OK, British Thermal Units (BTUs) are in the news today as they are a measurement unit which people toss around to rate the potential energy of a energy source or imply the efficiency of particular machinery. Recently I saw a couple presentations of machinery which was “rated” for output of so many BTUs of space heat. While there are some units which have gone through certification types of processes which through lab tests can attest accurately to the amount of BTUs “put out”, many manufacturers make their own claims and often will also attach a subjective efficiency rating of what percentage of the potential BTUs in the fuel are actually delivered.
So, while some may have an EPA approval or UL approval, many manufacturers may be putting out numbers that come out of their own labs, done under their own procedures and data collection. This is tenuous. Worse, some vendors are making claims of the output being equal per BTUs to some dollar amount of fuel oil which from what I’ve seen involves a lot of hand waving and probably is not accurate. So, don’t ignore BTUs, but go to a reputable university or independent lab testing to try to get documented BTU and efficiency ratings of fuel and machinery output for figuring savings or fuel displacement amounts.