those are the 4 watt fluorescent lamps which provide the same illumination as a 16 watt incandescent. These can be used to provide a bit of illumination for gates or steps or wherever else.
The most powerful of all are the solar security lights that are attached to heat or motion sensors. Since these lamps only turn on occasionally, they can go for two weeks without sunlight and still provide light when called on.
Lastly, for those difficult shady spots, some solar lights come with a detachable PV panel. The panel may be placed in the sunlight where it gathers energy. The lamp may then be placed in the shady area to provide illumination there.