Just to reiterate what Dog80 pointed out upthread:
Propane - also known as liquified petrolum gas (LPG) - is not the same thing as compressed natural gas (CNG).
I didn’t say it is impossible, just impractical. I remember seeing the schematics of a modified for CNG car (I believe it was a VW Passat) that also had a decent range. The car had two huge longitudally mounted gas cylinders running almost the whole length of the car. These were on the car’s floor.
Obviously it was redesigned from scratch. Retrofitting a car for CNG will be a lot harder and yield poor results.
As some others have pointed out, the tank has to go somewhere and it’s usually in the trunk of a car making it impractical to haul anything. It does appear to be practical to use for buses and trucks.
Somethings others haven’t mentioned is the fact that the mileage per gallon is less than a gallon of gasoline. Another thing is it burns dry, meaning that it has no lubrication and a bottle of some type of oil must be put under the hood to lubricate certain things that normally a gasoline fueled car wouldn’t have to worry about.
My father was a LP nut! There is no way of getting around some leakage and even a very small amount when filling the tank will linger with the smell of rotten eggs.
In the United States, it wouldn’t be practical to go cross country on such a set up unless those places that can fill this type of set up is mapped out a head a time. Also, it’s almost impossible to try to find someone to work on something like this.
I don’t think that is entirely true. If we run into a peak-oil scenario, the rest of the world will still be running on petroleum and there will be no hiding from the economic fallout. Here in the US we will have an ace in the hole is all, but it wouldn’t be so easy to just switch everything to NG.
I’m not down on NG, I’m just saying petroleum is still key to the global economy.
The tank isn’t THAT big. Every single Taxi in most cities in Australia is run on LPG. The trunk space is reduced, but it’s still there. Even the taxi’s that pick people up at Sydney airport are all run on LPG and they still manage to fit peoples luggage in.
Problems with NG vehicles:
Infrastructure exists less than the infrastructure for EVs. No filling up at home is not a reasonable option. Honda had sold “Phil” to fill up their NG vehicle at home but have stopped selling it.
Chronos made the cogent point that “It’s not practical to dedicate power plants to anything” and the same logic applies to powering our transportation infrastructure. Natural gas is in a boom right now but for how long, especially as more and more power plants switch to NG? The answer is that no one knows. Increase demand may cause big price spikes. There is plenty there to last for several decades at our current usage rate but how long will it last as we switch to more and more gas powered electricity plants, let alone to a sizable number of NG vehicles? Long enough that building a delivery infrastructure for transportation makes sense? Are we sure?
Using electricity OTOH allows flexibility. NG, nuclear, renewable, whichever ends up making the most sense for the time.
The limting factor for electricity right now is not the generation capacity. Previous analyses have shown that we ample surplus generation capacity available *at non-peak times *to charge a nearly complete transition to EVs today (and with real time pricing consumers can be amply motivated to charge at night); the issue is that if one block or neighborhood goes mostly people buying EVs who all want to rapid charge at the same (cheaper) time then the local transmission infrastructure may not be up to task. It argues some for distribution of generation. If NG stays cheap enough then residential fuel cells or combined heat and power cogeneration (micro-CHP) running off NG will makes sense. Even with tax credits they are currently too expensive but costs are expected to drop rapidly. (Or home wind power that provide some of that power at night when the electricity produced would otherwise be of little need.) The idea pertinent to this thread is that having NG power vehicles is wise for now while we have plenty but the means to do it is to have that NG competing with other sources to produce electricity which proximately powers the vehicles to degree it is possible. Then as even cleaner and cheaper electricity sources emerge the transportation infrastructure indirectly switches as well.
My company is deep into the process of building a liquefied natural gas (LNG) production plant to provide LNG for transport. LNG has a higher energy density than CNG so range is increased over CNG. However, it’s still less than petroleum and there would be very few places to fill up. Therefore, our target market are short haul trucks that return to base every day. We’ll provide a few few vessels scattered around a large operating area and then have refueling trucks swing by every few days.
There’s a lot of potential demand for LNG fuel in high horsepower applications such as ferries, buses, short haul trucks and oilfield equipment such as frack pumpers and oil rigs.
Replacing diesel with LNG yields about 20-30% fewer GHGs, 70-90% less CO and 90% fewer particulates.
Finally, there is very little data on methane leaks on the natural gas industry and so it’s probably too early to call those estimates ‘science’ and even if the leaks are what NCAR estimates, there’s big money to be saved in finding and eliminating those leaks so I think the leak numbers will climb downward very quickly. The leaks are not a fundamental part of the the emissions profile, they’re just not economic yet. I’m comforatable in believing a very clean fuel will become evern cleaner over time. That said, readers must understand my bias as somebody who has a commercial interest in greater use of natural gas as a fuel.
The Phill was crap. I’m surprised they sold as many as they did. There is plenty of activity to make a product available that is not crap. However, you are limited to about 2 scfm on a typical home NG supply, which comes out to about 1 GGE/h. That will fill you up overnight.
I got to see a driveaway at a fast-fill CNG station this summer; a CNG taxi driver forgot the hose was still attached. Whoops! Whatever safety equipment they have worked just fine though, as neither the taxi nor the pump vented more than an initial poof.
phreesh, I’ve also heard some talk of LNG trains (as in locomotive, not as in production facility); it seems that bigger is better for LNG applications.
Yeah. Actually, my firm (not mentioned) is part of the CN trial in the article linked upthread.
Apparently reading is hard. I completely skipped over gotpasswords’ post.
Your statement is generating a syntax error … I could not get it to compile cleanly!!!
