Comments on: 40 Hydraulic Hybrid Vehicles to UPS’ Fleet http://www.hybridcars.com/40-hydraulic-hybrid-vehicles-ups-fleet-53563/ Auto alternatives for the 21st century Mon, 03 Dec 2012 19:24:39 +0000 hourly 1 http://wordpress.org/?v=3.5.1 By: John K. http://www.hybridcars.com/40-hydraulic-hybrid-vehicles-ups-fleet-53563/#comment-40782 John K. Fri, 12 Oct 2012 15:34:25 +0000 http://127.0.0.1/wordpress12/?p=12694#comment-40782 This is good news. One of the main disadvantages of battery regen is the conversion from kinetic energy to electricity to chemical energy and back is, IIRC, only ~30% efficient whereas w/hydraulic hybrid or KERS (e.g., Flybrid), IIRC, it is about double that.

Second, unlike batteries, neither of those two mechanical hybrid systems’ energy storage units degrade w/time, temperature, or usage, which is critical in individual/commercial buyers’ cost-benefit calculations. Thus, mechanical regen might be ideal for HVs.

It could be that the best combo would be something like Flybrid for brake regen on a PHV, PHEV, or even a BEV. It would spare the main storage unit (batteries), from constant charging and discharging, allowing it to last longer before loss of capacity and needing replacement.

Last, does anyone know the approx. efficiency of conversion and back for ultracap regen? Do unltracaps degrade w/time, temperature, and/or usage?

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