Back in April, startup company Bright Automotive unveiled its design for a plug-in hybrid light delivery truck. Now, we've had a chance to drive the prototype, briefly, just as Bright raised its electric range to 40 miles.

Our test vehicle was the only Bright IDEA van prototype built thus far by the Anderson, Indiana, firm. We were able to do precisely one low-speed loop on the roof of a Detroit parking structure.

Drives...like a hybrid

Due to an overnight charging problem, the vehicle's battery was largely depleted and it was running in range-extending mode with the engine on.

Bright IDEA plug-in hybrid delivery van, prototype

Bright IDEA plug-in hybrid delivery van, prototype

Smart IDEA plug-in hybrid delivery van prototype

Smart IDEA plug-in hybrid delivery van prototype

Bright IDEA plug-in hybrid delivery van, prototype

Bright IDEA plug-in hybrid delivery van, prototype

Bright IDEA plug-in hybrid delivery van, prototype

Bright IDEA plug-in hybrid delivery van, prototype

Bright IDEA plug-in hybrid delivery van, prototype

Bright IDEA plug-in hybrid delivery van, prototype

Remembering that this was an early development prototype, the Idea behaved like a hybrid, with a slight lag on acceleration and engine noise disconnected from any gain in road speed.

When forced briefly into electric mode, it ran as quietly as any prototype with a huge empty cavern behind the driver's seat is likely to run.

Bigger battery

The improved all-electric range--it's now 40 miles, up from the previously announced 30 miles--is due to a 13-kilowatt-hour battery pack, versus the 10-kWh pack specified earlier.

While that 40-mile electric range is the same as the 2011 Chevrolet Volt, also a series hybrid design, the Idea is likely to have a longer duty cycle as an urban and suburban delivery van.

With engine on, 36 mpg

After that, with the engine switched on to recharge the battery, the Bright IDEA returns 36 miles per gallon in range-extending mode. (Though Bright does note all range and efficiency numbers are based on an unloaded van.)

If its route covered 80 miles each day, the IDEA would run half on electric power and then half on gasoline. The last 40 miles would use about 1.1 gallons of gasoline, giving an effective total fuel efficiency of 70 mpg over 80 miles.

If the route were only 60 miles, though, the effective gas mileage would rise to more than 100 mpg. In either case, the Bright IDEA's fuel efficiency is as much as 10 times that of a conventional van driven in stop-and-go traffic.

Choosing an engine

The prototype we drove was fitted with a 2.0-liter Chrysler engine from a Dodge Caliber, but the company is now evaluating engines to specify as the range extender.

One possibility, according to Bright staff, is a future 1.6-liter engine now sold in Europe by General Motors, which the company plans to Federalize.

Fleet-user needs

Bright says it has developed the IDEA van in close consultation with fleet users, who are some of the toughest buyers in the market. The company faces the challenge that early lithium packs will be very expensive, though the vehicle qualifies for a $6,250 Federal tax credit.

Bright has consistently declined to quote a price, explaining that fleets look at costs differently. Our translation of that thought: It'll be expensive.

Closest competitor: Ford Transit Connect

The 3500-pound vehicle, built of aluminum and composite materials, carries a payload of 2000 pounds, and its cargo volume is 180 cubic feet.

Its closest competitor is probably the 2010 Ford Transit Connect small commercial van, rated at 22 mpg city / 25 mpg highway. The Transit Connect has sold surprisingly well in its first few weeks on the market, and Ford will offer an all-electric version in small numbers next year.

The IDEA offers useful fleet features like a passenger seat that folds down to form a work surface, complete with cupholder. The designers are targeting a drag coefficient of 0.30, equivalent to the lowest-drag car ever offered a quarter of a century ago.

Looking for low-interest loans

Bright has applied for up to $400 million in low-interest loans from the Department of Energy's Advanced Technology Vehicles Manufacturing program that granted loans to Nissan, Ford, and Tesla in June, with Fisker added in September.

So far, no decision has been made on the company's application.