The Poulsen Hybrid: A Follow-Up

There was a lot of excitement about the Poulsen Hybrid, and for good reason. It seems like a good, relatively cheap way to convert just about any vehicle into a mild hybrid.



For just a few thousand dollars, you can get better fuel economy by plugging your car in overnight. All of a sudden, you wouldn't have to wait several years and pay $40 thousand for a plug-in hybrid. If it works, you may not have to trade in your big car for nothing or wait six months and overpay for a Prius.



Projected Prices

• At this point the projected price of the basic kit is app.: $3,500


• Deep cycle lead acid batteries (not included): $400-450


• 72V 15 A charger for lead acid. (optional): $300


• Installation: $500-600


• 4.3 KWh Lithium Ion battery pack with battery management system and dedicated 25A charger: App. $4,500

But that's a little bit too optimistic and, truthfully, the system is still a few months away and there are still a lot of questions to be asked. Which is why I sent an e-mail off to the makers of the Poulsen Hybrid with some questions. They let me know they would be putting together a FAQ and I should check for it. Well it's up and there are some answers, but still some questions.



When Can I Get it?  Where?

The Poulsen Hybrid system will be available in the Fall of 2008, but you'll have to bring your car to Shelton, CT to have it done. Right now, they are the only ones who can do it, although they've seen a lot of interest from others who are very interested in doing it themselves or by dealerships who would like to be authorized to do the work.



The motor is attached to the wheels and the battery pack and controllers are placed in the trunk of the car. The motor adds about 2” each side at curb height and 3-4” inches at the center of the hubcap.



Any type of car with 15" wheels or larger can be converted, but not all models are built the same. The torque bar needs to be attached somewhere, and there is no one size fits all kit. Larger vehicles are not eligible, yet, but they hope to have something for SUVs and such by 2009. They are planning on concentrating on fuel efficient or popular cars at first. Trunk space is important, as well. The batteries and controllers take up a lot of space.



The DOT has not approved the system, yet. They don't expect there to be any issues with the DOT, but until they go through the process, it's anyone's guess.



The controllers are not connected to the accelerator pedal, but are controlled by potentiometers located in a pot box which is connected with the power supply in the trunk by a 10 ft, cable. A toggle switch serves to turn the system on and off.



They are working on some (optional) instrumentation to give the user readouts on mpg, remaining charge, instantaneous horsepower delivered by the ICE, etc.

The torque bar connects the motor stators with the vehicle body. The attachment hardware consists of a combined ball- and telescoping- joint, which compensates for possible misalignment during installation as well as relative movement as the car is traveling on the road. The connecting point may be forward or rearward of the wheel center, and in one form is a plate shaped after the fender contour and mounted by means of 6 self-threading screws. The relative forces are translatory, parallel to the body surface and directed downwards while driving and upwards during regenerative braking. (vice versa if the attachment point is forward of the wheel center). The choice: Rearward or forward of the axle depends on the vehicle architecture.



An alternate form of torque bar attachment includes a plate, which is mounted internally in the wheel well and protrudes close to the fender next to the wheel. The plate ends in a pinion, which connects with the ball joint. This form of attachment is suited for some car models and avoids drilling holes in the fender or elsewhere in the body.



The torque bar is a rectangular tubular aluminum extrusion and doubles as a conduit for the power and control cables leading from the power supply in the trunk to the motors. The cables exit the bar on the inside next to the ball joint and may be guided beneath the sub-fender, through a bore in the spare wheel well and on to the power supply components in the trunk area.



How Many Batteries? The standard batteries will be 6 standard deep cycle lead/acid 12V 100 Ah batteries connected in series. The system requires 72 volts, but the batteries are optional when the system is installed. They will also offer an optional 72V 15A lead/acid charger. A lithium-ion battery pack may be in the future.



Converting a Prius/Hybrid? 

They are going to convert a Prius with their system, although they feel it's redundant to do so. They will report on the results after their trial.



Bottom Line, What Kind of Difference Does it Make With the MPG?

They'll post third party performance reports on fuel economy when they start coming in.



How is the Battery Pack Recharged?  What About Regenerative Braking? 

Regeneration (braking) is engaged via a relay connected with the brake light circuit. A light touch of the brake pedal, without the pads actually contacting the drums or disks, will enable recovery of most of the kinetic energy. Practically zero energy will be recovered in an emergency brake situation.



Safety Concerns?

Some concerns have arisen over changing a tire. They estimate it will only take 10 minutes longer if you have a flat with the system.



Other Questions?

I've seen some question how easy it would be to steal such a system.  Since it only takes a few minutes to remove the motor, how easy would it be to steal one?



It's nice to see there will be a regenerative braking system, but that leaves the question of how long you can expect the system to run for (how many miles) before it needs to be plugged back in.  Also, what's the durability of the system?  How often will you need to replace the battery packs?  What if you wanted to remove the system?  Would you be left with any holes in your car? 



Still, all in all, this still seems like a very exciting system.  We'll have to see whether it makes a real difference in fuel economy or not (I'm looking forward to those third party reports).