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"This bus employs the most efficient hybrid architecture available in the world today, and is the first step in a larger GM initiative," said Tom Stephens, group vice president of GM Powertrain. "You get low emissions, great fuel economy, smooth and quiet operation, but one other thing is acceleration," explained Stephens.

СThe hybrid system combines an 8.9-liter Caterpillar diesel engine

with two 100 kW electric motors, and can deliver up to 60 percent better fuel economy than a traditional diesel bus. The GM hybrid buses produce much lower hydrocarbon and carbon monoxide emissions than conventional diesel-powered buses. In addition, particulate emissions (tiny pieces of soot and dust) are lowered by 90 percent and nitrogen oxide (NOX) emissions are lowered by up to 50 percent.

и system, whichбАcaptures and stores braking energy. "When you get into a

Another advantage of hybrid technology is a regenerative braking

hybrid system like this . . . every time you brake to a stop you convert that braking energy into electricity and store it in the battery, so the next time you accelerate you can use that braking energy to accelerate the bus," explained Stephens.

In addition to the fuel savings and emissions improvements, the GM Hybrid Transit Bus has operational sound levels equivalent to passenger cars. Metro Transit also expects the new buses will result in significant savings in maintenance costs.

saving up to 32,000 quarts of oil perДyear, plus labor and disposal costs. In a conventional bus, when you go to drive away you hear the diesel

Jim Boon, vehicle maintenance manager for Metro Transit Division of King County, told MSN Autos that they have not made any operational compromises nor any changes to the infrastructure to accommodate the

new hybrid buses. "This bus just walks on and goes to work," said Boon,

who expects to be able to extend oil-change intervals in the hybrid units, И

engine rev up and you get the noise and vibration, then you feel a strong jerk when it shifts into second gear.

"This bus is totally different," explained Stephens. "When you go to

drive away you hear next to nothing. The electric drive system augments the torque required to drive away and helps the diesel engine so you get a nice, smooth, quiet drive away and there are no shifts whatsoever; it is totally smooth, more like light-rail transportation as opposed to what you conventionally think of with bus transportation."

GM says that the hybrid system being used in the hybrid transit buses today will be scaled and transferred in full-size sport-utility vehicles and

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full-size pickup truck in the next few years. "These buses are incredibly significant for us," explained King County Executive Ron Sims, "We wanted a 21st century bus with lower operation and maintenance costs that wouldn't be dependent solely on petroleum-based products. We wanted a bus that would literally improve our air quality in a very significant way, and we wanted a bus that is a complete technology."

"The public wants clean air and public transportation is a key component of that," Sims concluded.

иGreen may be the new red, white & blue – but when you're talking wheels, how about fun? Or cool? The folks at Brammo Motorsports may be on to something.

бА protector. It's called the Enertia, anДelectric motorcycle so slick it couldn't

The Ashland, Oregon-based manufacturer – the same collection of motorheads responsible for bringing the road-rocket Ariel Atom to U.S. shores – have decided to confront the global-warming frenzy with an actual product.

A fun and efficient product. One that makes the similarly twowheeled and battery-powered Segway look like an environmental pocket

be cooler if it were frozen.

To create the Enertia, Brammo harnessed its enthusiast heart and ma- terial-science expertise to a global sensibility. By approaching carbon emissions from the perspective of true driving enthusiasts, the goal was to provide a practical product that hits on multipleИlevels: environmentally sound, sharply engineered, cutting-edge materials, fun to own and look at.

The Enertia is a clean-sheet design, conceived from day-one as a two-wheeled, zero-emission, fully electric conveyance (it is not a "hybrid"). Its central structure is a carbon fiber monocoque, which serves as both the motorcycle's chassis and its battery tray. Machined 6061-T6 aluminum bits for the bike's threaded hard-points (footpegs, swingarm, etc.), are bonded to the carbon fiber structure – a race-bred building technique. Though exceptionally stiff, the entire chassis weighs a mere 16 pounds.

Unlike your typical motorbike, the Enertia flops the engine/fuelstorage ratio. A typical motorcycle is dominated by its centrally mounted engine, and capped with a small gas tank. With the Enertia, the engine is an

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alternator-sized electric motor mounted at the bottom of the chassis just ahead of the rear wheel. The motor is directly coupled to the rear tire via a chain and sprocket.

Fuel storage for the Enertia consists of six 12-volt lithium-phosphate battery packs. These modules (about half the size of a traditional car bat- Сtery), are mounted inside the upper and lower channels of the H-shaped

carbon fiber chassis – three on top, three below. Brammo worked closely with Texas-based Valence Technologies on the application of the lithiumphosphate cells, which unlike lithium-ion or lithium-cobalt, are exceptionally resistant to combusting, even if the batteries are impacted or punctured.

и cal outlet. TheбАEnertia will reach an 80-percent charge in two hours, and be

Beneath a small lid where you'd normally fill up a motorcycle with gas is a connection to recharge the bike from any regular 110-volt electri-

fully recharged in three. Most cell phones don't even charge that fast.

The 86-pound battery package forms the majority of the Enertia's mass, and at 275 pounds it is extremely light for a street-going motorcycle. It feels even lighter, thanks to an exceptionally narrow profile – only 12.5 inches between your knees – and a low "moment of inertia." This is the effort required to flick the bike back and forth, which in the case of the Enertia is reduced because the main heft of the bike (the batteries) is concentrated along the bike's centerline.

The Enertia's power ratings (12Д-25 horsepower, 17-34 lb-ft of torque) make it comparable to a Kawasaki Ninja 250 in terms of horsepower, but the electric drivetrain provides double the amount of torque (the force that gets you moving), in a package 30 pounds lighter. At the 100-percent power setting, Brammo claims a 0-30 mph time of 3.8 seconds – plenty of

The power level of the Enertia is user-selectable from 40 to 100 percent. This determines how fast you draw current from (i.e. discharge) the batteries. This adjustability allows you to trade more power for decreased range (if you have a shorter commute), or to make the machine more docile

power for the urban jungle.

A small Enertia logo in the gauge cluster glows red, yellow or green depending on the power draw, to help maximize efficiency. I kept it mostly in the red – which had me outpacing traffic and running near the Enertia's 50-mph top speed (easily exceeded on any downgrade) – in hopes of gaining a realistic feel for its operating range.

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After a completely uneventful, serenely quiet and emission-free 30mile loop around Portland, (where it truly felt as if I were driving in the future), we returned the bike to Brammo with the gauges still showing 30 percent battery range available.

For those looking to make a lifestyle change, or for a cool "green" Сmachine to get around town on, few options exist that can compete on so

many levels. Unless you're rollin' with a crew who can't leave the house without a pocket protector, what says lust for life and love for the big, blue marble better than an electric motorcycle?

и бАby Larry E. Hall of MSN autos

V2G TECHNOLOGY ON PLUG-IN ELECTRIC CARS

OK, you're feeling really cool and smart with your purchase of a plug-in hybrid-electric vehicle (PHEV). Your daily round-trip commute to

work is barely 30 miles so, recharging the batteries overnight gives you some change back from a ten-dollar bill for the weekly cost of electricity. Plus, since you drive entirely on electric juice, there are zero emissions coming out the tailpipe.

Wowzer, what a feeling! But wait, there could be more euphoria in the offing.

What if the local power companyДwas willing – maybe even anxious

– to pay you to draw some of the stored energy from your PHEV's batteries while it was parked during the day? Hey, that would reduce the cost of operating the car even more.

That's exactly what Professor Willett Kempton of the University of Delaware and his colleague Dr. Steven LetendreИfrom the Green Mountain College in Poultney, Vermont, came up with in 1966.

Called vehicle-to-grid (V2G) technology, the idea is to take advantage of the electrical storage capacity in the vehicle's battery during hot afternoons when demand is highest and most costly to avoid blackouts. During these periods, energy is worth several times more than overnight when vehicles recharge. It is also possible to provide power to a home or businesses on occasions of high electricity demands to avoid high energy prices and help prevent outages.

Kempton and Letendre's idea isn't just a theory presented in a technical journal. In April, California utility Pacific Gas and Electric Company showcased the first-ever utility V2G technology demonstration. The proto-

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type PHEV was a traditional Toyota Prius with an added Lithium-ion battery. PG&E reversed the flow of energy from the vehicle back to an electrical outlet, then ran several lights and appliances to show how V2G could benefit its customers.

The really big potential of using V2G, however, will come from in- Сtegrating the technology with renewable energy and thereby reducing harmful emissions. During times of maximum demand, electrical utilities have to buy power from expensive and less efficient fossil fuel power gen-

erating sources.

иPHEVs will charge their batteries at night when energy is inexpensive and is generated with a larger percentage of renewable resources. When demand is high the next day, instead of turning on a fossil-fuel based generator, the utility can purchase the renewable energy stored in the vehicle batteries.бА

There are numerous hurdles in the path of V2G, not the least of which is the cost of developing and integrating the technology into the automotive and electrical generation industries on a wide scale. But, because V2G has the potential to radically change both the utility of vehicles and the ability of cities to meet peak electrical demand with significantly lower costs while reducing harmful emissions, don't be surprised if the hurdles are overcome sooner than later.

http://editorial.autos.msn.com

FIELD EFFECTДTRANSISTOR

In 1945, Shockley had an idea for making a solid state device out of semiconductors. He reasoned that a strong electrical field could cause the flow of electricity within a nearby semiconductor.ИHe tried to build one, then had Walter Brattain try to build it, but it didn't work.

Three years later, Brattain and Bardeen built the first working transistor, the germanium point-contact transistor, which was manufactured as the "A" series. Shockley then designed the junction (sandwich) transistor, which was manufactured for several years afterwards. But in 1960 Bell scientist John Atalla developed a new design based on Shockley's original field-effect theories. By the late 1960s, manufacturers converted from junction type integrated circuits to field effect devices. Today, most transistors are field-effect transistors. You are using millions of them now.

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