Pee Power: It’s No Joke (No, Honestly; We Really Mean It This Time)
Quite a few years ago, when this blog site was just starting out, we published an April Fool’s day article that claimed that scientists had worked out how to run a car engine on pee. We intended this as a joke but it looks as though the last laugh’s on us. There really is a way to run a vehicle on urine.
This is not to say that the white-coated ones have come up with a system by which you refuel your vehicle by taking a very, very large drink of water then… well, use your imagination! Instead, it’s a system where hydrogen is extracted from urine and is then used in hydrogen fuel cells to power a vehicle.
In fact, according to Gerardine Botte of Ohio University, who developed the process of getting hydrogen out of urine in 2009, it’s easier to get the hydrogen out of wee than out of water. In urea (one of the compounds of urine), there’s four hydrogen atoms per molecule rather than two, and they’re not holding chemical hands as tightly, so they’re easy to split off with a cheap little nickel-based electrode that uses 0.37 V to grab the hydrogen rather than the 1.23 V needed to split water up into H2 and O.
This is very good news for the sustainable fuel world. Hydrogen fuel cells are the next big thing. In fact, Toyota , the people who really popularised the hybrid electric vehicle with the ground-breaking Prius are set to launch the world’s first mass-produced fuel cell vehicle, known as the Mirai (which has already been released in Japan and California).
So how does hydrogen fuel cell technology work?
A fuel cell is kind of like a battery in that it produces an electrical current that can then be used to power a motor. However, unlike a battery, it needs to be supplied non-stop with fuel, which is usually hydrogen and water. There are several different types of fuel cell out there but in general, what happens is this:
- Hydrogen molecules flow in at one side and the anode catalyst nicks their electrons (a hydrogen atom contains one proton and one electron). This leaves the hydrogen molecules with a positive electrical charge, while the electrons start the circuit buzzing.
- The positively charged hydrogen molecules are pulled through the electrolyte towards the cathode.
- At the cathode, the positively charged molecules meet up with the electrons again. They also meet up with oxygen molecules that have been coming in the other way.
- The oxygen, hydrogen and free electrons react and produce H2O, which leaves as exhaust.
If you want this in more visual form (and don’t mind a little promo material), watch Toyota’s explanation here:
Each individual fuel cell only produces a wee bit of electrical current, so to be really efficient, you need a whole bank of them.
The main snag with hydrogen fuel cell vehicles so far is the usual problem with any new technology: the infrastructure problem. Hybrid and plug-in electric vehicles are already facing this problem, namely the issue of “topping up”. One of the problems that will have to be overcome is that it’s not a wise idea to have large amounts of pure hydrogen hanging around for any length of time as it’s really, really explosive (heard of the Hindenberg disaster, anyone?). However, seeing as we can cope with other highly flammable materials like LPG, acetylene and even petrol, this shouldn’t be too much of a problem.
The other issue is getting the hydrogen. Yes, it’s an abundant molecule but it tends to be tied up to other molecules so it has to be stripped off. Methane is a commonly used potential source of hydrogen, but you have to get the methane from somewhere, usually as a waste product of industries such as our sugar cane industry. Extracting the hydrogen for use as fuel is fiddly compared to just producing and pumping ethanol from the same source, so it’s usually the ethanol that wins out.
This is kind of why the discovery that you can get the hydrogen out of urea pretty easily is rather exciting, especially as the leftover molecules after you’ve removed the hydrogen are nitrogen molecules, which have potential to be used as fertiliser (in fact, urea is currently used as fertiliser, as any old-fashioned home gardener will tell you). Let’s face it: if there’s one thing we’re not going to run out of in a huge hurry is pee. If we’ve got an increasing human population and we all have to keep drinking, then we’re all going to widdle. In fact, as an extra bonus, if we’re all saving our pee to use in a fuel cell vehicle, this will reduce pressure on the waste water system which means that there will be more water for use in agriculture and for drinking, which will help reduce world hunger, etc. etc. Human pee isn’t the only source, either, as the process works with just about any sort of urine, including cow, sheep and horse pee.
Hydrogen fuel cell technology has been tried in Australia when Perth was trialling a set of buses running on hydrogen. Here, we’re lagging behind the US, Germany, Japan and the UK somewhat. Perth had the only hydrogen fuelling station for the now-discontinued bus trial.
It’s all rather exciting, really, as there’s plenty of potential. Here’s to Pee Power!
Safe and happy driving,
Megan
Bill says:
Why was the Perth Hydrogen powered bus trial discontinued? If Hydrogen was available there must be some other reason for the trial to be terminated early. This new technology sounds exciting but sometimes the devil is in the detail. And producing large amounts of Hydrogen for retail sale at fuel stations is not an easy logistical exercise either. I also would rather not be involved in a serious crash inside a car carrying a large cylinder of compressed Hydrogen. A much better technology, which has yet to appear, is to transmit electricity to motor cars by wireless transmission. Whoever comes up with this technology will become richer than the founder of Microsoft. And don’t poo pooh this idea, it is only a matter of time before it becomes reality.
March 29th, 2016 at 2:39 pm
les says:
you obviously do not do much research into your subject,
the world leaders in hydrogen power are hyundai / kia motor corporation surely? They have a hydrogen tuscon on the market for $ 50,000+ they are not thinking about it you can buy it.
March 29th, 2016 at 6:48 pm