Light bulbs siphon a lot of juice out of the grid, which makes them perfect targets for anyone trying to conserve power. Compact fluorescents (CFLs) have been leading the charge, armed with mercury vapor and phosphor that emits far more light per watt than hot incandescent bulbs. But they’re toxic and expensive, so engineers are looking for alternatives.
Enter LEDs, light-emitting diodes. They can be twice as efficient as CFLs and 10 times as efficient as incandescent bulbs. But they’re expensive, complex structures of gallium nitride crystals, reflectors and even sapphires. Until now. Researchers at Perdue University have figured out how to make LEDs using good-old silicon wafers. The new process could mean LEDs that compete, price-wise, with CFLs and even incandescent bulbs. And the new LEDs are efficient—between 47 to 64 percent efficient. Compare that to an incandescent bulb’s paltry 10 percent and you can see how the new lights could save a ton of electricity.
That’s not all. LED manufacturer OSRAM has developed a new LED that’s significantly brighter than existing bulbs. They’ve managed to push 500 lumens out of a single 1-mm-square LED. To put things into perspective, a 100-watt incandescent bulb puts out about 1700 lumens. The new LEDs are also extremely efficient, cranking out about 136 lumens per watt. Again, a 100-watt incandescent only manages about 17 or 18 lumens per watt. OSRAM plans to put the new bulbs on the market within a year. Possible uses include small projectors, automobile lights and interior lighting for the home.
If that wasn’t enough, the startup Vu1 is producing a new type of light bulb altogether. They’re called ESL (electron stimulated luminescence) and they use electrons to directly stimulate a layer of phosphorus on the inside of a bulb. It’s the same technology that makes the old-timey tube TVs glow. The company claims that their bulbs emit about 40 lumens per watt. The light, they say, matches incandescent light in color and quality. The bulbs should be available in September 2008 for about $12 a piece. Not cheap, but on par with the price of a dim-able CFL.
So what difference will all these newfangled bulbs make? The US uses a third of its energy for lighting. Engineers at Perdue estimate that switching out incandescent bulbs could cut US energy consumption by about 10 percent.
Turns out that your average plasma TV sucks more electricity from the grid than those fancy new plug-in hybrid cars that are coming on the market. According to officials at the Electric Power Research Institute who were quoted in a recent Associated Press article, big-screen plasma TVs drain about four times as much power as plug-in hybrids.
Why should you care? It means that the U.S. power grid is capable of handling a few million plug-in hybrids without blowing its gigantic, irreplaceable fuse. The logic goes something like this: Consumers have purchased millions of big-screen plasma sets during the past few years. They’ve all plugged them in and probably leave them on for HOURS each day. Plug-in hybrids, on the other hand, will likely be plugged in during off-peak hours, late at night while most people sleep and when the grid isn’t being taxed.
The grid may be able to handle plug-in cars, but we’ll still need to generate more electricity to meet their demands. Hopefully that energy will come from solar and wind rather than coal-fired power plants.
A new glass developed by engineers at MIT can soak up sunlight and divert it to tiny photovoltaic cells along its edge. The sunlight-collecting glass is so efficient and inexpensive to manufacture that it could make solar power as cheap as coal power, the engineers say.
The glass would replace the lenses and mirrors that typically focus sunlight in photovoltaic systems. It works like this: Each pane is coated with a special dye that sucks up light and then channels it through the glass to small solar cells along the panes’ edges. Researchers have created several tints of the dye, each one capable of capturing a particular wavelength of light. It’s an important development because some wavelengths, or colors, of light produce more energy than others. High-frequency ultraviolet light is supercharged while lazy infrared yields little juice.
The researchers have stacked different panes of the glass, allowing a solar system to absorb several wavelengths of light. Using two panes, they say, nearly doubles the efficiency of the system. The panes are also good at sucking up indirect light, which means they don’t need to be mounted in expensive motorized sun-tracking apparatuses.
Marc Baldo, a lead member of the team, says that the panes could replace windows in homes and would be much more effective on rooftops, hilltops, or anywhere the sun shines. His team is testing several different combinations of the glass and hopes to produce large-scale solar collectors soon.
BMW is equipping 500 Minis with electric drivetrains for use in California. Company officials say they’re using the hip hatchback to test a few different electric powertrains. No word on exactly when the electric Minis will be available to the public, but I guarantee they’ll be a smash hit.
And still, the question hangs in the air like dirigible ready to burst into flames: Where are the Big Three’s electric vehicles? And don’t talk to me about the Chevy Volt, because there’s no way it should take one of the world’s largest car companies this long to develop a feasible electric car.
Google is great for driving directions, but not so great for bicyclists. Plug in an address and the maps app will likely funnel you through major thoroughfares choked with traffic. Take your bike and you’ll be sucking exhaust fumes, dodging taxis and delivery trucks and you might end up as a smear on the blacktop. The Google Maps Bike There Team wants to change all that. They’re petitioning Google to include a “Bike There” option that highlights bike lanes and back streets on a route. If you ever ride your bike in a big city, you’ll appreciate their efforts. Stop by and sign the petition:
A team of photochemical cooks at the Ecole Polytechnique Federale de Lausanne in Switzerland have whipped up a batch of inexpensive solar cells that could revolutionize solar energy. The “Dye-sensitized Solar Cells” use dye and an electrolyte solution to harness solar radiation to make electricity. The components are sandwiched together to form a flexible film that’s durable and long lasting.
Professors Michael Grätzel and Brian O’Regan invented the solar cells in 1991, but only recently developed an easy, low-cost way to manufacture them. So how do they work? The cells consist of a porous film of white, nanometer-sized titanium dioxide particles covered in a dark dye. The film is suspended in an electrolyte solution. When sunlight hits the dye, it injects an electron (negative charge) into the titanium particles.
Grätzel and his team have tweaked the manufacturing process, nixing the volatile organic solvents that typically make up the electrolyte solution in favor of a mixture of three salts. The bottom line: Dye-sensitized cells that can be made on the cheap without harsh solvents.
The new salt-based dye-sensitized cells have an efficiency of about 8.2 precent, a little more than half the efficiency of silicon-based photovoltaic cells. No official word on cost, but Grätzel and friends claim that their panels will be considerably cheaper than traditional solar cells. They should also last more than 10 years, says Grätzel.
Volkswagen’s 1-liter concept car has been winding its way through the twists and turns of the automotive news back roads lately. British auto mag Car has reported that the 600-pound streamlined fuel sipper will go into production in 2010, sporting a hybrid diesel drivetrain and sequential motorcycle-style gearbox. The original concept ran a one-cylinder, 1-liter petrol engine wrapped up in a carbon fiber body. The microcar features tandem seating like a fighter jet, but performance promises to be less than stellar.
The fact that small, fuel-efficient cars are making a comeback fills my heart with a warm fuzzy feeling that’s not unlike the buzz one gets from huffing gasoline fumes.
San Jose powerhouse Nanosolar has improved the efficiency of their printable solar cells, made from nanoparticle ink. The company now claims it can pump out enough solar panels every year to harness 1 gigawatt of power from the sun. Still not enough to power the Flux Capacitor (1.21 GW), but it would put a considerable dent in U.S. power usage. The typical U.S. home consumes about 8,900 kilowatt hours per year.
We spend a lot of time and energy trying to keep light out of our homes. When the sun blazes, we pull the shades, blocking sunlight that would normally turn our dwellings into sweltering greenhouses. Designer Shelia Kennedy believes that instead of deflecting all that energy, we could harness it. She’s invented “solar curtains,” sheets of flexible fabric with imbedded thin-film photovoltaic solar cells.
The designer and her team at KVA Matix have also sketched a house that can theoretically nab up to 16,000 watt-hours of electricity using the curtains. They call it the “Soft House.” The home hasn’t been built yet, but the photovoltaic curtains are in development.
AeroVironment, Inc.’s new modular wind turbines crouch on rooftops like whirling mechanical gargoyles, providing green, grid-free power for anyone who can afford them. The super-efficient turbines generate electricity at low wind speeds—about 5 mph—and can withstand wind speeds in excess of 100 mph. Each turbine weighs about 200 pounds and is, according to AeroVironment, easy to install. The company also claims that the turbines are relatively quiet.
A six-kilowatt starter system is currently available for commercial applications, but the amount of power generated by wind turbines varies greatly. Just like the wind.
AeroVironment also makes UAVs (Unmanned Aerial Vehicles) that are used for scientific research and military reconnaissance. A third division deals in power processing equipment for AC and DC power grids.
I definitely wouldn’t mind having a few dozen of these latched to the eaves of my apartment building. They would pay for themselves within a year and after that: Free juice for all.
