Converting Prius to Natural Gas

[ryogajyc]

I was wondering if anyone had considered this or knows what is involved in doing this. In my cursory examination off the first webpage from a google, it seemed like this could be done with the ability to switch back to gas as backup.

I'm partially interested in this out of sheer curiosity, but the other potential advantage is that it would allow the Prius to be CA carpool lane immediately as opposed to when/if the Senate passes the transportation bill.

BTW, the webpage I glanced at is: http://www.ngvontario.com/own_options.html

[lgeisz]

In my opinion there is a shortcoming to using CNG fuels the weight. I have used CNG vehicles for work in the past and the weight of the fuel tank and fuel could negate the benefits. Also the availability of CNG stations.

[ryogajyc]

From a benefit perspective, I'm mostly concerned with the following:
1) classification of CNG as a clean fuel
2) lower cost per mile than gasoline
3) cleaner emissions than gasoline

I am unclear whether gasoline or CNG has a better mileage to weight or volume ratio, or perhaps more appropriately termed usable energy per unit. You seem to indicate that CNG is worse in this regard.

However, I would want to use this as a clean, cheaper alternative for city commuting where the range mostly will be within 100-200 miles (or even less) with some sort of home fueling station (like the one leased for use with the Honda Civic GX). The ability to switch to gas as backup is a convenient solution to both range and CNG station availablity when wandering farther from home.

Keep in mind this is mostly a hypothetical exercise. I don't really have the money and time to truly look into this (unless it's a lot easier and lot less expensive than I think it is). It probably behooves me personally to wait and just see how the transportation bill goes. I am very curious on if other people have thought about this and what they've concluded, however. Thanks for you thoughts, lgeisz.

[DaveinOlyWA]

i have talked to a lot of people who drove CNG vehicles (mostly small pickups) and none were very impressed with the range, power or ecological aspects of the vehicles they used.

a few people did feel that they were great in providing niche services that involved stop and go low speed applications. one person (a known fanatical "greenie" who borders on eco-terrorism...well as much as one can who is doesnt weigh more than 90 lbs) who constantly derides the government for not converting all mail trucks to CNG.

one thing you might want to look at is cost. the trucks i mentioned are not used as much because the rise in fuel costs forced a move to a mis-mash of vehicles that include focuses, some Prius classics, Echos, etc. (iow, whatever was on sale that day and since this is not a state fleet, they have more leeway in what they can purchase to use)

[jayman]

The URL provided at top is for a Province of Ontario program to encourage greater use of NGV in the Greater Toronto Area. I'm not sure how this relates to the State of CA and carpool access for single occupancy.

CNG and propane conversions were popular here in the early to mid 80's when NG and propane were a *lot* cheaper. Also, it's much easier to modify a carburettor equipped vehicle to run on a gaseous fuel than to modify an EFI motor.

Both CNG and propane offer a lot of advantages for reduced maintenance as the motor usually stays squeaky-clean. However, you should run a special motor oil just meant for CNG and propane vehicles.

Most of the forklift's I've seen in warehouses run propane due to indoor air quality issues. I can't even imagine a diesel powered forklift run in an enclosed space.

Used in automotive applications, both propane and CNG have serious distance limitations. And in extreme cold (-15 F or colder) the regulator can ice up and you're not going anywhere. Most regulators and vaporizors have engine coolant piped through them to ensure the motor starts and stays running.

Some CNG users have switched to propane due to having fleet trucks stranded somewhere after running out. Propane is usually much easier to find to refuel.

[ryogajyc]

Well, the current CA limitations prohibit any vehicle which uses gasoline from it's clean fuel vehicle definition. I was thinking that converting the vehicle to CNG (a "clean fuel") would work-around this problem, but I guess I jumped the logical gun a bit since using gas as a backup would still disqualify a CNG converted Prius. Converting a Prius to only use CNG would leave it lacking in power, range, and limit its refueling locations. I guess that concludes any interest I have, real or hypothetical, in converting a Prius to natural gas.