[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
RE: [EnergyPlus_Support] Running E+ on the "cloud"
Hmm... this is an interesting research question: in what situations 4 design days will be as good as an annual simulation. Someone must have investigated this!
About cloud for building simulation, I guess we are all excited by the possibilities... whether or not it is free is less relevant, I think. On a philosophical note, NOTHING is free as you said. E+ is free for user, yes, but who pays E+'s development? The US government. Where does US government give money from? Businesses and tax payers. Where do businesses and tax payers get money from? Their economic activities, part of which is enabled by E+. A consultant used E+ to do a project. Part of his fees will find its way back to the E+ team, eventually. At least he didn't have to pay upfront for E+, which reduces his risk, apparently. However, if he can be assured that by adopting a technology, it can increase his income more than the price he has to pay, he will be happy to do that.
There really isn't any fundamental difference between free and not free; it only slightly alters the distribution of 'money' between all players. The consultant kept more of his fees because he didn't have to pay for E+; so he got a bit wealthier. How does he use his new acquainted wealth? Spend it or invested it; either way put it back to economic activities. From the government's point of view, there is no difference between collecting tax from the E+ team, or paying them to do research and then collecting tax from everyone else who 'benefited' from the technology.
That was only talking about money. Now let's look at what is the essence of economic activities. In the current social and economic structure of the world, economic activities means only one thing: throughput of natural resources! Everything (economic activities) we do costs the Planet. Yes we can say that we are trying to improve the efficiency of this throughput, i.e. to power more economy by consuming same or less resources. It is not happening, yet; and there isn't any evidence that it ever going to happen. (There are quite a few books discussing this.) Our research and development is still supported by carbon-rich money. The only hope is, it is all for the greater good...
Coming back to cloud for building simulation, we engineers are naturally attracted to new technologies, just like the Apple cult's obsession to new iStuff. It is kind of like consumerism in an engineer's way... But, come on, we got to try cloud! It IS so cool!
Merry Christmas, everyone!
Yi
Dr Yi Zhang
IESD, De Montfort University, United Kingdom
________________________________
From: EnergyPlus_Support@xxxxxxxxxxxxxxx on behalf of YuanLu Li
Sent: Fri 23/12/2011 13:28
To: EnergyPlus_Support
Subject: RE: [EnergyPlus_Support] Running E+ on the "cloud"
All I was pointing out was that the current "Cloud" is simply a name change to make money.
All the Apps on the iPhone, etc. Are they better than what you can do on a PC?
In this world, nothing is free. The cost of running PC on Internet has not come down. It seems to be coming down because the usage limit has increased. The basic rate is still increasing.
The search engines are now showing more ads. to shield the real information, so that a user will see the ads.. The time needed to find what I want has increased. This is the real cost.
=====================================
I do not carry out annual simulation on EPlus. Therefore I do not need distributed computation.
I used the four season four day DesignDay simulation for most of my work. If a building does not use much energy for those four days and is comfortabale, it will be comfortable for the whole year.
=================================
Large shopping centre, hospital, Hotel, airport, railway stations have special need in HVAC. The designer for these have sufficient resources and do not need to use the public Cloud. They will have their private Cloud with distributed processing, but not free for public users.
===============================
I am really worried for our next generation. Thay may be deaf (iPod) and dumb (iPad) and communicate with one another by finger pointing throgh a Cloud (Face book, etc.).
ttyl.
Dr. Li
________________________________
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
From: yizhang@xxxxxxxxx
Date: Fri, 23 Dec 2011 11:08:35 +0000
Subject: RE: [EnergyPlus_Support] Running E+ on the "cloud"
Or to rewrite the E+ core and all component models, using OpenMP ;-)
This is not impossible. I bet there are tools that help you identify parallelizable code blocks. But, how many people out there thinking a single run of E+ is too long, if they are not trying to repeatedly run the same model? My guess at the moment is, a GUI that can adapt a parallel workflow to a 'slow' engine is more practical than to speed up the engine...
Yi
Dr Yi Zhang
IESD, De Montfort University, United Kingdom
________________________________
From: EnergyPlus_Support@xxxxxxxxxxxxxxx on behalf of Marcus
Sent: Fri 23/12/2011 10:11
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Subject: Re: [EnergyPlus_Support] Running E+ on the "cloud"
Lot's of great discussion points about one of my favorite topics, here are my two cents,
Dr. Li; I have to take a contrary opinion here and bet that internet capacity in the aggregate will fall in price and both bandwidth, processing, and storage will become more accessible in the near and long term future. But even if we are headed to a change in the market, I am still willing to pay good money for a cloud based simulation service, if it means, such as in Jim's case, that we can reduce from 16 hours (2 hours per run over ~8 ASHRAE 90.1 runs) for multi-use LEED certified facility, to something around a lunch or coffee break. I believe this is possible with the hardware sitting 95% idle in most consultancy offices, or with fee based cloud computing like EC2.
One challenge is how to parallelize the problem. We can already parallelize the discrete simulation runs. I've heard this called "embarrassingly parallel". This is done by the "multiple simulation" tab in EnergyPlus, and also done independently many times over for building simulation and other engineering domains. This would break up Jim's 16 hour problem down to 2 hours if you had 8 cores. And this works great for global search meta heuristics like evolutionary algorithms if your runs are small and population size can be large. But to get below 2 the two hours barrier requires significantly more effort. I see three strategies;
1. Underlying simulation kernel can run naturally in parallel (domain decomposition?)
- This would be true parallelization, where the solution of the underlying equations and algorithms is distributable, i.e. Matlab parallel for loop.
- Or individual EnergyPlus simulation modules are running in parallel?
- Is this really possible for a building simulation?
2a. Break up individual run, functional decomposition
- Jim has proposed breaking the building apart into sub-geometry/systems.
- I see this as fine for some cases, but generally speaking it has two challenges; one is simply knowing how to break it apart (time cost of expert user intervention), and two is that a building is inherently tightly coupled leading to high bandwidth between sub problems or loss of accuracy (paraphrasing Building Sim. Augenbroe 2001)
2b. Break up individual run, temporal decomposition
- For an annual simulation, break up into i.e. 12 months over 12 processors, and stitch them back together at the end, as in (Garg 2011) that Yi Zhang kindly pointed out.
3. Other problem decomposition approaches?
Sounds like a project for 2012!
Cheers and happy holidays,
Marcus
--
Marcus Jones, M.Sc., LEED®AP BD+C
http://www.optimalenergetics.com/
Freelance energy consultant
Vienna, Austria
On Thu, Dec 22, 2011 at 11:03 PM, YuanLu Li <yli006@xxxxxxxxxxx> wrote:
Running EPlus in the "Cloud" with distributed computing is definitely possible, if you are going to pay for the usage of the cloud service. EPlus is already in a private Cloud by running the on line simulation program.
I do not think any "Cloud" server or provider would let you run your own program with multiple users free of charge, or with the current Internet connection charge and without additional network access control.
We are running on the left over cream of the Y2K bubble. Very soon the Internet capacity will not be free any more. VOIP, Face book, U-tube, etc. will not be free any more.
I paid C$8.00 for 1GB of excess usage last month. It was because I had to accept free Microsoft up-date for Windows7, SP1, SP2 and all the .net, Office, Visual Studio, etc. When a large project is run in the Cloud, the connection cost would go up. The CD that is sold at a shop is just for the registration and the base software. It is not up-to-date.
I cannot imagine that the Cloud providers would allow users to tap the Cloud CPU power for distributed computing without paying a fee. If it is on "when availaable" basis, then it may take un-known time to complete a job.
I am already getting "loading" "sorry the service is not available" warnings on Hotmail on regular intervals. Please pay $29.99 annual fee, if you would prefer faster service and no commercials to cover the displayed message. There is large overhead control loaded with every Hotmail message.
This is the reason why I was commenting that the public free Cloud computing may not be that wonderful for real production computing. Organisation whould build their own Cloud for their users by re-organizing and improving their current private LAN.
Apps for Banking, looking up Chinese food, socializing, are not really "must have" services in the Cloud. When the cloud is not there, you can always pick up a phone. This is also the reason I do not want to give up by land line phone connection for the "home phone". When the unitility service is down, or the internet is down, the home phone is also not available.
There are now public Cloud, private Cloud, etc. I think, the availability of Cloud computing and what is a Cloud are still very cloudy.
==========================
"developing an energy optimization design tool by combining optimization algorithms with energyplus."
This is great in principle. However, for real grobal energy saving design in buildings or other equipment, it is not a mathematical computational problem. It is an engineering and cultural problem.
Dr. Li
________________________________
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
From: santiagogvelez@xxxxxxxxx
Date: Thu, 22 Dec 2011 16:59:33 -0300
Subject: Re: [EnergyPlus_Support] Running E+ on the "cloud"
Daniel, I'm definitely interested in hearing about your experience with EC2. I'm currently doing my thesis on developing an energy optimization design tool by combining optimization algorithms with energyplus. Given the number of simulation required I'm guessing cloud computing would be the only way to make it practical for commercial use. Im still on reaserch stage though, so not sure how plausible this is.
Best,
Santiago.
2011/12/22 Daniel Bergey <daniel@xxxxxxxxxxxxxxxxxxx>
Yesterday I created an EC2 account, installed Energy+, and ran a couple
of the packaged examples on a cloud machine. It took about an hour all
told to get started, mostly reading docs. I'd be happy to help if you
go this route.
This seems good for small numbers of sims. For big search problems,
next steps might be:
* package a disk image that has suitable software installed
* set up a work item queue, so that each computer automatically pulls
the next sim from the queue
* put postprocessing on the cloud machine to reduce bandwidth costs
Anyone interested?
Daniel
On Thu, 22 Dec 2011 09:17:28 -0500, "Jim Dirkes" <jim@xxxxxxxxxxxxxxxxxxxxxxxxxxx <mailto:jim%40buildingperformanceteam.com> > wrote:
> Dear Marcus,
>
> Keeping in mind that this is somewhat hypothetical at the moment.
>
> It's my understanding that E+ spends the most time figuring out the energy
> balance of all the mass in the building. Additional time, although of a
> smaller magnitude, is spent on HVAC energy balances and report variables.
> That said, I am imagining:
>
> . A multi-use facility (i.e., many different occupancy types and
> HVAC systems)
>
> . In a roughly 300,000 m2 (3,200,000 ft2) facility
>
> . Which wants to attain LEED certification
>
>
>
> I anticipate no difficulty creating HVAC systems since my past experience
> covers most or all of the systems, but the sheer size suggests that there
> will be a LOT of run time, even on a fast PC. My strategy will be to
> prepare small portions of the building and its HVAC individually, test them
> and make sure unmet load hours are acceptable. After the smaller portions
> are complete, I'll join them together for a complete building simulation and
> the various rotations.
>
> In this scenario, I should be able to keep several building portions
> underway simultaneously if I am using multiple PCs or the cloud equivalent.
> Up until this point I have been focusing on making the energy modeling
> process more effective, accurate and fast. Because I don't run full year
> simulations until the end of the process, I've been tolerating long run
> times. Now I want to take (or at least evaluate) the next step in making
> the whole process go faster.
>
> I just finished a small multi-use facility (~10,000 m2) which required 2
> hours for a complete run on a PC with reasonable speed (i5 CPU, 6GB RAM and
> solid state hard drive) - too long!
>
> At this point I think that not too many of the people who participate on
> this forum are worried about this, but I know some of you have addressed the
> issue and appreciate the feedback I've received.
>
>
>
> The Building Performance Team
> James V. Dirkes II, P.E., BEMP , LEED AP
> 1631 Acacia Drive NW
> Grand Rapids, MI 49504
> 616 450 8653
>
>
>
> From: EnergyPlus_Support@xxxxxxxxxxxxxxx <mailto:EnergyPlus_Support%40yahoogroups.com>
> [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx <mailto:EnergyPlus_Support%40yahoogroups.com> ] On Behalf Of Marcus
> Sent: Thursday, December 22, 2011 4:15 AM
> To: EnergyPlus_Support@xxxxxxxxxxxxxxx <mailto:EnergyPlus_Support%40yahoogroups.com>
> Subject: RE: [EnergyPlus_Support] Running E+ on the "cloud"
>
>
>
>
>
> Dear Jim,
>
> What type of application are you interested in when you say "large project"?
>
>
> If you are describing a single large ASHRAE 90.1 model that may take over 15
> minutes to run, I often simply use the "group of input files" tab to execute
> my approx. 8 models (i.e. 4 baseline and 4 proposed with different
> oversizing in the HVAC) using my 4 processor cores simultaneously, so it
> takes 30 minutes instead of 2 hours. And if you do this often, it might make
> sense to buy a new dedicated multicore core machine that you can use to
> execute jobs, and access the files over a network. I would recommend this
> approach just because it requires no extra software or setup.
>
> If however you are doing global optimization or parametric studies with
> HUNDREDS of executions, then you will likely need the approach that Dr.
> Crawley or Dr. Li have mentioned, and invest into grid/cluster/cloud
> computing. Fortunately, this is a problem that has been solved many times
> over in the IT world and there are many approaches and platforms available,
> the problem really is choosing one.
>
> (Aside: This is all a topic near and dear to my PhD and professional
> objectives, so if anyone wants to submit a paper or research project let me
> know!)
>
> Cheers,
>
> Marcus
> --
> Marcus Jones, M.Sc., LEEDRAP BD+C
> http://www.optimalenergetics.com/
> Freelance energy consultant
> Vienna, Austria
>
>
>
Non-text part: text/html
------------------------------------
Primary EnergyPlus support is found at:
http://energyplus.helpserve.com or send a message to energyplus-support@xxxxxxxx
The primary EnergyPlus web site is found at:
http://www.energyplus.gov
The group web site is:
http://groups.yahoo.com/group/EnergyPlus_Support/
Attachments are currently allowed but be mindful that not everyone has a high speed connection. Limit attachments to small files.
EnergyPlus Documentation is searchable. Open EPlusMainMenu.pdf under the Documentation link and press the "search" button.
Yahoo! Groups Links
<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/EnergyPlus_Support/
<*> Your email settings:
Individual Email | Traditional
<*> To change settings online go to:
http://groups.yahoo.com/group/EnergyPlus_Support/join
(Yahoo! ID required)
<*> To change settings via email:
EnergyPlus_Support-digest@xxxxxxxxxxxxxxx
EnergyPlus_Support-fullfeatured@xxxxxxxxxxxxxxx
<*> To unsubscribe from this group, send an email to:
EnergyPlus_Support-unsubscribe@xxxxxxxxxxxxxxx
<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/
Attachment not found:
d:\eudora\attach\winmail1.dat