The 'perfect' hybrid...CNG?

There are many benefits to using CNG or even propane. Otherwise fleet and commercial vehicles wouldn't bother with it. It's just that many of those benefits fade if they go mainstream and demand grows.

Cost will go up with spikes in winter when it competes with home heating.
It burns clean, but any damage from drilling will rise.
Foreign oil wells will stop burning NG off and collect it. Imports may not happen, but our demand increasing prices benefits those hostile parties.

That's far down the road, and based on the success of the GX not likely at this point. That also means the chance of somebody offering a hybrid CNG car for sale anytime soon will be slim to none. Conversion is still an option, and don't think here would poo poo the idea.

 

Just saw this on 60-minutes, sounds like it's working, NG-to-Elec fuel cell "Bloom Box", for household or large office space. No mention of cars though.

[ame="http://en.wikipedia.org/wiki/Bloom_Energy_Server"]Bloom Energy Server - Wikipedia, the free encyclopedia[/ame]

 

The 60 Minutes story can be seen/read at The Bloom Box: An Energy Breakthrough? - CBS News. I believe I saw it on TV when it was first aired.

 

It is too expensive and large for cars. At $7-8/watt and assuming it only had to generate 10kW (the lowest estimate I found for the power of MG1), it would cost $70,000. A residential Bloom Box is the size of a refrigerator, which may be able to generate up to 5kW, so it is way to big for a car. Bloom Boxes make sense for fixed installation in homes/businesses, where you can afford the space and amortize the cost over many years of continuous use.

 

Any thoughts on this?
Ford S-Max Hybrid Uses Advanced Capstone MicroTurbine Power | GreenCar.com

 

Nice prototype. I would love to hear the sound it makes.

Turbines are the best way to get kinectic energy from a fossil fuel. Also makes for roasting hot dogs out of the exhaust just before takeoff.

So using them as on-board generators to simply 'skip' charging from the plug makes sense in a variety of situations.

 

If using NG for electric that would be inefficient. The majority of available hydrogen today is made by stripping it from NG. There are home units that will already do this for a fuel cell vehicle. Going NG to electric to hydrogen will suffer more conversion losses. As always, if you have electric, you are better off with an EV over a fuelcell car.

 

I believe the microturbine was the hope of many for a plug-in series hybrid.

 

I'd like to see some mpg numbers on using a microturbine. The article states, "Whisper Eco-Logic can travel up to 40 miles on electric power alone and has demonstrated a top speed of up to 80 mpg in early testing." I think mpg is a typo for mph, leaving no metric for efficiency.

I like the idea, but on first blush, you have conversion to kinetic energy, then to electric, then back to kinectic, with conversion losses at each step. Thus, I'm a bit skeptical about its efficiency compared to systems that have fewer conversions.

 

didn't anyone here see the converted prius? it required a turbo.. did two seconds slower to 60.. and made a lot of noise...

sure.. it's cheaper.. but why try to build an entire market on a product that requires more energy than we currently put into it... just to get less out.

the cng civic sells well.. i see them all over los angeles... up in the san francisco bay area too.

i see cng as a sidestep to electricity. charging electric cars is expensive here in los angeles... our currenty kw price is 13 cents.. with a very small section of 15 cents, then it jumps to 20 cents... we currently tap the 15 cents per kw... at 20 (basically all the charging for the car puts it about on par to what the current prius gets).... cng requires more time than normal gasoline... like a plugin.. and requires certain stations to use... like a plugin...

 

That's an issue for any series hybrid, even freight trains. For a primarily EV PHV, the only other system is to integrate a parallel hybrid path like the Volt. Correction, there is also fuel cell vehicles.

Turbines are more thermal efficient than pistons, so it should do better fuel wise. They are more compact and lighter. Which might help with EV range, but will help with cargo and passenger space.

Series hybrids do have an advantage in opening up design possibilities. For example, by not having to be tied to the propellers drive train, ship engines can be placed where their mass is best supported by the hull and add stability. Realisticly, passenger cars likely won't take this advantage, and will be better served with some parallelism, but story can be different with buses and large trucks.

I haven't. CNG does contain less energy than gasoline per volume, so decrease in performance shouldn't surprising in a small engine. Most converted vehicles do have V8's or larger. Then aftermarket conversion kits are made for Otto cycles and diesels. I doubt there is any available with an Atkinsonized Otto in mind, and more development and tuning is needed to get it working right.

I'm sure the Civic GX is common in some areas, but it has been out for years and is still a limited market vehicle. I think I have to goto NY for one.

 

In the Volt's case, I believe there are losses b/c they use a clutch for the parallel path. Anyhow, my point is that with a turbine, I believe it cannot change the RPM as quickly as in an ICE. Thus, it would need a clutch or torque converter for a parallel path to drive the wheels and there are additional losses in those components.

I disagree; putting in wheel motors in a series hybrid gets rid of driveshafts/differentials, gives you all wheel drive, and probably increases regenerative braking efficiency, in addition to freeing up where you place components. Why wouldn't passenger cars eventually do this?

 

I thought about wheel motors, but didn't look that far down the line. Turbine plus them will be costly for now.

If the Volt didn't have a clutch, there would be losses in the EV and series hybrid mode. Any loses that might be there are tiny. A turbine might make the electric efficiently enough that it could beat a Volt like car in CS mode in economy.

 

I don't believe there is anything inherently expensive about wheel motors and that they are currently expensive due to low volume. Turbines, on the the other hand, require very high tolerances making them expensive. Perhaps a manufacturing breakthrough or volume production would help with that.

I disagree that the losses in series hybrid mode are tiny. The series hybrid functions more efficiently than an ICE at low speeds/RPMs, but at high speeds/RPMs an ICE driving the wheels is more efficient, which is why they put in a clutch/parallel path in the Volt in the first place.