Author Options:

electric ultralight cri cri (mc-15) Answered

i know ultra lights nomaly use gas , but i was thinking in one total eletric .
why? cuz its green , easier to make , easier to control, easier to repair  , and several others things. but it have a problem(of course it have a problem why air companys dont use eletric planes) .
so i get to the conclusion it have to be light (that means small to), and the electric motor would have to be efficient. so i think what plane i use ...... the aswer is the mc-15 or cri cri if u like that name is light allready have a eletric version(a crap flights for15 minutes only , but faster than the gas one) .(UPDATE)
ok to power the motors 4 of 24 volts i was thinking in a fuel cell aka hho cell. how i make thata fuel cell i already see instructables but it have to make 24 volts and turn upside down . im searching 4 a good fuel cell blueprint.(UPDATE)


The biggest problem with electric vehicles in general is where you get your energy from. Batteries have a very low energy density (amount of energy per unit weight or volume) compared to chemicals (such as gasoline). A popular solution is to use fuel cells where a chemical reacts with oxygen in a very controlled situation which generates little heat and much usable energy. Now you have the problem of what kind of fuel to put in your fuel cell. Hydrogen is popular but very difficult to store requiring a very heavy housing, this is why I like methanol instead. Methanol fuel cells are a bit more expensive than hydrogen fuel cells but considering the saved weight in the fuel storage they are well worth the trouble. Methanol is also easier to get as it is used in several industries as well as a auto racing fuel.
I think it is the french army that has equipped their soldiers with methanol fuel cell laptops which run for 72 straight hours on one cartridge as opposed to the 2-4 hours of Lithium ion batteries...

I am not sure if your magnetic motor idea is feasible. Sounds to me like you put in power to run a generator but perhaps I misunderstood.

The contra rotating props on a XF-11 improve the stability of the engine (by having the two props cancel each other's gyroscopic effects) and the efficiency (the first prop receives the air straight on and it leaves at an angle, the second prop receives this air at almost 90º angle because it is curved in the opposite direction). The downside of course is the mechanical complexity from having to axles spinning in opposite directions.

ok changed to fuel cell(man they r not so hard to make)

Have you come up with some magical method of efficiently and affordably refining hydrogen, and packaging it so that you can safely carry enough in an airplane to run for more than "a crap flights for15 minutes only"?

If you have, file a patent, you're practically a billionaire already.

hydrogen is taked of the water easily (if doesnt know the process search on google) i was thinking in puting on paintball air tanks(3500 psi) i some of the may actuly be carried at the wings. the fuel cell at behind and more 1 maybe 2 tanks at the front.

If you put two electrodes in water and run electricity through them, you'll have pure oxygen bubbling off one electrode, and pure hydrogen bubbling off the other. It's a fun little demonstration; I've done it myself with a 9V battery. However, that just gives you some bubbles of hydrogen. Yee-ha. What are you going to do with them?

So your paintball air tank can handle 3500psi. How are you going to compress the hydrogen to such incredibly high pressure, without letting air in (reduces capacity) and without letting hydrogen out (BOOM)?

As far as efficiency, as I mentioned below, the amount of electricity your fuel cell generates from a given amount of hydrogen is going to be vastly less than the amount of electricity you use to electrolytically separate the water, the electricity you use to compress it (however you do that), etc. Charging up some lithium batteries will get you a lot farther.

i agree the bubler will have to be strong anuff to (3500psi) compress anoff hydrogen to the air tank , i dont think its so hard to do it(dangeraus yes but not hard) .
fuel cell tech is far advanced from lithium batteries

Magic tends to be a rather unreliable method to use on an industrial level and it is traditionally difficult to patent.

Generating hydrogen is not a specially efficient or cheap process in any method (electrolysis, syn-gas, reformers, etc) but when using waste energy (like from excess supply from wind farms) it can be a very ecofriendly way to carry energy. Transporting hydrogen in sufficient amounts with minimal loss is best solved with hydrogen carriers in my opinion. These, and all related technologies, are most likely already patented every which way.

If hydrogen cars and buses have been made then for an airplane it shouldn't be too different, but I would strongly give preference to methanol which can be created (relatively) cheaply and stored safely and easily enough (which have both also been sufficiently patented).

As an alternative hydrogen carrier there is also ammonia which can be generated from waste energy (which is nearly for free). Ammonia (like methanol) can run direct fuel cells, be converted back to hydrogen for traditional fuel cells and be burned in combustion motors with minimal modification. (guess what, patents all round!)

-Generating hydrogen is a tremendously inefficient process. In the end, even with the most efficient methods available, three times as much energy is put into extracting/refining/processing the hydrogen as the vehicle it powers will ever receive. [citation needed] but I'm feeling a bit lazy. Suffice it to say that hydrogen is not a source of energy, but rather a medium of energy storage, and not a terribly efficient one at that.

-"Waste energy"? The only way to have "waste energy" in a wind farm is if the wind is spinning faster than the turbines can handle. If you have "waste energy" somewhere it would be put to far better use being pumped back into the grid instead of turning water into bubbles.

-Ever notice the range of all of the hydrogen cars and buses? It's amazingly short, often below that of a comparable electric. No one has come up with a method of carrying hydrogen (gaseous, liquid, or locked in a "carrier") that can safely hold enough to get you anywhere.

-Burning hydrogen in an ICE just adds more waste to the process. ICEs are ridiculously inefficient. Perhaps if you used a high-dollar Stirling, but a fuel cell will almost always get more (a third, remember) of the energy out of hydrogen then burning the stuff will.

-Doesn't Apple patent magic on a regular basis?

And now I've probably started a flamewar that I never wanted to get into because I can't keep my trap shut. There's a tremendous amount of misinformation out there regarding hydrogen, much of it apparently spewed by automakers demanding subsidies and grants to make their little toys.

Fair enough, to prevent a flame war I won't keep it going either.

I'll just clarify the "waste energy" bit for those interested in the technology involved:
Wind farms are capable of producing energy in a way that is unaffected by the demand. It is possible (and even common) that wind turbines generate an excess amount of power that the local grid cannot use (therefore "waste energy"). Several methods exist to store the energy during these peaks so they can be used when there is a high demand and low production. One such method is to use this surplus of energy (usually either free or very cheap) to purify and electrolyse water (for hydrogen) and to generate nitrogen (from air) which are combined into ammonia. This process is rather inefficient to store power but one of the few ways to create a liquid fuel from excess electricity (ammonia can be used in almost unmodified diesel engines).

I would suggest a metanol fuel cell rather than a hydrogen fuel cell. You could buy a completed product but if you want to build one yourself you have to buy the membrane (you cannot make this yourself without a very advanced installation). Beyond the membrane it is a very simple process to build the fuel cell (but a bought unit will probably be more efficient).

Good luck!

Not off the top of my head. Google is your friend ;)

oh !! , and i think carbon paper works like a pem

Something like this should do the job?
But I don't see any advantage over just running an engine on methanol...


great idea except with batteries that would be light enough to take into the air you would not get very long flight times as a matter of fact you might taxi off and run out of battery right after the ascent. Then you would also have to get it faa certified.

http://search.eaa.org/search?q=electric+flight&client=AirVenture&proxystylesheet=AirVenture&output=xml_no_dtd A lot of info on what's being done right now.

As lemonie stated, batteries are heavy. Airplanes have to be light to fly. With advanced aerodynamics, advanced batteries, and advanced materials electric airplanes are now approaching practicality, but only in prototype form, and not with materials or facilities you'll find at Home Depot.

And whatever you're trying to say about a "magnetic motor" (redundant, since all electric motors involve magnetism) sounds like BS.

The problem is with energy-density.
Petroleum fuel contains over 40MJ per Kg, which if you convert to Wh per Kg is over 10,000.
Batteries don't usually get much above 100 Wh/Kg, so you'd be carrying maybe 100x the weight in "fuel".

The bit about a magnetic motor(than u think ,wtf is that) the aswer is is like a eletric motor but maid with magnets thats spin a electric motor who generate energy powering batteryes who power tha engines sounds like one of those crackpot free-energy ideas...