A new outdoor lighting technology called “lunar-resonant streetlights” is coming that will enable streetlights to respond to ambient moonlight which dims and brightens each month in line with the moon’s phases?
The beauty of this technology is that on clear nights when the moon is full, streetlights could turn off completely. This approach could save as much as 80–90 percent of the energy used for streetlighting.
Equally, the technology could be used for domestic outdoor lighting applications to bring back the experience of natural moonlight and a star lit sky to residential areas.
The concept is a small and simple intervention but it could impact light pollution and energy use on a global scale. It can be used to retrofit existing streetlights with dimmable LED bulbs and a highly sensitive photo-sensor cell that detects and respond to moonlight.
Now prepare to be amazed - research indicates that streetlights consume 38 percent of the electricity used for lighting in the United States. This generates close to 300 million tons of carbon emissions a year!
Streetlights are also the top source of light pollution that prevents most Americans from seeing stars at night. Switching to dimmable LEDs and using more responsive sensor cells could save the bulk of that wasted energy.
Incredibly however, streetlights became a convenient way in the 1930s to off-load excess energy from the grid at night, when power demands dropped significantly. It was this intentionally inefficient system determined the norm for nighttime outdoor lighting levels.
This wasteful standard has never been revised, even though off-loading electricity ended in the 1970s. What we now assume is a safety measure is in fact a forgotten leftover of an obsolete energy practice.
Current lighting standards are based on comfort levels and perceptions regarding nighttime safety, but since the off-loading started in the 1930s, people have become accustomed to the feel of brightly lit streets and parking lots. But ironically, studies have shown no link between outdoor lighting intensity and crime or accident rates. In fact it’s actually more dangerous dealing with the drastic variation in light levels within an urban area because your eye does not have time to adjust and so your vision is impaired.
So watch out for this technology appearing for domestic outdoor lighting application. You can follow its progress via Civil Twilight.
As solar panels become smaller and cheaper, they are becoming more popular for landscape outdoor lighting applications. The main benefit is that solar powered lights do not need any wiring and are therefore simple to install and can be easily moved around to different spots.
The major downside is that they are dependent upon sunshine to work. If you have a series of cloudy days, the lights will only work for a short period, or perhaps not at all, before the battery runs out
How solar energy panels work
A solar energy panel collects energy from the sunlight and converts it into direct current (DC) electricity. Two oppositely charged slices of silicon are placed together below a piece of glass and as the protons in the sunlight knock the negatively charged neutrons away from the silicon the electric field created by the two adjoining pieces of silicon attract the neutron. Small pieces of wire catch the neutrons and when they connect they create direct current electricity. The wires connect to an inverter that changes the direct current (DC) into alternating current (AC) that we use in our homes.
Solar panels, known as photovoltaic (literally meaning ?electricity from sunlight?) are placed on the roof of your house, the roof of your garage or even as stand alone panels in your garden. Government grants are freely available to help pay for the panels and installation so do a little research and find out what you?re entitled to.
Domestic uses for solar panels.
A quick glance around your local gardening or home improvement store will show you that the amount and quality of solar powered goods are increasing. Garden lighting, water features and much more are now readily available powered by the sun but there really is so much more that solar power and solar panels can offer. If you?ve got a swimming pool you can heat that, or you can heat your hot water boiler with only a couple of solar panels or, alternatively, you may be considering powering your entire house with the rays of the sun.
PV roof tiles are not only available but also much more affordable than you probably think. If it?s time to replace your roof or you?re considering having it retiled for any reason then PV tiles are a much more viable alternative and after a year or two they will have undoubtedly made up the slight increase in cost you may face for the initial purchase and fitting. You need very little room in your house and fitting a grid tie system means you can sell surplus energy to the grid; all in all if you have full roof solar panels you can expect to reduce your annual energy cost by 75% to 100%. That?s a big saving, especially if you were only considering solar in order to try and do your bit to save the environment.
Can I buy solar panels anywhere?
Most electronics stores and garden or home improvement stores or will stock solar powered goods at the very least; find the right store and they will sell everything you need. If you don?t know what you?re doing with electronics it is highly advisable that you seek professional guidance, and a quick search on the Internet or a flick through your phone book will find several distributors and fitters of PV tiles and grid tie systems.
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For more more information about solar energy panels please visit http://www.alternative-solar-energy.com
Source: ArticleTrader.com