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BEopt Optimization Running Super Slowly

asked 2019-02-28 11:51:11 -0500

Alisa gravatar image

updated 2019-03-02 12:52:24 -0500

Hello,

I am running a BEopt model on a remote server that I built for it to run quickly. The remote server has 8 VCPUS and 32 GB of memory and the CPU is running at 100%, yet the model hasn't even completed one iteration in 24 hours. Is there something I'm missing to make this run faster? At this speed, it would take over a month for the optimization to complete. Normally my multifamily models take a while, but not more than 10 days and with this high powered machine I would have anticipated it would be done after 4 days or less. I attached the model in question.

Thank You! Alisa

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Do you happen to be modeling one stratified water heater per unit?

mdahlhausen gravatar image mdahlhausen  ( 2019-02-28 12:37:40 -0500 )edit

Yes it is using the heat pump water heater option which includes a stratified tank. Unfortunately since tank stratification isn't something we can change within BEopt I'm not sure how to resolve this.

Alisa gravatar image Alisa  ( 2019-02-28 12:57:19 -0500 )edit

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answered 2019-02-28 13:05:06 -0500

We are actively working on improving HPWH stratified tank runtime.

In the meantime, I would recommend running the optimization with an electric resistance water heater and then running a parametric to add in a HPWH to the point(s) of interest.

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You can follow the progress of this work at https://github.com/NREL/EnergyPlus/pu.... We expect this improvement to make it into EnergyPlus 9.1.0.

shorowit gravatar image shorowit  ( 2019-02-28 20:02:58 -0500 )edit

Thanks. I updated the model with this in mind, but am still having the same issue. My model has been running for 21 hours and is still on iteration 1 run 8. Is there something else that could be making it especially slow?

Alisa gravatar image Alisa  ( 2019-03-01 10:21:50 -0500 )edit

@Alisa, multifamily models with many units, smaller than normal timesteps (e.g., to support PCM analysis), and optimizations with many options selected could all be causing longer optimization times.

Eric Wilson gravatar image Eric Wilson  ( 2019-03-01 10:32:58 -0500 )edit

I am already using 60 min timesteps to avoid this and it has been stuck on iteration 1 run 8 for 20 hours without making any progress (it did iteration 1 run 1-7 in the first hour). Is there any chance it's doing a calculation for this long? Seems unlikely, but I don't want to stop the run if that is the case and lose the 21 hours of work.

Alisa gravatar image Alisa  ( 2019-03-01 10:38:13 -0500 )edit

Will we ever get to see the benefits of these improvements? BEopt is currently stuck at EnergyPlus 8.8

jpierce gravatar image jpierce  ( 2021-01-26 17:11:16 -0500 )edit

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Asked: 2019-02-28 11:51:11 -0500

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Last updated: Feb 28 '19