NoFossil Wood Heat Planning Tool

Enter values for your location and situation in the form below and click 'Submit'. This tool will query the NOAA forecast database and calculate heat loads for the next 48 hours based on your settings. Bookmark the results and you will not have to re-enter data on subsequent visits.

Cloud cover and solar gain are not yet taken into account.

Disclaimer: Use of this site is at the sole risk of the user. Results may not have any correlation with objective reality. Frostbite and marital discord have been reported as possible side effects. Use at your own risk.

Latitude: Latitude and Longitude are decimal numbers such as 44.32. West Latitude is a negative number. Get values for your location from ZipInfo or other source. Only works for USA - sorry....
Longitude:
Base Load: The portion of the heat load that is relatively constant and independent of temperature. Domestic hot water would be an example. A typical family might have a base load in the range of 40,000 to 70,000 BTU/day.
Wind Factor: The number of degree days to add for each mile per hour of wind. This depends on house siting and a variety of other factors. A value of 0.2 would be typical.
Temperature Factor: This is the most critical value. This is BTU loss per degree day. There are heat loss calculators available on the web, or past history of fossil fuel consumption can be used. Typical values might be 5000 to 30,000.
Boiler Output: The actual average heat delivered per hour over the course of a typical burn. It's generally about 75% of the rated capacity of the boiler.
Degree Day Base: The temperature from which degree days are calculated. 65 is the most common number. Houses with good insulation and southern exposures may get better results with a lower value.

Time:7AM 10AM 1PM 4PM 7PM 10PM 1AM 4AM 7AM 10AM 1PM 4PM 7PM 10PM 1AM 4AM 7AM
Time:7 10 13 16 19 22 1 4 7 10 13 16 19 22 1 4 7
Temp:13 21 28 29 26 24 22 22 22 29 35 36 32 29 26 24 23
Wind:2 2 5 6 5 5 3 3 3 5 6 5 6 4 5 5 5
Temp (adjusted):13 21 27 28 25 23 21 21 21 28 34 35 31 28 25 23 22
Cloud:12 0 0 11 14 36 26 10 22 10 10 10 0 0 7 8 17
Hourly BTU Load:19452 16486 14112 13816 14854 15596 16189 16189 16189 13742 11591 11146 12703 13668 14854 15596 15967

Next 24 hours:
Degree days = 37
burn time = 7.3
24 hours BTU load = 380085
Hourly load=15836

Following 24 hours:
Degree days = 34
burn time = 6.8
24 hours BTU load = 354052
Hourly load=14752