Gap analysis between predicted energy from HB and measured energy from ASHRAE (US) and TM54 (UK)

Hi everyone,

Have you ever measured the performance gap between the predicted energy consumption deriving from an energy modelling simulation in HB and the measure energy from ASHRAE?
If yes, on average, how much is the gap?

For those who have worked on UK projects, what would be the gap if comparing the predicted energy consumption obtained from OpenStudio with the actual energy performance of the building as result of TM54?

Thank you

All of the default programs (loads and schedules) that come installed with honeybee legacy are taken from ASHRAE 90.1-2010. So those should be perfectly aligned and, in the next version of honeybee[+] that we are going to release soon, you will be able to select which version of ASHRAE-90.1 you are using as a base for all of these programs.

The default constructions in honeybee-legacy are not related to any building code or climate zone so it’s currently up to users to override these constructions with ones that are in-line with the building code they are using. In honeybee[+], we will have a library of templates for “Construction Sets” that can be applied to honeybee zones and assign all of the constructions that are needed to be compliant with a given version of ASHRAE-90.1 in a particular climate zone.

The detailed HVAC templates in honeybee-legacy are really generic and I will admit that they can deviate pretty far from ASHRAE in certain situations. So the best strategy here if you need to build a fully code-compliant detailed HVAC system would be to use IronBug to set the efficiencies on individual pieces of HVAC equipment. In honeybee[+], we will use routines that the OpenStudio team has developed to automatically set the efficiencies of HVAC equipment in compliance with a given version of ASHRAE. Of course, none of this last part matters if you are just simulating Ideal Air or simulating a passive building.

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