Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question

Size report units kBtu/h should be MBH

asked 2022-05-02 16:39:17 -0500

TheEnergyTutor's avatar

updated 2022-05-02 19:01:42 -0500

image description

The units in the open studio report are kBtu/h - but the official units should be MBH.

"k" is a metric abbreviation. It is not used in IP units. It's just wrong regardless of what people think makes sense. Here are some examples of what people in industry do. Both engineers and manufacturers.

image description

image description

Can this get corrected?

edit retag flag offensive close merge delete



You have brought this up before. I still disagree.

shorowit's avatar shorowit  ( 2022-05-02 21:23:37 -0500 )edit

And what about kBtu/ft2? It's the standard unit for EUI mixing an SI prefix with an IP unit.

MatthewSteen's avatar MatthewSteen  ( 2022-05-04 12:52:32 -0500 )edit

4 Answers

Sort by ยป oldest newest most voted

answered 2022-05-02 18:21:53 -0500

The 90.1-2016 and 90.1-2019 IP version section 6.8.1 Tables that list HVAC equipment efficiencies are in units of tons and Btu/h. kBtu/h seems like the clearer option here rather than using roman numerals.

edit flag offensive delete link more


I uploaded some more examples of what is used in industry. kBtu may "make sense" but it's not used and it's not actually a unit.

TheEnergyTutor's avatar TheEnergyTutor  ( 2022-05-02 19:02:56 -0500 )edit

answered 2022-05-04 07:33:49 -0500

TNZ Energy's avatar

Per "The unit Mbtu is used in natural gas and other industries to indicate 1,000 BTUs. However, there is an ambiguity in that the metric system (SI) uses the prefix "M" to indicate one million (1,000,000). Even so, "MMbtu" is often used to indicate one million BTUs particularly in the oil and gas industry. Energy analysts accustomed to the metric "k" for 1,000 are more likely to use MBtu to represent one million, especially in documents where M represents one million in other energy or cost units, such as MW, MWh and $." I am a die hard user of 'k' for thousands regardless of what comes after it.

edit flag offensive delete link more


If you are an "energy analyst" and don't know what MBH is you need to get fired.

TheEnergyTutor's avatar TheEnergyTutor  ( 2022-05-09 10:43:07 -0500 )edit

@TheEnergyTutor coming to a Q&A site asking for help and then insulting someone who tries to help is not a good way to receive help in the future.

MatthewSteen's avatar MatthewSteen  ( 2022-05-25 13:19:50 -0500 )edit

answered 2022-05-06 18:46:13 -0500

people in industry do. Both engineers and manufacturers.

The US is not the entire industry. Having worked abroad, I can confirm MBH is often confused for million BTU/h, whereas no one is ever confused by kBtuh (or kBtu/h). BEM software is used internationally, and should be designed to limit confusion.

edit flag offensive delete link more


A lot of amateurs get confused but that's not our problem. What country uses BTUs that doesn't know what MBH is?

TheEnergyTutor's avatar TheEnergyTutor  ( 2022-05-09 10:41:44 -0500 )edit

Countries that primarily use SI units, but do some work in the US and are forced to use IP occasionally. Canada is where I experienced this.

ericmartinpe's avatar ericmartinpe  ( 2022-05-09 11:10:20 -0500 )edit

answered 2022-05-23 12:59:08 -0500

TheEnergyTutor's avatar

The all mighty google has spoken. Check for yourself. None of the other comments in this thread provide any references. Only unsubstantiated personal opinions. image description

edit flag offensive delete link more

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Training Workshops

Question Tools

1 follower


Asked: 2022-05-02 16:39:17 -0500

Seen: 274 times

Last updated: May 23