What ever happened to HHV technology?

[Autobahnschleicher]

Originally Posted by Isaac Zachary

Does that mean there are a lot of electric hybrid or full BEV delivery trucks, trash trucks, metro buses and school buses now?

Or why did places like Orlando change their hybrid trash trucks in for CNG non-hybrid trucks?

At least here in germany the Deutsche Post/DHL actualy went so far that they started building their own electric transporters for delivery applications.

[Piotrsko]

There was a program on NOVA/PBS last night where the mentioned in passing that someone was making a hhv to electrons airplane. About 1 minute long with no real details.

[cRiPpLe_rOoStEr]

Originally Posted by Isaac Zachary

why did places like Orlando change their hybrid trash trucks in for CNG non-hybrid trucks?

Most of the people who know me believe I am unfavorable to CNG, but when it comes to garbage trucks resorting to biomethane which can be sourced from the landfills makes a lot of sense. And it's also easier to close the carbon and nitrogen cycles than resorting to an EV-only approach while either releasing raw landfill gas on the atmosphere or simply burning it away.

[JSH]

Originally Posted by Isaac Zachary

Or why did places like Orlando change their hybrid trash trucks in for CNG non-hybrid trucks?

CNG has become increasingly popular because fracking reduced the cost of natural gas and CNG trucks do not require diesel particulate filters or urea injection to meet emission standards.


The equipment required to meet emission standards are moving customers away from diesels. Not just for light duty vehicles but also in the medium duty class. There has also been a recent increase in gasoline school buses.

[Tahoe_Hybrid]

Originally Posted by Isaac Zachary

Very probable.



The hydraulic hybrid was never intended to be a means to store massive amounts of energy but to work exclusively as a traditional hybrid that helps save fuel through regenerative braking. It only makes (made) sense on stop and go vehicles. Vehicles that cruise down a highway wouldn't benefit much from the regenerative braking.

At the time there weren't any Li-ion hybrids or EV's. The only thing that came close were the NiMH hybrids, namely the 1st Gen Honda Insight and the 1st and 2nd gen Toyota Prius. The NiMH hybrids were said to get up to 20% or 25% regen efficiency and weighed more per unit of power.

By comparison, the hydraulic hybrid systems that had been developed and tested at that time were 70% to 80% efficient at regenerative braking and were light enough to be easily adapted to commercial vehicles that normally need all the weight savings they can get in order to haul their cargo. For an example, on a full sized bus the hydraulic hybrid system might mean you would lose one passenger in capacity. (This is why many have serious doubts about a Tesla or other company produced battery electric semi truck. The added weight of the batteries displaces the weight of the cargo that can be carried.)

Anywho, for hybrids at least maybe the lithium ion battery caught up to and surpassed the hydraulic accumulator in power to weight ratio or effiency (I've seen claims of Tesla regen being 85% or even 95% efficent although I have serioius doubts.) Even if li-ion batteries don't surpass it in those aspects, they definitely do in terms of energy density, making li-ion batteries better for certain applications.

For an example, anything plug-in (hybrid or pure EV) would benefit from a li-ion battery. Also when traveling over mountains a lithium EV or hybrid system would help soak up energy while regening down the pass. These are things that cannot be done in a hydraulic hybrid.

I think what attracts me to the hydraulic hybrid idea is that it isn't affected as much by cold weather. My NiMH hybrids suffer quite a bit during the winter, and I'm sure a lot has to do with battery temperature since I can warm up the engine and catalytic converter, keeping the heater off, and still drive around without the engine ever wanting to shut off. And in our Nissan Leaf the cold still took a huge toll on range even when trying to hypermile without turning on the heater.

the issue with lithium is it bad for the environment, creates waste and can catch fire... Zero waste option

[redpoint5]

I still want to know how that story ended with the guy on here who was contracting with trucking companies to throw every trick in the book at improving fleet fuel economy, including insisting that HHO delivered results.

[samwichse]

They started using these around me a while ago. The van that usually delivered to my work was one. The driver was a friendly guy (retired last year), and he liked the take off torque when he jumped back in and gunned it to the next stop.

https://www.nrel.gov/transportation/...aulic-van.html

Scroll down to publications, view the PDF, and you can see that it made a big difference in real world delivery cycles.

The vans around my area still engine off stop, but I don't know if they're conventional hybrids now or the hydraulics still in service. I haven't asked, and the new guys (they float them around the routes) frankly don't seem to give enough of a crap about delivering anything for me to bother to ask if they know any thing about their vans :-/.

[cRiPpLe_rOoStEr]

Originally Posted by JSH

CNG has become increasingly popular because fracking reduced the cost of natural gas and CNG trucks do not require diesel particulate filters or urea injection to meet emission standards.

I have already seen a handful of trucks fitted with dual-fuel CNG setups in Brazil. Odd enough, an Euro-3 truck with a sequential CNG port-injection is as clean as an Euro-5 counterpart running only on Diesel fuel (and the DEF if it doesn't resort to the EGR instead).

The equipment required to meet emission standards are moving customers away from diesels. Not just for light duty vehicles but also in the medium duty class.

Even though I am mostly favorable to Diesel engines, sometimes it does seem to make sense resorting to CNG or ethanol in order to decrease much of the troubles with newer aftertreatment systems.

There has also been a recent increase in gasoline school buses.

A comeback for spark-ignited engines on buses in my country is not so likely, but if it ever happens I would place a bet on either ethanol or CNG and biomethane. Dedicated school buses here are more common for rural routes, so eventually resorting to locally-produced biofuels could make sense.

[JSH]

Originally Posted by samwichse

They started using these around me a while ago. The van that usually delivered to my work was one. The driver was a friendly guy (retired last year), and he liked the take off torque when he jumped back in and gunned it to the next stop.

https://www.nrel.gov/transportation/...aulic-van.html

Scroll down to publications, view the PDF, and you can see that it made a big difference in real world delivery cycles.

The vans around my area still engine off stop, but I don't know if they're conventional hybrids now or the hydraulics still in service. I haven't asked, and the new guys (they float them around the routes) frankly don't seem to give enough of a crap about delivering anything for me to bother to ask if they know any thing about their vans :-/.

It is UPS policy to turn off the vehicle every time you stop. I drove a conventional diesel and turned it off every delivery. Per UPS policy:

Stop, shift to park, set park brake, turn off engine, fold in driver mirror, open rear door, retrieve package, close rear door, deliver package, scan package and record delivery location, return to vehicle, crank engine, release park brake, fold out mirror, shift to drive, go.

The driver is allocated 30 seconds to do all of that. Drivers do not have time to talk to customers. They are on a clock and everything is tracked.

[cRiPpLe_rOoStEr]

Originally Posted by JSH

The driver is allocated 30 seconds to do all of that. Drivers do not have time to talk to customers. They are on a clock and everything is tracked.

Either UPS applies a different policy in my country, or drivers get lots at some places while they do a delivery