Quick Answer
Calculate the required BTU by multiplying the square footage of your off-grid space by the desired temperature increase, then multiply by 25, and consider a 10% safety margin.
Gathering Space Data
To calculate the required BTU for heating your off-grid space, start by gathering essential data. Measure the square footage of the space, including any areas that will be heated such as living rooms, bedrooms, and hallways. Consider the insulation and construction of the space, as well as the desired temperature increase. For a standard temperature increase of 68°F (20°C), the required temperature increase will be 20°F (10°C) in colder months.
Calculating Required BTU
Using the calculated square footage, multiply it by the desired temperature increase (in this case, 20°F or 10°C). Multiply the result by 25 BTU per square foot per degree. For example, a 1,000 square foot space with a 20°F temperature increase would require 50,000 BTU. To account for a 10% safety margin, multiply the result by 1.1, bringing the total required BTU to 55,000 BTU.
Heater Selection and Efficiency
When selecting a propane heater for your off-grid space, consider its efficiency and BTU output. A common propane heater with a 40,000 BTU output will be sufficient for a 1,000 square foot space. However, if you live in an area with extremely cold temperatures, consider a more powerful heater or multiple units. Be sure to choose a heater with a high AFUE (Annual Fuel Utilization Efficiency) rating, which indicates its efficiency in converting propane to heat. Look for heaters with an AFUE rating of 90% or higher to minimize energy waste and maximize your propane supply.
Find more answers
Browse the full Q&A library by topic, or jump back to the topic this question belongs to.