# How do we make hydrogen? **URL:** \ **Category:** Factual Questions\ **Created:** [October 20, 2004, 4:03pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235 "2004-10-20T16:03:58Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![jebert](https://avatars.discourse-cdn.com/v4/letter/j/ec9cab/32.png) [@jebert](https://boards.straightdope.com/u/jebert)\ **Post date:** [October 20, 2004, 4:03pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/1 "2004-10-20T16:03:58Z")
Bush, among others, says the hydrogen economy is our way out of dependence on oil. However, a friend of mine claims that the manufacture of hydrogen requires natural gas as a feedstock, and that that renders the whole hydrogen effort a pipe dream. I’m not conversant enough with hydrogen technology to know whether or not natural gas is required, so I appeal to any doper who knows the process. If NG is required, is there nevertheless a net energy gain? Even so, would the finite supply of NG eventually mean we’d still have to go to something else beyond hydrogen? ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [October 20, 2004, 4:12pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/2 "2004-10-20T16:12:48Z")
Hydrogen is typically generated via dissociation of water using electrolysis. For hydrogen generated in this fashion, there can never be a net energy gain, since the energy released by burning it is exactly the same as the engery required to obtain it, and that’s assuming 100% efficiency. The electricity for the electrolysis has to come from somewhere, and that is usually coal and sometimes nuclear power plants. Either source has it’s own environmental issues, so hydrogen fuel can’t really be considered to be truly “clean”. Hydrogen can be generated in other ways too, and some promising methods using, for example, the waste heat from nuclear reactors, are being developed but for now the dream of a hydrogen fuel economy seems pretty far off. ---
**Author:** ![bouv](https://avatars.discourse-cdn.com/v4/letter/b/bc8723/32.png) [@bouv](https://boards.straightdope.com/u/bouv)\ **Post date:** [October 20, 2004, 4:16pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/3 "2004-10-20T16:16:26Z")
You need some way to generate electricity to seperate the hydrogen from oxygen in water. Which leads em to think: If we made a fuel cell car, would it run on water? That is, could you pump water into your tank and convert it to hydrogen as you burn it? If you put an alternator on the engine would you be able to make enough electricity to seperate the hydrogen AND still have a strong enough engine to move a car? ---
**Author:** ![gazpacho](https://avatars.discourse-cdn.com/v4/letter/g/6f9a4e/32.png) [@gazpacho](https://boards.straightdope.com/u/gazpacho)\ **Post date:** [October 20, 2004, 4:19pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/4 "2004-10-20T16:19:57Z")
Hydrogen is not generated typically with electrolysis. It is most cheaply generated with a steam reformation process. This is basically turning H2O and Carbon in coal into C02 and H2. ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [October 20, 2004, 4:20pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/5 "2004-10-20T16:20:49Z")
> [@bouv](#): > > That is, could you pump water into your tank and convert it to hydrogen as you burn it? No. See above. ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [October 20, 2004, 4:26pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/6 "2004-10-20T16:26:08Z")
Steam is typically used with natural gas via [steam reforming](http://www.fe.doe.gov/programs/fuels/hydrogen/hydrogen-from-gas.html). So yes, if we use hydrocarbons as hydrogen sources then we will run out of the stuff sooner or later. The emissions from the cars, however, will simply be water vapour. If you’re concerned about climate change/forcing then that’s almost obviously a good thing. People, being people will likely then begin to complain about increased cloud cover or something though. 🙂 Ultimately hydrogen is not an energy source it’s an energy holder. You use a primary energy source such as hydrocarbons, solar, fission, or fusion to generate power and then you store it, at a loss, within the hydrogen you create. ---
**Author:** ![Polycarp](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Polycarp](https://boards.straightdope.com/u/Polycarp)\ **Post date:** [October 20, 2004, 4:35pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/7 "2004-10-20T16:35:55Z")
Hydrogen is, of course, first and foremost an **element** , so it’s not “made” in the sense that other fuels are. As an element, though, it exists in compounds, one of which is “elemental hydrogen” – two hydrogen atoms joined to form a molecule. It’s the production of this from other compounds containing hydrogen as a constituent which “making hydrogen” refers to. As **Q.E.D.** points out, producing hydrogen from other compounds is (nearly always) energy-consuming rather than producing. (There are a few rather rare exceptions to that rule, which we can disregard for this discussion.) However, the idea of portability is worth taking into account. There’s an old joke about a car dealer selling an electric car for $100 – and then charging $5,000 for a thousand miles of extension cord! – that’s worth picking up on here. There are many means of generating or harnessing energy that are extremely localized – tidal, geothermal, hydroelectric, etc. Normally what is done to get the energy from the point of generation to the point of consumption is transmission as electricity across high-voltage power lines. But it would be quite easy to take water from Lake Mead, Grand Coulee Reservoir, Passamoquoddy Bay, etc., and electrolyze it with the power generated at Boulder or Grand Coulee Dam, the proposed Fundy tidal power plant, etc., storing the energy as hydrogen, which could then be used as fuel in household generators, vehicles, etc. Yes, there would be a net drain on energy to make the hydrogen. But making it where there’s a wealth of energy available, then burning it where energy is needed, would be an efficient way to store and transmit power. ---
**Author:** ![Fear\_Itself](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fear_itself/32/19637_2.png) [@Fear\_Itself](https://boards.straightdope.com/u/Fear_Itself)\ **Post date:** [October 20, 2004, 4:55pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/8 "2004-10-20T16:55:55Z")
> [@jebert](#): > > However, a friend of mine claims that the manufacture of hydrogen requires natural gas as a feedstock, and that that renders the whole hydrogen effort a pipe dream. Why is hydrogen from NG a pipe dream? The US has the [world’s seventh largest proven reserve of NG](http://www.infoplease.com/ipa/A0872966.html), and [by some estimates](http://www.naturalgas.org/overview/resources.asp), undiscovered reserves and other sources of NG in the US could be as much as seven times that amount. ---
**Author:** ![Spectre\_of\_Pithecanthropus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/spectre_of_pithecanthropus/32/12343_2.png) [@Spectre\_of\_Pithecanthropus](https://boards.straightdope.com/u/Spectre_of_Pithecanthropus)\ **Post date:** [October 20, 2004, 4:56pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/9 "2004-10-20T16:56:06Z")
> [@Grey](#): > > If you’re concerned about climate change/forcing then that’s almost obviously a good thing. People, being people will likely then begin to complain about increased cloud cover or something though. 🙂 I wonder if there are climate change implications here. If everybody in the huge cities of the dry Southwest could drive a hydrogen car, would that lead to increase precipitation? That’d sure help in our part of the country, though possibly not at this exact moment as we seem to have enough for today. > [@](#): > > Ultimately hydrogen is not an energy source it’s an energy holder. You use a primary energy source such as hydrocarbons, solar, fission, or fusion to generate power and then you store it, at a loss, within the hydrogen you create. Of course Bush never mentions this fact; but still there’s supposedly an advantage to using hydrogen fuel techology. Essentially, instead of the situation today, where we have a huge variety of vehicles, all burning HCs at different rates of efficiency and cleanliness, we’d use the HCs in central hydrogen production plants, where economy of scale would be achieved along with the maximum possible control of pollution. Considering, though, that the average car seems to remain on the road for at least 10 years, there’d be a long way to go even if the technology were perfected today. ---
**Author:** ![Fear\_Itself](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fear_itself/32/19637_2.png) [@Fear\_Itself](https://boards.straightdope.com/u/Fear_Itself)\ **Post date:** [October 20, 2004, 5:15pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/10 "2004-10-20T17:15:00Z")
> [@Grey](#): > > Ultimately hydrogen is not an energy source it’s an energy holder. You use a primary energy source such as hydrocarbons, solar, fission, or fusion to generate power and then you store it, at a loss, within the hydrogen you create. By your definition, gasoline is not an energy source either, as it must be refined from crude oil with a loss of energy. Hydrogen is a fossil fuel. ---
**Author:** ![Colophon](https://avatars.discourse-cdn.com/v4/letter/c/f05b48/32.png) [@Colophon](https://boards.straightdope.com/u/Colophon)\ **Post date:** [October 20, 2004, 5:26pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/11 "2004-10-20T17:26:10Z")
There is also research being done on using bacteria and algae that will generate hydrogen. This could possibly provide energy that is “free” to some extent. Lost of stuff about this on Google. Sample page: [http://www.energycooperation.org/bioproductionH2.htm](http://www.energycooperation.org/bioproductionH2.htm) ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [October 20, 2004, 5:33pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/12 "2004-10-20T17:33:43Z")
> [@Fear Itself](#): > > By your definition, gasoline is not an energy source either, as it must be refined from crude oil with a loss of energy. > > Hydrogen is a fossil fuel. Depends on the source I suppose. Gas is an energy holder just like hydrogen generated from steam reforming. So is oil since it’s simply stored solar energy. But water derived hydrogen could hardly be called a fosil fuel. ---
**Author:** ![Padeye](https://avatars.discourse-cdn.com/v4/letter/p/a9a28c/32.png) [@Padeye](https://boards.straightdope.com/u/Padeye)\ **Post date:** [October 20, 2004, 5:47pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/13 "2004-10-20T17:47:10Z")
> [@Spectre of Pithecanthropus](#): > > IOf course Bush never mentions this fact; In all fairness to Shrubya this is rarely mentioned by any proponent of hydrogen fuel. I haven’t seen it often discussed outside of SDMB. ---
**Author:** ![chrisk](https://avatars.discourse-cdn.com/v4/letter/c/6de8d8/32.png) [@chrisk](https://boards.straightdope.com/u/chrisk)\ **Post date:** [October 20, 2004, 5:55pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/14 "2004-10-20T17:55:59Z")
> [@Grey](#): > > So yes, if we use hydrocarbons as hydrogen sources then we will run out of the stuff sooner or later. The emissions from the cars, however, will simply be water vapour. If you’re concerned about climate change/forcing then that’s almost obviously a good thing. People, being people will likely then begin to complain about increased cloud cover or something though. 🙂 Out of curiosity, do you know what they generally do with the CO2 created as a side effect of the hydrogen creation process? If you released that into the atmosphere it’s greenhouse gas, just as much as if you were burning the fossil fuel directly. I can imagine that there would be almost no particulate matter and much less noxious gas though. ---
**Author:** ![krisolov](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/krisolov/32/3724_2.png) [@krisolov](https://boards.straightdope.com/u/krisolov)\ **Post date:** [October 20, 2004, 6:15pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/15 "2004-10-20T18:15:34Z")
There are also membrane based technologies which allow the seperation of hydrogen from H2-rich feedstock gases; IIRC this is used sometimes in the steam reforming process referenced above. ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [October 20, 2004, 6:26pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/16 "2004-10-20T18:26:04Z")
> [@Spectre of Pithecanthropus](#): > > but still there’s supposedly an advantage to using hydrogen fuel techology. > > \ > > Considering, though, that the average car seems to remain on the road for at least 10 years, there’d be a long way to go even if the technology were perfected today. Aside from cleanliness issues there are simple practical issues to going to a hydrogen fuel technology. > [@](#): > > Using these data (estimated reserves: 800 billions of barrels, world consumption: 76 millions per day), it looks like planet Earth has have oil for about 10,000 days, i.e. about 27 years. Assuming that consumption does not increase… If consumption increases an average 5% a year, then we have oil for about 15 years. But the US Geological Survey estimates the amount of oil that is still to be found at about 3 trillions, three times the oil reserves known today (it is not clear if “all” that oil can actually be pumped to the surface and therefore used). The real issue is when will production be insufficient to cover demand? That largely depends on demand, not on reserves. > > World oil consumption has remained constant at an average 4.47 barrels per capita between 1981 and 2001. > > SOURCE: [World Oil Production](http://www.scaruffi.com/politics/oil.html) By the estimate of cars lasting 10 years we are only a few generations away from oil using vehicles going the way of the Dodo. The quote above does mention a massive amount of oil yet to be found but as also mentioned extracting it all may not be possible. Even if it is possible it will be more expensive to do thus raising prices on fuel and therefore putting more momentum behind alternate energy technologies. Remember, oil won’t just be pouring out of wells full bore and then one day shut off. You’ll see a gradual decrease of oil fields still in production (I used to have a nifty link that showed how various countries would start dropping off oil production but cannot find it). As the supply dwindles again you will get higher oil prices and again see momentum gather behind alternate energy technologies. Hydrogen of course is virtually limitless for our purposes. If that extra 3 trillion barrels cannot be found or gotten at cheaply I’d guess most everyone will perforce be in an alternate energy (likely fuel cell) car by 2030. Subtracting the ten year auto lifecycle then around 2015-2020 expect to see the switch starting to take place in earnest. There are a lot of cars out there that need replacing. ---
**Author:** ![Spectre\_of\_Pithecanthropus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/spectre_of_pithecanthropus/32/12343_2.png) [@Spectre\_of\_Pithecanthropus](https://boards.straightdope.com/u/Spectre_of_Pithecanthropus)\ **Post date:** [October 22, 2004, 5:12pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/17 "2004-10-22T17:12:26Z")
I had said that Bush, when touting the hydrogen economy, never mentions that the energy to make hydrogen has to be gotten somewhere. > [@Padeye](#): > > In all fairness to Shrubya this is rarely mentioned by any proponent of hydrogen fuel. I haven’t seen it often discussed outside of SDMB. Which only goes to demonstrate that we’re the wisest, most perceptive people on the planet :D. Very little indeed escapes the keen gaze of our perspicacity. Only Dopers should have the vote! ---
**Author:** ![Inigo\_Montoya](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/inigo_montoya/32/124_2.png) [@Inigo\_Montoya](https://boards.straightdope.com/u/Inigo_Montoya)\ **Post date:** [October 22, 2004, 5:53pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/18 "2004-10-22T17:53:18Z")
> [@Whack-a-Mole](#): > > By the estimate of cars lasting 10 years we are only a few generations away from oil using vehicles going the way of the Dodo. I heard this in the mid 70s. I’m hearing it again now–but with the same timeline of “10-15 years until d-day.” Nuts I say. As long as we WANT hydrocarbon-powered vehicles, we’ll GET the fuel even if it means turning turkey guts into petroleum. I just can’t get worried about it. Same principle applies to marvelously efficient solar arrays–as soon as we decide we want them, they will happen. But still I’d like to see another power source developed, and hydrogen looks neat. Solar power is abundant, and so is sea water. And they even converge fairly frequently. But even if we limit our solar-powered hydrogen factories to nice sunny beaches, there’s still the byproduct of oxygen. When does THAT become a problem? Or can you use the byproduct oxygen to fuel a steam/electric plant to augment the water seperation process? You’d be pulling hydrogen out of the air to burn it, but you wouldn’t really need anything more high tech than a fan for that. ---
**Author:** ![Grey](https://avatars.discourse-cdn.com/v4/letter/g/b782af/32.png) [@Grey](https://boards.straightdope.com/u/Grey)\ **Post date:** [October 22, 2004, 6:09pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/19 "2004-10-22T18:09:51Z")
Since the hydrogen was originally bound to the oxygen I’m not sure how there could be an increase in atmospheric oxygen once your burn the hydrogen. Localized concentration of oxygen may be an issue though. ---
**Author:** ![Fear\_Itself](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/fear_itself/32/19637_2.png) [@Fear\_Itself](https://boards.straightdope.com/u/Fear_Itself)\ **Post date:** [October 22, 2004, 6:15pm UTC](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235/20 "2004-10-22T18:15:06Z")
> [@Inigo Montoya](#): > > But still I’d like to see another power source developed, and hydrogen looks neat. Solar power is abundant, and so is sea water. And they even converge fairly frequently. But even if we limit our solar-powered hydrogen factories to nice sunny beaches, there’s still the byproduct of oxygen. When does THAT become a problem? Or can you use the byproduct oxygen to fuel a steam/electric plant to augment the water seperation process? You’d be pulling hydrogen out of the air to burn it, but you wouldn’t really need anything more high tech than a fan for that. If your high-tech fan ( :eek: ) can just pull hydrogen out of the air, why do we need fancy solar-powered hydrogen factories with their vexing oxygen waste products? [Next page](https://boards.straightdope.com/t/how-do-we-make-hydrogen/270235.md?page=2)