Zetalux LED Light Bulb

Update: See our latest post on LED Light Bulbs For The Home.

I recently had the chance to test two state-of-the-art LED light bulbs from EarthLED. LED bulbs have many advantages over incandescents and compact fluorescent: they use very little power, they last 10 years or more, and they contain no hazardous substances. They are also tough: they can be dropped and turned off and on repeated without damage, they can operate in very cold or warm temperatures.

LED bulbs can also save you money in the long term, because an incandescent bulb requires about $300 worth of electricity over ten years of use. The LED bulbs cost $40 (for the 60 watt equivalent Zetalux) and $50 (for the 100 watt equivalent Evolux), and their cost to run over ten years is about $38.

The Zetalux

The first EarthLED bulb I tested was the ZetaLux LED (pictured above). This bulb produces a pleasing warm white light.

Until recently, LED bulbs were only capable of producing a stark, cool white light, so I was happy about the color temperature of this bulb (it’s rated at 3000K). The bulb didn’t need to warm up like a compact fluorescent, and there was no flickering at all.

The Zetalux uses a CREE LED engine and features a high CRI or Color Rendering Index (75 for cool white and 80 for warm white). The bulb is rated at 7 watts. However, when I tested it with a Kill-A-Watt meter it was drawing only 5 watts.

The warm white version of the Zetalux produces 350 lumens, and the cool white produces 450 lumens. Comparing LED bulbs and other bulb solely on lumens is tricky because LED bulbs tend to make better use of their lumens in recessed fixtures (see this page for more details). EarthLED says the bulbs are equivalent to a 50-60 watt incandescent bulb.

The Zetalux LED Bulb illuminating my hallway.

The Zetalux currently sells for $40. The bulb costs about $2 per year to run, assuming it’s left on 8 hours a day and the cost of electricity is $.10 per KWh.

The Evolux

The second bulb I tested was a cool white Evolux. This 13 watt bulb produces 1075 lumens, and according to EarthLED is equivalent to a 100 watt incandescent. This bulb is definitely bright — it illuminates my garage quite well.

EarthLED says the Zetalux and Evolux will become the first FCC and Underwriter’s Laboratory (UL) listed LED light bulbs on the market at the end of 2008. Both bulbs are RoHS compliant.

EarthLED will be releasing a dimmable version of the ZetaLux, and a new version of the Evolux in early 2009.

These bulbs are available from GoGreenSolar

The world’s largest wind turbine is now the Enercon E-126. This turbine has a rotor diameter of 126 meters (413 feet). The E-126 is a more sophisticated version of the E-112, formerly the world’s largest wind turbine and rated at 6 megawatts. This new turbine is officially rated at 6 megawatts too, but will most likely produce 7+ megawatts (or 20 million kilowatt hours per year). That’s enough to power about 5,000 households of four in Europe. A quick US calculation would be 938 kwh per home per month, 12 months, that’s 11,256 kwh per year per house. That’s 1776 American homes on one wind turbine.

The turbine being installed in Emden, Germany by Enercon. They will be testing several types of storage systems in combination with the multi-megawatt wind turbines.

These turbines are equipped with a number of new features: an optimized blade design with a spoiler extending down to the hub, and a pre-cast concrete base. Due to the elevated hub height and the new blade profile, the performance of the E-126 is expected to by far surpass that of the E-112.

WiredForStereo of The Way explains the operation of these new turbines:

[The E-126]… has no gearbox attaching the turbine blades to the generator, in fact, the generator is housed just at the widest part of the nose cone, it takes up the entire width of the nacelle to generate power more efficiently, and provide longer service life with less wear.

Also like small turbines, these have inverters instead of synchronous generators, that is to say, a separate controller that converts the wild AC generated into something the grid can use. This means the rotor can run at more optimum and varied speeds.

Again like small turbines, this one does not shut right off at a predetermined speed due to gusts or just very high wind speeds. It simply throttles down by turning the blades slightly away from the wind so as to continue to generate power though at a lower production rate. Then the instant the wind is more favorable, it starts back up again. Many smaller wind turbines do something similar except have no blade pitch control, they use a technique called something like “side furling” where the whole machine, excepting the tail, turns “sideways” to catch less wind but continue operating.

Money, why else? Big things are cheaper per unit production. If you have 3 2 MW generators, you have to have three (at least) cranes to put them up, build three foundations, have to maintain three machines, and have three times the parts to fail. If you have one, it is larger and more expensive in itself to move, but not as expensive as having to move three smaller ones.

I don’t understand how people can be so concerned about birds becoming mush with modern wind turbines, especially ones this big. It only turns at 12 rpms. That means it takes five seconds to complete one revolution. That is slow but this is much bigger and easy to see compared to the whirring blades of old. The Altamont Pass turbines gave wind turbines such a bad name because they were built in the middle of the natural habitat of rare birds, the turbines were the small fast spinning type, and they were built using lattice towers, the kind birds love to nest in. These are slowly being replaced and all of the new ones are of the slower rotating kind. In the end, it comes down to this. Stationary buildings and moving cars kill literally millions of times more birds than wind turbines. And things like the Exxon Valdez spill kill millions of everything. So let’s go with the best option.

^{A graph of the World’s Largest Wind Turbines.}

This is a great innovation — the streets of Europe could soon be lit by "solar trees". These self-contained streetlights could save cities energy and money too. Unlike regular streetlights, they do not require costly underground wiring to install, and they are immune to blackouts. Designed by Ross Lovegrove, the lights have 10 solar panels arrayed at the top of tree-like branches, which charge built-in batteries. The batteries then power LEDs for illumination. Compared to conventional streetlights, they emit much less light pollution, because LEDs generate a very directed light. The trees also incorporate light detectors! So the lights automatically turn on sunset and off at sunrise.

The solar trees went on display for four weeks in October on a busy street — the Ringstrasse — in Vienna, Austria. They were able to provide enough light during the night-time even when the sun did not show for as much as four days in a row. The director of the program, Christina Werner said. "Someday soon solar trees could well be the main form of street lighting in Europe."

Putting solar powered LED light systems on trees would cut down on the carbon emissions and also slash the bills of local authorities, she said.

Street lighting consumed 10 percent of all the electricity used in Europe in 2006 or 2,000 billion KWh, and resulted in carbon emissions of 2,900 million ton.

The use of more energy-efficient lighting in the Austrian city of Graz, with a population of almost 300,000 saved the city 524,000 KWh of electricity and 67,200 euros [US $96,800] in 2005.

Via: RenewableEnergyAccess

Power Consumption: 277 kWh per year
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Power: 120 V AC
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