Jeremiah,
I 've checked. There were no differences in the output variables
and formats between the 7.0 and 7.1 IDFs (see attached). In fact,
if you ignore the comments, there are literally just a handful of
differences, all in the design day inputs.
Multi-threading helps if you're just doing one run at a time,
because you're utilizing other processors that might otherwise be
idle. However, when you have a large set of runs, you don't get
any advantage, because what's typically done is to run processes on
each core at the same time. For example, a couple of weeks ago I
created a "largish" data base of 12,000 DOE-2 runs for the energy
saving potentials of awnings and shade screens in 50 US cities.
Since I have a 4-core machine, I just gave each core a quarter of
the runs to do. The whole thing took about an hour.
Joe
Joe Huang
White Box Technologies, Inc.
346 Rheem Blvd., Suite 108D
Moraga CA 94556
yjhuang@xxxxxxxxxxxxxxxxxxxxxxxx
www.whiteboxtechnologies.com
(o) (925)388-0265
(c) (510)928-2683
"building energy simulations at your fingertips"
On 6/7/2012 1:46 PM, CleanTech Analytics wrote:
Joe,
I think I remember changing some output variables and
formats, possibly the issue for Energy Plus 7 was the problem?
The latest version of Energy Plus uses OpenMP
processing, to use it you choose number of threads
dependent on:
- How many processors are available on the system.
- If <= 30 nominal surfaces, arbitrarily setting the
number of threads to 1.
- For more surfaces add more threads,
The feature when used correctly saves computational time-
for large files with many surfaces by using more
threads. The issue is that for a large file with lots of
surfaces using one thread takes more time, or if you are
doing parallel processing you have to be careful not to
stack to many
parallel runs on top of threads or the
excessive computer memory space slows down the run.
Glad your up and running with your file and best regards-
There should also be a non-threded version in
your a folder. I use the non-threded version for
jE+ becuse it uses parallel processing, also when
runing multaple files from EP Launch
it may be better to run the non-threded version.
Jeremiah D. Crossett
CleanTech Analytics
503-688-8951
This document may contain valuable information
proprietary to CleanTech Analytics which is private
and confidential. It may not be shared, copied, stored
or transmitted in any form without the prior written
consent of CleanTech Analytics
On Thu, Jun 7, 2012 at 1:27 PM, Joe Huang <yjhuang@xxxxxxxxxxxxxxxxxxxxxxxx>
wrote:
First, I'd like to thank Jeremiah, Justin, and Dru for
bothering to look into this problem, and those others
who've given me their best wishes.
Although the inquisitive side of me wanted to know what I
was doing wrong, I finally took up Jeremiah's suggestion
and upgraded to Version 7.1, and the problem went away,
i.e., I'm now getting cooling electricity for the exact
same file, upgraded from Version 7.0 to Version 7.1. I've
also gone back and ran the original Version 1.4 IDF
straight from doe2ep, and there too the
Cooling Electricity reported normally.
So, I'm chalking this up to some bug in the reporting
routines in Version 7.0. I am quite surprised that nobody
else has reported this major problem earlier; isn't the
cooling electricity consumption one of the most important
variables in a building energy simulation ?
Attached are the multiple IDFs and * .mtr
from Versions 1.4, 7.0, and 7.1, in case anyone wants to
do some forensics on this glitch.
As a sidelight, I also recorded the run times between the
3 versions. EnergyPlus seems to have sped
up by a third from V1.4 to V7.0, but then slowed back down
in V7.1. I thought there was an effort to make EnergyPlus
run faster the past 3-4 years.
Version 1.4 132.8 seconds
Version 7.0 90.3 seconds
Version 7.1 145.5 seconds
Just as a contrast, DOE-2.2 took 66.0 seconds to do the
entire set of 33 runs, or 2.0 seconds per run.
On 5/31/2012 10:33 PM, CleanTech Analytics wrote:
Joe,
I made some small changes to your file, ran it
and found cooling energy use, see attached and
below.
Let me know if you have any questions and best
regards-
Source Energy End Use Components Summary
|
Source Electricity [kWh] |
Source Natural Gas [kWh] |
Source Other Fuel [kWh] |
Source District Cooling
[kWh] |
Source District Heating
[kWh] |
Heating |
32441.55 |
0.00 |
0.00 |
0.00 |
0.00 |
Cooling |
804178.78 |
0.00 |
0.00 |
0.00 |
0.00 |
Interior Lighting |
2491523.65 |
0.00 |
0.00 |
0.00 |
0.00 |
Exterior Lighting |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
Interior Equipment |
1214184.16 |
0.00 |
0.00 |
0.00 |
0.00 |
Exterior Equipment |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
Fans |
361727.88 |
0.00 |
0.00 |
0.00 |
0.00 |
Pumps |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
Heat Rejection |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
Humidification |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
Heat Recovery |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
Water Systems |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
Refrigeration |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
Generators |
0.00 |
0.00 |
0.00 |
0.00 |
0.00 |
|
|
|
|
|
|
Total Source Energy End
Use Components |
4904056.01 |
0.00 |
0.00 |
0.00 |
0.00 |
Jeremiah D. Crossett
CleanTech Analytics
This document may contain valuable
information proprietary to CleanTech
Analytics which is private and
confidential. It may not be shared,
copied, stored or transmitted in any
form without the prior written consent
of CleanTech Analytics
On Wed, May 30, 2012 at 10:24 PM, Joe Huang <YJHuang@xxxxxxxxxxxxxxxxxxxxxxxx>
wrote:
I made a mistake in my last
posting. I had attached the DOE-2
packed weather file instead
of the EPW weather
file. However, the good news
is that file is quite
small. This time, I'm attaching the
correct EPW weather file along
with the IDF and CSV
output files, but zipped to reduce
the size of the file.
Joe
On 5/30/2012 10:11 PM, Joe Huang
wrote:
> I've created a set of idf
files for a set of large retail
models originally developed in
> DOE-2.2. The outputs show
plenty ofcooling going
on (Cooling Rate) , but no cooling
> electricity use.
I suspect the problem is a mismatch
in the output variables, but I
> can't find the
source of the problem. Any help
would be appreciated. Attached are
the
> IDF, weather file, and monthly
CSV output files.
>
> Joe
>
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