See the first two links for some information about oxygen concentrators and oxygen generators. They all take power to run, but some run more efficiently than others. If this Idea is adopted, then we can be sure that research funding will increase, seeking efficient ways to extract oxygen from the air.

An ordinary combustion engine burns a fuel in air (compressed air in internal combustion engines). There are often two undesired results. One is that some portion of the fuel doesn't always get burned, which means the engine produces less power than we want. The other is that nitrogen in the air will sometimes combine with some of the oxygen. That's bad both because it is an energy-absorbing chemical reaction (reduces total engine power), and the result is a pollutant.

But what if the ratio of oxygen to nitrogen was increased from the usual/approximate 1:4? What if it was 1:1 or even 10:1, thanks to an oxygen concentrator? All the fuel would get burned! (No unburned fuel, even with Diesel engines!) Indeed, extra fuel could get burned, although heftier explosions inside internal combustion engines would likely require stronger cylinders.

With respect to nitrogen-oxide production, this might go up if there was plenty of oxygen left over, after the fuel burned. The obvious solution there, though, is to not feed any ordinary air into the engine; just feed pure oxygen from the oxygen generator, instead.

Which brings us to a new question, because as mentioned near the start of this Idea, it takes energy to run an oxygen generator. Will the greater power produced by the engine be enough to pay that energy cost, especially after researchers focus on finding ways to extract oxygen from air very efficiently? To Be Determined!
-- Vernon, Dec 19 2016

Oxygen Generator Oxygen_20generator
As mentioned in the main text. [Vernon, Dec 19 2016]

Oxygen Generator 2 Oxygen_20Generator_202
As mentioned in the main text. [Vernon, Dec 19 2016]

[bigs] it would be more efficient not to use the intermediate step of a H and O generator, and a combustion chamber, by just using some kind of ingenious crank system to couple one end of the drive shaft to the other. The downside is that there would be less spare heat for cooking, but I think the efficiency savings should make up for that.
-- pocmloc, Dec 19 2016


//2 litres of oxygen for 100 W// Is that 2 litres per hour, or per minute?
-- MaxwellBuchanan, Dec 19 2016


Pressure-swing (sorbtion) oxygen concentrators are commonly referred to as "Low-rate oxygen generators" for a very good reason.

Internal combustion engines ingest huge amounts of air. Oxygen isn't necessarily the issue. If you need more oxygen, grab more air. The nitrogen isn't irrellevant - it's important reaction mass (working fluid).

In an engine operating under stable conditions - a fanjet at high altitude is an excellent example - there's very little unburned fuel. Engine designers go to a lot of trouble and effort to ensure this. Unburned fuel = higher running costs.

// heftier explosions inside internal combustion engines //

... don't happen. Detonation is a very, very bad thing and will destroy the engine almost instantly. What happens is controlled combustion. A stoic mixture that's compressed and then ignited is Game Over for the engine.
-- 8th of 7, Dec 19 2016



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