Hydrogen Conversion
 

I've been poking around and have an idea.

My daily travel from home to work is around 13 miles. Round trip runs me almost exactly 26 miles each day, usually only a couple tenths under that.

Assuming this uses at most 1.5 gallons a day, how much of a storage system for hydrogen would I need to store and have that on a daily basis? Even if it involves changing out tanks.

I should be able to run some small compressors in series to get up around 600 psi if I need it. I had that for a cooling system that i had in high school that used argon for the refrigerant so it should work here.

I'm not sure if this website is credible, but here's what I found at https://www.mb-soft.com/public2/hydrogen.html This website is clearly anti-hydrogen.

"Consider a mid-sized car, traveling at 60 mph down an Interstate Highway. It is well known (and easy to calculate) that roughly 40 actual horsepower is needed to maintain a constant speed. A horsepower is equal to 2544 Btu/hr, so we are talking about 102,000 Btu/hr of "actual" energy/work. For an hour's driving, we would therefore need 102,000 Btu of output energy, to ACTUALLY MOVE THE CAR THROUGH THE AIR AND WITH TIRE RESISTANCE. (A gasoline engine would use maybe 3 gallons of gasoline during that hour's driving [20 miles/gallon] which actually contained about 378,000 Btu of energy, but the engine/car efficiency is only roughly 25% to create the 102,000 Btu of output work.)

Consider now that a cubic foot of Hydrogen (not compressed) only contains 319 Btu per cubic foot. That hour of driving would therefore require (102,000 / 319) over 3,000 cubic feet of the Hydrogen! Notice that this does NOT refer at all to any engine or drive system, and is instead simply considering the Aerodynamic Drag of the vehicle pushing its way through the air at 60 mph and the Tire Resistance Drag due to the tire sidewalls flexing each time the tires rotate. The ACTUAL efficiency of existing vehicles being around 21% means that IF Hydrogen was burned as fuel in a vehicle, we would need to duplicate that actual 378,000 Btu of source chemical energy, and we would therefore need to use up (378,000 / 319) around 1200 cubic feet of Hydrogen for that hour trip.

We can say this same thing in terms of "gallons". A gallon of gasoline contains around 6 pounds, and has 126,000 Btus of energy in it. A "gallon" of hydrogen (gas) only contains around 40 Btus in it. Quite a difference! Instead of a two cubic foot gasoline tank (15 gallons) in your car, you would need a tank more than 3,000 times bigger, over 6,000 cubic feet, for the equivalent Hydrogen! That's a little more than TWO standard semi trailers (8'wide x 8'high x 45' long or 2900 cubic feet each). Pretty big gas tank!"

Short answer= hydrogen has 36,000 BTU per gallon
propane has about 91,000 BTU per gallon
gasoline has about 115,000 BTU per gallon
so it would take 3.2 times the amount of hydrogen to go the same distance as you do on gasoline (assuming the same conversion efficiency).
So, if it takes 5 pounds of gasoline (1 gallon), it would take over 15 pounds of hydrogen to go the same distance.
How much water would you have to split to make 15 pounds of hydrogen?
Water is H2O and the atomic weight of oxygen is 16, each of the two hydrogens have a weight of 1, so hydrogen is 2/18 or 1/9 the weight of water.

So, you would have to electrolyze 135 pounds of water to get 15 pounds of hydrogen (the equivalent of 1 gallon of gasoline)- that's about 15 gallons of water.

According to the above article, it takes 21 KW to make one pound of hydrogen- so 21Kw x 15pounds= 315 kw x $0.08 cents per KW= $25.22 of electricity to make enough hydrogen to be equivalent to a $4 gallon of gasoline.

And so is that an 'anti-hydrogen' conclusion?

It seems that way- I've never had any feelings against hydrogen, but when I ran the numbers, it doesn't look very promising- unless we could use solar energy for the electrolysis.

It's just too bad my apartment complex doesn't have natural gas to the apartments themselves and that hydrogen can't be stored in liquid form.

Bummer!

Electrolysis of water is not 100% efficient. Electrolysis will consume more energy than will be recovered by burning the resultant hydrogen and oxygen. That burning will also not allow 100% recovery of the thermal energy and conversion to mechanical energy (motion) or electricity.

Very true- but if solar cells were available and you didn't have/want to spend money for the batteries/inverter for storage, you could just hook the solar cells up to a hydrolysis unit.

One simple approach to this perplexing question is to use a marine deep cycle battery recharged by a solar panel and completely remove the hydrogen generator from the vehicles electrical system then you can power the generator for free once you have seen the savings from the increased fuel economy. The deep cycle battery can run at 20 amps for very long time without drawing it down too far unless you are on a long trip then you can just stop at service station and have them recharge the battery on the quick time mode and be on your way in no time.

There are so many ways for this system to work independently from the vehicles electrical.

I ran some numbers a year ago on solar panels... for $7500 I could get enough panels to cover a 2004 Dodge Dakota. You could recharge a 45 amp/hour deep cycle battery in 10 days with that setup.