DIY flex fuel, hydrogen, natural gas, ???

[skewbe]

I'm going to be optimistic and put this in the DIY section

Scenario: You have natural gas pumped to your house, or an abundance of electricity from your ingenious solar panels/windmills/spare nerve endings for electrolysis, or you have methane from your local landfill/pig farm, whatever. You want to get off of oil specifically and be able to go 50 miles round trip most every day on gaseous fuels.

Approach: For fuel injected cars (my favorite kind), you have a lot of what you need in place already. What is needed is basically a tank, a regulator, and a circuit to intercept the fuel injector signal and control a valve based on the duty cycle being sent to the now disconnected inector. This valve will control the flow of the gaseous fuel into the manifold near the throttle body.

Some assumptions:
1. The standard o2 sensor won't care, if there is extra oxygen then it is lean.
2. Let us say the car gets 50mpg. So we need 124000 Btu of fuel.
3. Want it to be low pressure, just enough so the tank isn't huge but a lot of energy isn't wasted packing the fuel in there each night.
4. easy to use
5. switchable between gas and gas
6. fuel maps in the pcm will magically work out to be ok once the system is calibrated (fingers crossed on this one)
7. This is going to take awhile to get to a working model.

[SVOboy]

What about propane?

[skewbe]

It can often be metered as a liquid due to distribution practices, but sure it will work here as a gas.

[SVOboy]

Well, the first generation of the NG civic GX was just the HX with a different tank and intake manifold/computer. I actually know a guy with the intake (unless he threw it out).

So I'd say it could be done. For the effort I would go ev though.

[skewbe]

I should have clarified, this is another ultracheap approach.

I'm thinking a regulator and tank(s) off a discarded bar-b-q and a circuit and a servo and a valve.

[SVOboy]

Aha! So how would you bypass the standard injectors?

[skewbe]

I'm just worrying about one injector right now (tbi), though it could be adapted to mpfi surely.

Ignoring the switchable assumption to keep things simple, you would unplug the injector so it is stuck closed, and plug into this circuit. The circuit would look at the duty cycle being requested by the pcm and open or close the valve accordingly.

[SVOboy]

Interesting. As long as you can get the injector switch to hook up to something that delivers a reasonably similar charge you should be fine. I was thinking you were planning on adding something vacuum based to just draw some amount of fuel and ignor the injector.

[skewbe]

Any guesses on how many psi I need to hold 124000 btu of ng in a couple BBQ tanks?

[skewbe]

Not sure this is in scope, but I get the feeling that 124000 btu of ng is going to be fairly large without a lot of pressuure.

"Using corncob waste as a starting material, researchers have created carbon briquettes with complex nanopores capable of storing natural gas at an unprecedented density of 180 times their own volume and at one seventh the pressure of conventional natural gas tanks."
http://www.solutions-site.org/artman...icle_318.shtml