sometimes you have a tone of heat at the end of a level, and it just doesnt have anywhere to go. your eqiupment is all level ten, your weapons and amour and it simply just goes no where.
Heat Brewing, you will have a bottle or other form of container, which can be opened at the start of the level or anywhere in it which collects the Heat you have at the end, you close the lid/ bottle top and youve got a brew of heat. this could be selled to other knights or a merchant or both, (both preferably), giving you a little extra while helping someone else fill their items heat bar. they can also be usd on unbound eqiupment or to sell or trade. can also be used on unbound eqiupment.

questions you may have?

1Q- how much would it cost to buy a bottle?
1A- it would be around 500 to 1000 crowns, knights selling this shouldnt have to pay too much for a container and it shouldnt be too much for people buying either.

2Q- if people wanted extra energy, wouldnt they just use the heat amplifier instead?
2A- using the heat amplifier is more, it may get you more energy over a long period of time, but really an instant effect would come in handy. espicially when you havent got any ce, which is another reason why a container should not be too pricy and over the energy prices on the market losing the plot, so its cheeper and easier to get, instant, and would give the seller a reason to smile as well.

3Q- how would people know how much Heat is in a bottle without being ripped off?
3A- people would know as there would be a heat rating, like a heat bar to show amount or maybe a level. when trading or in the auction house, simply dragging the mouse over it and keeping it there, like you would for viewing weapons, armour etc.

4Q- how long does it last?
4A- it would be a usable and therefore permanntly in your arsenal untill sold. it may be activated anytime on the level, before you get on the elevator. when you do get on, it will bottle your heat to be saved for later, again as a permanant usable. how much heat

5Q- if someone wanted energy, wouldnt this idea kind of ruin the idea of selling it?
5A- no, it wouldnt as if your out of ce and you want to up grade your new item still, but dont have one already filled then you would buy one.if it still doesnt work out then a new merchant or improved merchant in haven, (idealy boost), then hes willing to but for more then the container itself.

6Q- wouldnt it be more usefull if it was activated over a length of time?
6A- maybe it would, but should still be limited to a number of levels, idealy 3. or perhaps the containers could come in different sizes, and each last a different length of levels. example, small bottle- 1 level, medium bottle-2 levels, large bottle- 3 levels.
either this or the bottle closes when it reaches a certain point, also solving how much energy is in each one to prevent buyers being ripped off. different size bottles would be able to get different amounts of heat before its topped (had the lid put on).

The thought of it closing when its reached its full, sounds good to me. should have 3 sizes though, either way, should not be over energy prices to ensure fair deals. May mostly sound like a buisness but can be used on your own eqiupment later, would not ruin getting heat in future as containers will be roughly 1 levels worth in a small size, 2 levels worth in a medium and 3 in a large.