Burning coal produces only CO2, no water. Coal is mostly carbon. It can't produce much H2O, because there's little hydrogen in the original fuel.
Originally Posted by GneissGuy
That's because coal is a rock which contains some hydrocarbons and a lot of other things. Hydrocarbons aren't the only things that are combustabile. You can burn pure carbon: C + O2 -> CO2 (which is part of the coal burning process). I noted that I was referring to hydrocarbons, which is relevant to the bloom box, in which case, the process for complete combustion of methane, (the main component of natural gas) with 100% efficiency is:
CH4 + 2O2 -> 2H_20 + CO2
As a reference see:
http://en.wikipedia.org/wiki/Combustion
which repeats what I said earlier:
``When a
hydrocarbon burns in oxygen, the reaction will only yield carbon dioxide and water.''
... Hydrogen fuel produces only water, no CO2.
Hydrogen is not a hydrocarbon.
Natgas probably produces the least amount of CO2 from any hydrocarbon because it has the highest percentage of hydrogen in the original fuel.
Your missing the point and comparing apples to oranges. The point is that if you pick a hydrocarbon, which in the case of the bloom box, means methane, complete combustion (or 100% efficiency) produces only CO_2 and water in the proportions given above. The heat produced (or absorbed) in ANY chemical reaction depends only on the difference in binding enegies of the reactants and products.
For a hydrocarbon, that means the reactants consist of a hydrocarbon (a molecule consisting of carbon and hydrogen) and the products produced with a given amount of oxygen. If you supply enough oxygen for complete combustion (100% efficiency) you get water and carbon dioxide.
Not necessarily. Even if two devices consume the same amount of fuel and produce the same amount of the various exhaust gases, they can produce different amounts of electricity.
Even if the burner produces the same amount of heat, the electricity output can vary.
If the chemical reactions are the same (which is implied by your statement regarding the same fuel and same exhaust gases, the heat energy produced is the same whether you do it with a bloom box or a match.
However, the only thing bloom energy has made public is that methane (or whatever) goes in and electricity comes out. Therefore, the only thing one can say with any certainty is that the efficiency for the reaction of methane and oxygen can't be more than 100% efficient and for 100% efficiency, it produces the maximum amount of CO2 and water it can produce. Anything more is complete speculation.
If you follow the info they've published, the basic science is pretty clear. It's a ceramic electrolyte natgas powered fuel cell. Other people have made ceramic fuel cells before. The exact chemicals of the cathode, anode and electrolyte may be secret.
How can the science be clear without the secret information? Once you give the benefit of the doubt to the vloom box and assume the methane and oxygen is used with 100% efficiency, the secret information is the only thing relevant to any other claims about the bloom box.
Also you (I think) stated something about the bloom box not using the Carnot cycle. That makes their claims stranger still. The Carnot cycle is the most efficient process you can create without violating the second law of thermodynamics (and creating a perpetual motion machine). Other cycles can have the same efficiency, but not using the Carnot cycle is not an argument that implies the bloom box could be more efficient in not doing so.