Worst paragraph ever!
Are There An Instrument To Measure BTU's In A Controlled Environment (oven), Of Different Fuel Sources?
A calorimeter is used to measure the heat of such things as chemical reactions, thermal changes, or heat generation capacities. It does this within a sealed chamber, so that all heat generated is measured without influence of ambient heat from outside or loss of heat inside.
However, determining the btu's of something like an oven is a trickier prospect, as several factors had to be accounted for... Not just temperature, but also volume of the chamber being heated, as well as heat that is lost thru the walls of the chamber (which means calculation of thermal absorption rates of the materials the chamber is made of). Some pretty heavy math involved in that. One can calculate a theoretical BTU of, say an oven, based upon the current that is consumed and the resistance of the heating element... But it is a guideline only as it will not accurately reflect the true temperatures within the oven (because of the aforementioned heat loss.
However, determining the btu's of something like an oven is a trickier prospect, as several factors had to be accounted for... Not just temperature, but also volume of the chamber being heated, as well as heat that is lost thru the walls of the chamber (which means calculation of thermal absorption rates of the materials the chamber is made of). Some pretty heavy math involved in that. One can calculate a theoretical BTU of, say an oven, based upon the current that is consumed and the resistance of the heating element... But it is a guideline only as it will not accurately reflect the true temperatures within the oven (because of the aforementioned heat loss.