I remember that one of the members here (I think it was James), mentioned how glass LED bulbs are filled with helium to conduct heat away from the led cobs or filaments, since a traditional heat sink cannot be used while maintaining the aesthetics of a glass bulb. I understand helium is used owing to its high thermal conductivity. How could the price of glass LEDs change if the helium prices rise, or the environmentalists have their way and shut down oil wells, as helium is primarily produced as a byproduct of oil and gas drilling? Could hydrogen be substituted for helium, disregarding the danger of fire and accounting for its slow leakage from the bulb in relation to the lifespan of the bulb?

I could see them switching them to hydrogen. It's not that dangerous when it's not mixed with oxygen, and in the event the lamp gets broken and the gas gets ignited from sparks, all that would happen is a small fireball that dissipates in less than a second. There are things that are much more likely to start a fire in your house than that.

Yes, but hydrogen is not inert like helium. I could see where the hydrogen would react with something in the lamp (not oxygen) and give trouble. Maybe another inert gas would be more appropriate, such as neon or krypton.

I dont think there would be that much Helium shortage. It could be majority is obtained as a byproduct from oil wells, but not because it is the only source.
There is enough Helium in the air to allow it to be distilled from it. It may be a bit more expensive, but by far not prohibitively.
The technology is in place, mabe just not used for Helium extraction (because of the cheaper competition).

Yes, but hydrogen is not inert like helium. I could see where the hydrogen would react with something in the lamp (not oxygen) and give trouble. Maybe another inert gas would be more appropriate, such as neon or krypton.

Neon and Krypton have far lower thermal conductivities than helium or hydrogen, as do most other gases, so I don’t think they would work that well.

I dont think there would be that much Helium shortage. It could be majority is obtained as a byproduct from oil wells, but not because it is the only source.
There is enough Helium in the air to allow it to be distilled from it. It may be a bit more expensive, but by far not prohibitively.
The technology is in place, mabe just not used for Helium extraction (because of the cheaper competition).

Helium boils at -268.9 degrees centigrade, just slightly above absolute zero. I think the process of extracting it would be cost prohibitive, considering how expensive and energy intensive air liquification and distillation is. It’s far more abundant than krypton 0.0005% versus 0.0001% respectively, but the temperatures involved might be too extreme to be economical. I’m wondering if the cost would be high enough to make it justifiable to use hydrogen, since it can easily be made from the electrolysis of water. I could see problems with its utilization due to similar effects that occur in hydrogen thyratrons, as I’ve heard its hard to keep the gas contained, but the bulbs only need to last 10000 hours or so, so it could be doable.

It is actually way easier to contain the hydrogenthan Helium. Hydrogen is in two atom molecules, which are way larger than the single He atoms.
For the cooling, the H2 is half of the mass compare to He, so carries the heat even better.
But the possibility of a fireball with H2 is something that would make it rather problematic, mainly for home use.

Yes, extracting He from air is expensive, but because there are many gas products sold from the single air distillation cycle (N2, O2, Ar and many others), the distillation cost is paid in big part by these. What the He extraction would have to pay for itself is the extra steps needing to fizzle the dissolved He from the liquid air (before it goes to the distillation of the rest). For the cooling purpose, the He does not have to be that much clean, so not much further processing is needed (unlike for e.g. welding use, where you need 99.9+ purity).

But He is already very expensive gas to start with, the extraction from natural gas is not much cheaper either. It needs similar distillation, which is by itself even more expensive (because of the flamability of the material and because there are not much other byproducts to sell, beside the LNG itself), the only factor making the He a bit cheaper from this source is its higher concentration there.

What about Nitrogen? I thought it was already used in lamps.

What about Nitrogen? I thought it was already used in lamps.

It is too heavy gas to be a good convection heat transmission medium. You need as light gas for it as possible. Hydrogen carries the heat the best but it is flamable, second best is the Helium.
Then Neon would be the 3rd (still about half mass compare to air).
Then the next is plain air - the LEDs do not run hot enough for the oxygen to be of any problem...

By the way water vapor would be the same as Neon, if it were gas with high enough pressure at the operating temperatures, so practically usable only above 100degC.

This is an extremely good question!

The only suitable gases for filling the present generations of gas-cooled LED lamps and modules are helium and hydrogen, and mixtures thereof.  For a while there were concerns about helium supply, because indeed practicaly the entire global supply does come as a byproduct of the natural gas and oil extraction.  Distillation from the air is completely unviable due to the exceptionally low percentage of helium.  Moreover, Helium is one of the very few elements which are physically lost from our planet over time - gravity is not sufficient to maintain this at ground level in the atmosphere, so the yields from fractional distillation of air are pathetically low. 

Currently the price of helium is not too bad.  This is thanks to the US military who had been stockpiling much of the helium extraction for the past few decades, to fuel its zeppelins project, which was recently axed.  Recently they began selling off much of the reserve.  So although the cost of helium extraction has been increasing, the market selling price has been decreasing.  By the time this situation ends, it is expected that the efficiency of the LED filaments will have increased again, such that they generate less heat and can be air-cooled.  Indeed in the USA you can already find air-cooled LED filament lamps for sale.  Their efficacy and lifetime is of course much lower than the more standard helium types, but they are also cheaper due to no need for flame-sealing and vacuum pumping of the lamps.  Their efficacy still compares favourably with standard metal-cooled and plastic-bodied LED lamps.

Hydrogen is a tricky subject.  So long as the gas in the lamp does not contain any oxygen they are safe.  However all kinds of lamps are plagued by a small percentage of leakers as production defects.  If a small amount of air leaks into the bulb, and there is a poor electrical connection or power surge or a filament burns out and creates a spark, the result is not pleasant.  This has already been tested, and the force of the explosion can be particularly violent.  The holes in the ceiling of one of my labs are a constant reminder of what happens when these gases mix inside a lamp!  So I am not sure any manufacturers will knowingly put pure hydrogen lamps on the market.  It is also hazardous in production.  The lamps are sealed off from the exhaust machine by melting the glass exhaust tube with a flame, and sometimes the glass tube cracks.  The last thing you want is for the tipping flame to then ignite the gas inside the bulb.  There are some partial ways around this, by mixing the hydrogen with other gases to ensure that if some oxygen does leak in, it cannot reach a concentration that would lead to a dangerously powerful detonation.  There is already one LED lamp on the market in Europe which contains a 60:40 Helium:Hydrogen mixture.  This provides better cooling than pure Helium and was necessary to achieve the 1521 lumen / 100W equivalency in a standard A60/A19 size bulb.  The latest LED filament G9 and R7s halogen-replacement capsules also tend to have some hydrogen component in the filling.  But those are made from quartz which is porous to both hydrogen and helium which diffuses out rather quickly, hence the poor life of those types.

Why don’t they switch back to glass instead of quartz?

Also a good question!  Glass cannot be worked quickly - it has to be heated up gradually to its melting temperature, and then slowly cooled down to anneal out the stresses.  With a compact lamp the LED filament needs to be brought close to the end seals, and the necessary heat levels destroy its plastic parts.  Quartz however can be heated up very rapidly, and immediately after sealing it can be immersed in liquid nitrogen to quickly take the heat back out.  Although the softening temperature is much higher, the whole process can be so fast that the LED filaments are able to survive that thermal exposure.

how interesting sincerely!