I spoke to a lady with a CNG Civic last week

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EatenByLimestone

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She didn't like it. And it was a surprising reason.

She thought it was plenty peppy. It drove well. It was reliable. She didn't like that she was getting only 90 miles per tank.

The lady was driving a state vehicle in a mountainous area. I'm pretty sure she wasn't babying it. She said it wasn't too bad only going to the local DOT to fill up, but it was a pain that she only got 90 miles per tank. I was under the impression it would go a bit longer per tank of fuel. Maybe she was really hopping on it.

Matt
 
I thought they got around 200 per tank?
 
Depending on pressure CNG is about 1/4th as delicious as gasoline. I'm not in favor of running cars/light trucks on it by putting it in a combustion engine that's still only 17-25% efficient. Use it for a pony motor to charge a plug-in hybrid so you can cut down on the battery size/weight, but honestly we've already got the gas infrastructure in place so I don't think it's worth it (as long as we can get crude!). Gas is cheap if your first 40-50 miles comes from battery. Most people wouldn't have to buy it.

LNG is better but you have to get to -250F and that takes a ton of energy too. Maybe for trucks OTR.
 
CNG is appropriate for emissions reduction with current technology in densely populated urban areas. New Dehli mandated that all the tuk-tuk's (3 wheel taxis) be switched from kerosene or diesel to CNG a bit over a decade ago. It made a big difference there.

Mountainous driving will use more fuel. I'm wondering why she was so far afield in a state car.
 
I used to have one for work. My best ever was 275 miles per tank. It worked the best when you filled it up in the morning when it was cold, then as the temperature outside increase the tank seemed to never go empty. Many times though I could only go about 140 miles per tank. The car was pretty peppy just as peppy as a gasoline 4 cylinder. However I had to have it towed one time because the local CNG station went down.
 
Methane is 25x as bad as co2 to (I've heard). There's no reason to completely abandon gasoline for another dead end. I'd be changing my tune if I had ng at my house but I haven't startedpricing out explosion proof compressors yet.
 
Methane is 25x as bad as co2 to (I've heard). There's no reason to completely abandon gasoline for another dead end. I'd be changing my tune if I had ng at my house but I haven't startedpricing out explosion proof compressors yet.

Hi,
Its only 25 times as bad if its released directly into the air -- if its burned, it just makes CO2, and I believe it makes a bit less CO2 per unit of energy output than gasoline.

Gary
 
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When we drill, pump, pipeline, dispense and fill up we will have methane escape. Just moving it around will cause losses at every hand off, not to mention engery loss. It's better controlled at a single power station and then distributed through the electrical grid rather than a million (or a hundred million cars) more chances given to escape. Its much easier/cheaper to regulate at the industrial level than at the consumer level, and if you use it in an electric car you get 2.5x the mileage from the same amount of gas.
 
The addition of a CNG system to pickup trucks working the Texas oilfields used to be common. I'm not sure why it was but it was probably for the extended range as they maintained the function of the gas tanks.
 
When we drill, pump, pipeline, dispense and fill up we will have methane escape. Just moving it around will cause losses at every hand off, not to mention engery loss. It's better controlled at a single power station and then distributed through the electrical grid rather than a million (or a hundred million cars) more chances given to escape. Its much easier/cheaper to regulate at the industrial level than at the consumer level, and if you use it in an electric car you get 2.5x the mileage from the same amount of gas.

Hi,
Certainly agree that there are more opportunities for leakage if you use the cng for car fuel, but (I guess) there might be pretty good controls on that. We pipe ng to millions of homes without wholesale leakage -- until one of the old pipe lines breaks :)

I don't think that when you look at the whole process that making electricity with a cng powered generating station at 50% efficiency and then losing 10% of that on in transmission losses on the grid and then powering an 80% efficient electric powertrain in the car is going to end up being all that more efficient than a 25%? efficient cng car?

Gary
 
Modern gas engines max out about 30% efficiency, and that's without idling using the breaks or traffic. Gas fired cogeneration plants get about 60%. Even with transmission loses an electric car is always going to come out ahead eff wise.
 
You cant ague the cost per mile of electric or CNG at $1 a gallon equiv. It just the startup cost to get there.
 
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