Good reasoning and I think valid.Coalfire wrote:Nothing personal and I'm not going to try and argue it cause your mind is made up and that is how it is. I don't understand this two story house and basement stuff, see you will have to explain that to me size and temp that your are trying to achieve with your 50lbs of coal. Like someone said are you heating a 4000sqft corn crib or a 1500sqft house? You said 50lbs of coal 50x13000= 650,000btu per day if you get every last ounce out of the coal 650000/24= 27,083btu/hr average. so your are saying I could put a 30K BTU space heater in the basement of a two story house and heat it comfortably on a sub zero day?
Looking at it another way with my own house which is a raised ranch built in 1990 with good insulation I burned 600 gallons of oil per year. This was with keeping the lower level at 55 and the upper level 64to 65 degrees. In my area there are about 6500 degree days per year. Dividing that by 600 means I burn a gallon of oil for every 10.8 degree days. A degree day is the average temperature for the day subtracted from 65. So on a day that averages zero there are 65 degree days divided by 10.8 and I would burn 6 gallons of oil. 6 times140,000 = 840,000 BTU divided by 24 hours = 35000 BTU per hour times .80 oil burner efficiency =28,000 BTU per hour to heat the house to the temperatures indicated above on a zero average day which is 60 degrees average for the whole house. So for each degree of heat I burn 467 BTU per hour. To raise the average temperature to 70 I would need to burn an additional 4670 BTU for a total of 32,670 BTU per hour. Actually the figure would be higher since the heat loss of the house would be higher at 70 degrees, probably more like 35,000 BTU.
In a 2 story plus basement I would guess the figure to be more like 50,000 BTU.