AHANW Library
General Hydrogen Production and Conversion Information
Author: Abe Fouhy
Date: Jan 19, 2010
Here are some ways to create hydrogen that are economical in some small or large scales;
Well for starters you can get hydrogen from, water through electrolysis (water + electricity --> h2 + 02), and other sources such as biomass (organic material, such as garbage, sewage, agricultural wastes), petrol and plastics. So to start off you can make hydrogen from water economical with two factors 1) renewable power that pays the investment (money making hydrogen for your home or business by lowering the cost of electricity in them) 2) having an abundant supply of water. Now this is starting to become more practical through the use of powerful wind turbines, water turbines and higher efficient solar panels, respectively.
BUT you are correct that although this is an EASY way, it isn?t the most economical yet. Some other ways are through the use of Biomass. One way would be to take a biomass and put it in a vacuum and heat it to 600 degrees C, and extract the hydrogen through what is called Pyrolysis. You can either derive the heat from solar radiation (sun) or through electricity (like a giant toaster). You can also take bacteria and algae that will make hydrogen directly in the right conditions (controlled conditions of the hydrogen plant). Or you can pulsate electricity though the biomass material to secrete the hydrogen that way. This is just to name a few, so there are ways.. the biggest thing is trying to factor all the proven ways (many out there) to find what direction you want your "hydrogen maker" to go (what process).
Conversion of an ICE (internal Combustion Engine) to hydrogen
To convert an engine to run on hydrogen you need to take some things into consideration. Range, efficiency of the engine, if you want it to be dedicated hydrogen, and storage of the hydrogen.
First off lets start with storage, there are 4 stages of hydrogen storage and the 3 main ways are: Gaseous, Liquid, and Solid (hydrides).
Gaseous hydrogen is stored in either low-pressure 0-150 psi or high-pressure 2000-10,000 psi). You can store low pressure in a balloon, a rubber bladder, and propane tanks or in underground storage cavities for examples. For High pressure you will need to store these in tanks, steel (1000-2500 psi) or in carbon fiber tanks (1000-10,000, although they can easily store up to 40,000 and have a tinsel strength of 400,000 as of 1992. These tanks need to be regulated down to a useable pressure using hydrogen 2 stage or 2 single stage regulators (described further below). To calculate the volume of hydrogen in a gaseous tank you will need to use this formula (take the liters of the tank multiply it by .03531466 to get the cu. ft in a tank. Take the cu. ft and multiply it by 317 (BTUS in a cu. ft of hydrogen) and multiply it by bar then divide by 122060 (BTU's in a gasoline gallon equivalent). Example 50 liters x .03531466 = 1.7657 cu ft. x 317 = 559.737 x bar (680.272 bar @ 10,000 psi) (California?s legal limit) = 380773.408 BTU's in the volume of our tank / 122060 = 3.2 GGE (gasoline gallon equivalent). Most tanks are at least 97 liters.
Liquid- Liquid is normally 2.3 times the density of gaseous and is stored at -423 F. It is a good way to store hydrogen for quick use, because it will burn off 1-3% a day depending on the insulation. How this works is they have liquid nitrogen cycling through a 1 of 3 layers in the storage device to cool the hydrogen in the main container. For more information on this please go to www.ahanw.org
Solid- Solid can be stored many ways. Usually it is some form of a hydride, which is nothing more than a material that can hold hydrogen when heated up then cooled down. Most people these days are storing hydrogen in a metal hydride composing on titanium, iron, nickel, and rare metals. These can store anywhere from 2-3.5 times that of gaseous storage. For more information on metal hydrides see either www.ahanw.org or http://www.ergenics.com. There are many other sources to store hydrogen also as hydrides on example is solid carbon, with solid carbon you can hold at least 3/4 that the density of gasoline with further research should be able to have 3 times or more that of gasoline! You can get solid carbon from Pyrolysis stated above. There are also many nano carbon storage and some experimental subjects like microspheres and such.
To convert an engine to run on hydrogen AND gasoline, you will need to have your storage device securely fitted in the back with u brackets. Then you have your first stage regulator from your tank (most tanks have a internal shutoff and evacuation valve built in), then you have a check valve and flame arrestor and then a couple vibration loops and 1 more of each check valve and flame arrestor (all these are actually redundant) run all this with high pressure stainless steel lines to your second stage regulator which takes the pressure from 200 down to 100 or 50 psi to your fueling system. There are many ways to deliver the fuel to the engine, 1) a pre-existing natural gas system and then you get specs on converting the computer so that the injector timing is reduced 2) port injection where you take 1/4 stainless lines through the intake manifold to right behind the intake valves, for better efficiency you will have an Impco fuel injector on each tubing to each cylinder or equivalent 3) gaseous carburetor using a Impco, Mogas or other gaseous carburetor hook it on the intake manifold and 4) direct injection using stratified charge in the spark plug hole combining a spark plug and gaseous injector for ease. 5) Nitrous fogger kits, using kits to convert over the intake manifold, bolt up and configure!
Tuning your hydrogen engine - you can decrease the timing to near top dead center (hydrogen burns quicker so it doesn't need the same position), increasing or decreasing pressure to the intake, change the fuel/air ratio.
What you get will be a engine with 10-15% more HP, 20-30% more fuel efficiency (since hydrogen has 3 times the energy by weight of that of gasoline and 2 of that of propane) and 3-4 times the engine life of a gasoline or diesel (no carbon deposits) and you will have an engine that will clean the pollution (hydrocarbons) out of the air as you drive! Or generate electricity.
For information or questions on this or "how to convert to a fuel cell or hybrid (internal combustion and electric) please visit www.ahanw.org and join us on the forums!
I hope this helps you in your pursuit for hydrogen.
Sincerely,
Abe Fouhy