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New age for old tech? Honda Civic Natural Gas tops Ford Focus Electric as 'Green Car

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A great fleet car, where the lack of natural gas fueling infrastructure won't be a problem.

Depending on criteria, Model S might not be the "Green Car of the Year." Some BEV econobox could be greener; something like the Coda could actually surpass Model S in CO2 saved. Model S should win MT CotY, though; it's not just the best green car, it'll be the best car of 2012.
 
I wrote up an analysis of cng cars on my blog.
They are inferior to EVs.
If you have a fleet and need to build infrastructure you are much better off building EV infrastructure.

Compressed Natural Gas | High Speed Charging
Read and let me know if you disagree.
You've convinced me. (I was surprised to learn, though, that there's a public CNG station less than a mile from my house.) Makes me wonder why a large chunk of the buses in Boston use CNG. Hopefully they shift over to EV as battery tech matures.
 
rich,

Thank you for your in-depth analysis. Again a big surprise that EVs beat any other propulsion with their efficiency!

Trying to help improve it:
You can buy a home CNG filling unit that will cost you about $6000 installed. It can refill your car in about 16 hours. But it uses 800watts to do that, so in 16 hours it would consume 12.8kW of electricity.
make that 12.8 kWh.

If you refill exclusively at home, you will spend $932 per year on fuel ( $857 on the CNG and $75 on the electricity to run the compressor! ).
Would be easier to understand if you state the miles per year and your home tariff for electricity and natural gas.

The Leaf is rated at 34kW per 100 miles, so $448 per year in electricity.
make that 34 kWh.
 
You've convinced me. (I was surprised to learn, though, that there's a public CNG station less than a mile from my house.) Makes me wonder why a large chunk of the buses in Boston use CNG. Hopefully they shift over to EV as battery tech matures.

In terms of cost per mile and emissions CNG vehicles are superior to gasoline vehicles and the technology has existed for a long time before EVs became viable.
They were a reasonable step before EVs became viable, but any new investment in them is investing in an inferior system.
 
I wrote up an analysis of cng cars on my blog.
They are inferior to EVs.
If you have a fleet and need to build infrastructure you are much better off building EV infrastructure.
Compressed Natural Gas | High Speed Charging
Read and let me know if you disagree.

Yeah, I recall previous analysis concluded the same thing. (Electricity needed to compress negates some of the benefit.)
By the way, although dated, it might be worth a little visit to this old thread:
CNG REEVs?
I still don't understand why we don't see diesel or CNG hybrids... Basically only gas.
Adding a hybrid drivetrain to a CNG car should increase its' range and efficiency just like it does for gasoline vehicles.
 
I still don't understand why we don't see diesel or CNG hybrids... Basically only gas.
Adding a hybrid drivetrain to a CNG car should increase its' range and efficiency just like it does for gasoline vehicles.
Perhaps it is too much to ask people go hybrid and then even use an alternative to conventional gasoline. Or car manufacturers think so.
 
....I still don't understand why we don't see diesel or CNG hybrids... Basically only gas.
Adding a hybrid drivetrain to a CNG car should increase its' range and efficiency just like it does for gasoline vehicles.

Diesels are expensive, hybrids are expensive, diesel-hybrids are expensive squared. Same goes for CNG or LNG hybrids, and with natural gas cheaper than gasoline or diesel, there is less motivation to conserve. I think this is why. For now, a cheap gasoline engine is the best economic match for a hybrid.

You are correct about the range and efficiency, of course. Diesel hybrids are available in commercial trucks and busses, where the default powertrain started with a diesel. We should see diesel hybrid cars in Europe someday. Peugeot has announced they plan to sell one.

GSP
 
Diesels are expensive, hybrids are expensive, diesel-hybrids are expensive squared.
But diesels are extremely efficient in a narrow rpm range so I would think they would be perfect for the type of hybrid where the engine is acting purely as a generator and not driving the wheels (like on a Prius). Stopping and starting a diesel and running it cold is very expensive efficiency-wise but once you get it running and warmed up it uses very little fuel.

My guess as to why we haven't seen any diesel hybrids is because everyone's (except maybe Fisker?) following the Prius model of having the engine drive the car so it's stopping and starting and varying rpms all the time.
 
I still don't understand why we don't see diesel or CNG hybrids... Basically only gas.
Adding a hybrid drivetrain to a CNG car should increase its' range and efficiency just like it does for gasoline vehicles.

That is by design to allow JET A to be available at a decent price for american air carriers and government uses. Jet A is basically the same product as diesel fuel. For every barrel of crude there is only so much product of each fraction, ie, diesel (Jet A), gas, and heavier products. The american market has been manuvered to using more gas, and ethanol to allow Jet A to go to Aviation and military uses.
 
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But diesels are extremely efficient in a narrow rpm range so I would think they would be perfect for the type of hybrid where the engine is acting purely as a generator and not driving the wheels (like on a Prius).

I think you mean "(like on a Volt or Fisker Karma)". You correctly described how the Prius "parallel" hybrid system works in your second paragraph. I also think the diesel would be good for a "series" hybrid power train.

In the end, anything with a fossil fuel burning engine in it is carrying around boat anchor technology. BEV is the future.

P.S. I figured out the other way to read your sentence so it makes sense the way you wrote it... Now I'm just too lazy to delete what I wrote and it might be nice to have it for clarity's sake for people who read it the wrong way the first time :wink:
 
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