greenhouse green house and co2

Should i use something to create co2 in my greenhouse? Would a litle ethanol fireplace do the trick and would my chilli plants love it?
It's a bit tricky without a controller and a closed environment. Over production from open combustion is a huge risk, CO2 rising to exceed 1200-1500ppm, coupled with a lack of heat control (integral to implementing higher CO2 levels), creates the potential to wreak havoc e.g. CO2 toxicity damaging the plants, incomplete combustion resulting in CO and ethylene production. Proper air movement is an issue, you would need to install oscillating fans to evenly distribute CO2 and prevent settling.
As well, greenhouses are not sealed well, and will leak CO2 like a sieve. It is possible, if you're savvy with math and chemical reactions, to predict the consumption rate of the plants, monitor and record the leak rate of the greenhouse and use that to model the combustion of the ethanol.
With a cheap CO2 tester and a small burner with a control valve, you could find a safe sweet spot of say 600-800. I would highly recommend using a CO alarm as well. A more advisable method are the DIY fermentation buckets, that are cheap, safe and somewhat predictable, though in a normal sized greenhouse you're going to consume hundreds of pounds of sugar. As well, any grow store sells mycobags (you would need a lot) and other novelty CO2 producers, but then you're paying out the nose.
Not as easy as it looks, and there is the potential to kill yourself, your plants, or better yet, someone else.
Truthfully though, it all seems a little convoluted (though some people love to tinker), dangerous and expensive, unless you're growing cannabis.