Germans create ‘free-piston’ multi-fuel engine that could answer EV range-anxiety issues

By Nick Jaynes March 17, 2013

piston-free generator

The Germans never cease to amaze us.

A group of scientists at the German Aerospace Center (DLR) have developed what they called the “free-piston linear generator” or, in German, the “Freikolbenlineargenerator.”

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In distinctly German form, the name is an entire sentence squished into a single word and not a satirical joke as we had hoped. The ingenious electricity generator is small, lightweight, and ideal for a range-extending application in an electric vehicle – and who knows what else.

piston-free generator close up

Comprised of two pistons inside a single cylinder facing one another, the pistons are fired simultaneously; the kinetic energy of the combustion is used to generate electricity. The opposing boxer-type movement of the pistons also means the engine offsets much of its own vibration for smooth operation.

More tech details and a concept video (in German) are here

In place of a traditional crankshaft and connecting rod, there is a gas spring behind each piston. This gas spring can be used to adjust the compression ratio on the fly. The ratio and combustion chamber size can be adjusted so minutely as to accommodate movements down to one tenth of a millimeter. This allows the piston-free generator to run anything from gasoline to diesel to natural gas to hydrogen.

piston-free generator in car

This sort of flexible electricity generation makes the free-piston generator perfect for electric cars that require a range-extending onboard generator. The Chevrolet Volt, for example, has a 1.4-liter inline four-cylinder gasoline generator that fires up after the initial 38-mile all-electric range is depleted.

Right now the free-piston generator only exists on a bench in Germany but we wouldn’t be at all surprised if some big-name automaker jumps all over this technology as it could be a small, lightweight solution to many EV problems.

We’ve always joked that the Germans were magic. With the unveiling of this “free-piston” generator, we now know they are.

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Cars

Fiat 500e EV customers will get free rental cars to ease range anxiety

From Day One, electric cars have been hindered by “range anxiety.” The average electric car simply can’t travel as far on a single charge as the average internal combustion car can on a single tank, and it takes much longer to charge than it does to refuel.
Some car companies are trying to solve the problem with engineering, but that could take awhile. Fiat has a much quicker solution: give EV drivers a second car.
Fiat is rolling out the 500e in California this summer, and it will offer free rental cars to all of its customers. The program, called ePass, gives owners access to an Enterprise rental for 12 days a year, during the first three years of ownership.
“We know we’ve got a great car,” Fiat North America brand head Tom Kuniskis told Automotive News (sub. required), “but I still can’t get a guy to New York to visit his grandma for Easter.”
The strange thing about all of this isn’t the idea of someone driving cross-country for an Easter family visit, it’s that Fiat would put its customers in someone else’s car.
It makes more sense when one remembers that Fiat didn’t really want to build the 500e in the first place. At the car’s Los Angeles Auto Show unveiling, Fiat CEO Sergio Marchionne said California’s Zero-Emission Vehicle mandate was the main impetus behind the 500e.
The 500e has a 111 horsepower electric motor and a 24-kWh lithium-ion battery pack. They can return an EPA-rated 87 miles of range.
So cynicism is the culprit, or is it? BMW will also offer rentals when its i3 electric city car goes on sale early next year. BMW has sunk a lot of its reputation into this car, which is supposed to demonstrate several important new technologies.
However, even BMW’s best couldn’t squeeze more than 100 miles of range (projected) out of the i3, so the company decided to go with a backup plan.
Offering someone another car isn’t really a solution to range anxiety, or the environmental issues EVs are supposed to solve. It will just make the lives of those that believe some electric motoring is better than none more comfortable.

Cars

Volkswagen ‘e-up!’ EV debuts with 93-mile range and trick charging system

Volkswagen is ready to launch the production version of its e-up! electric car.
VW will be showing the tiny EV at its Annual Press and Investors Conference in Wolfsburg, Germany before a public debut at the Frankfurt Motor Show in September.
The e-up! is based on Volkswagen’s up! city car, a tiny hatchback that shares motorcycle parking spaces with the Scion/Toyota iQ and smart fortwo. Unlike those fashion accessories, the up! is available with four doors, making it a true four-seater.
Motivation comes from an 80 horsepower electric motor and 18.7-kWh lithium-ion battery pack. Volkswagen says the e-up! will do 0 to 100 kph (0-62 mph) in 14 seconds and reach a top speed of 84 mph. So the e-up! isn’t really a Tesla Model S competitor.
Still, the VW wouldn’t embarrass itself in a slow-motion drag race with the equally small Mitsubishi i-MiEV, which does 0 to 60 mph in 13 seconds and has an 80 mph top speed.
Unlike its performance, the e-up!’s range should impress. Volkswagen says it will go 93 miles on a charge, a big increase over the 80-mile range quoted in early reports. It also eclipses the Nissan Leaf’s EPA-rated 74-mile range.
However, since the e-up! wasn’t tested according to the EPA methodology, that number could drop if the e-up! ever makes it to the United States.
The e-up! also comes with a nifty Combined Charging System (CCS). Like the chargers currently available for the Leaf and Model S, CCS can do a 30-minute quick charge, in this case restoring 80 percent of the battery’s power. However, it can also work with either DC or AC outlets, giving the VW driver more options.
Volkswagen hasn’t said anything about bringing the e-up! to the U.S. but, considering that VW doesn’t even sell the conventional up! here, it seems like a long shot.
Would you consider buying this mini VW EV with a maxi range? Tell us in the comments.

Cars

Driving design: How DesignNobis’ V-Tent could help EVs charge themselves

Whether you buy into the idea that alternative fuel sources are truly viable in the years to come, one thing is for sure: All that oil is going to run out someday, which is exactly why we must look to alternatives now. A number of car manufacturers are already hard at work solving this problem, but it’s going to take more than just automakers and legislation to drive us out of the oil age.
Enter Dr. Hakan Gürsu and the team over at DesignNobis. The small Turkish firm recently developed a rather clever EV charging concept called the V-Tent. While the V-Tent was designed to shield your vehicle from the Sun’s harmful rays, it doubles as a solar-energy gathering canopy for recharging an electric vehicle’s thirsty battery. We got in touch with Dr. Gürsu to get the lowdown on whether the V-Tent could solve some of our alternative fuel woes.
DT: The V-Tent is certainly a captivating concept. What was the inspiration behind its design?
The idea behind the V-Tent concept goes back to the many sunny summer days along the Mediterranean. Here, it’s hard to find a shade to park your car under, so we decided to develop a tent that protects the car, and produces energy at the same time.
What is the creative process behind developing such a concept?
Typically, the process starts with observation and then defining a problem. There were some criteria we wanted to follow for the V-Tent. For example, we wanted it to be collapsible, almost transparent in a way, when not in use. We decided that it needed to allow for both individual and public use. And it should be supporting technology and user interaction as well. Since we are focusing on ecological, energy saving products, we are keenly interested in solar energy. Our research team is following state of the art technologies and data, while our product development team focuses on design and engineering. There are also a number of different software used for production, animation, and simulation.

Even though the V-Tent is a concept, are there parts to it that are feasible now?
Feasibility of the V-Tent correlates to the EV market. In the U.S. and Europe electric cars are becoming widespread.
Could the technology be modified to be on-board, so EVs could drive with the tents "folded" up and then deployed anywhere when a charge was necessary and sun was available?
It may decrease aerodynamics, increase weight and costs. Our aim is to solve the problem more for public use and maximum efficiency with less initial investment.
What are some advantages of the V-Tent?
There are a number of advantages: Your car is safe and protected from environmental effects, and it’s getting charged at the same time. Also, public usage enables easy access since you can charge your car where you park it. Our concept system also has a simple interface with charging time information and payment options built in.
Are you in talks with any companies to develop a working model?
The V-Tent concept has been honored with the 2012 Green Dot Award, and we plan on entering new competitions, too. There are some offers we will be discussing; however, a low-tech version can be readily built with advertisement on textile instead of solar panels. That would also work as ad income for system installation.