[Bldg-sim] Revised TMY3 Weather Files now available on the Web
Jason Glazer
jglazer at gard.com
Wed Feb 11 05:26:36 PST 2015
Nathan,
Looks like you have been thinking about a way to improve
Appendix G. Anyone can submit proposals to improve Appendix
G using the procedure described on:
https://ashrae.org/standards-research--technology/standards--guidelines/continuous-maintenance
If you do decide to submit a proposal, please think about
the proposed language carefully and the direct and indirect
implication of the proposed requirements.
Thanks
Jason
On 2/11/2015 12:51 AM, Nathan Kegel wrote:
>
> Hi Kapil,
>
> Several people have emailed me off the list to express a
> similar sentiment. I’ll let them remain anonymous unless
> they choose to chime in.
>
> Two parts to this email: further exploration of the
> problems in part 1 and some ideas for solutions in part 2.
>
> Part 1.
>
> I’ve presented on this topic at ASHRAE conferences as well
> as whenever I do a training on doing LEED or code
> compliance energy simulation. I’ve done my own
> sensitivity analysis of many of the free Minneapolis area
> climate files and found I can vary the EUI of an office
> building with a VAV system by 14% just by selecting a
> different climate file that’s 12 miles away. Even more
> interesting (at least to me) was that I could change which
> design decision was best by changing the climate file.
> For example, the MSP climate file resulted in glazing X
> being the lowest EUI while selecting the Eden Prairie file
> (12 miles away) resulted in glazing Y being the best.
> There’s no micro climates involved and both of these files
> “bin out” to CZ6. However, neither of them are
> particularly “representative”. Eden Prairie has -12 F
> hours in May while the MSP file has 92 F degree hours in
> April. A quick check of the historical records show that
> -12F has never happened in recorded history in May in the
> Minneapolis area. Anyone who lives in Minneapolis can
> tell you that 90+ in April isn’t common. Even 70+ in
> April isn’t that common. A quick check of the historical
> record shows one time in nearly 200 years of records where
> above 90 was recorded before April 15. The third file,
> Crystal, was documented as having sub-freezing temps in
> the summer months in my previous reply to this thread. So
> that’s not representative, either. If there were no other
> options (which there are), I’d go with MSP as the best of
> a bad hand of climate files.
>
> Appendix G only requires in G2.3 (90.1-2010): “The
> simulation program shall perform the simulation using
> hourly values of climatic data, such as temperature and
> humidity from representative climatic data, for the site
> in which the proposed design is to be located. For cities
> or urban regions with several climatic data entries, and
> for locations where weather data are not available, the
> designer shall select available weather data that best
> represent the climate at the construction site. The
> selected weather data shall be approved by the rating
> authority.”
>
> The way this is written, I can literally pick any weather
> file – even if it is known to be filled with errors – and
> use it for LEED compliance and/or code as long as its
> nearby my proposed building. It’s up to the rating
> authority to question it.
>
> I’ve gotten many LEED review and code review comments in
> doing simulation. I’ve never once been asked about the
> quality of the climate data that was used in the
> simulation. Yet it impacts everything in the simulation:
> envelope, equipment performance (as many equipment
> performance curves are dependent on ambient conditions),
> and glazing selection just to name a few.
>
> The mentality of “plug and chug”, or worse, not even
> bothering to know which climate file your simulation
> program is actually using when it spits out results, is a
> very dangerous game if you’re at all concerned about a
> reliable result – and by extension – providing your
> customers with sound recommendations on how to spend their
> money.
>
> While nothing is perfect, I’ve had good experiences with
> using www.weatheranalytics.com
> <http://www.weatheranalytics.com>as a source for both TMY
> and AMY files. If there’s a problem with a file they
> create, they’ve been really good about making it right
> quickly.
>
> Another big problem with the free TMY3 files is they
> aren’t very up to date (2005 was ten years ago). Which is
> another reason why I like weatheranalytics.com – I can get
> more up-to-date weather data to help make a more informed
> decision.
>
> Part 2.
>
> In my opinion, Appendix G needs a new section for
> compliance: Pre-simulation Climate Analysis (call it Table
> G3.09).
>
> 1.Perform analysis on at least 1 TMY and 3 AMY (within the
> last 10 years) climate files near your site. If three
> aren’t available, document where you looked and what
> process was done to select the climate file used in
> simulation. (Although with services like Weather Analytics
> now available, this shouldn’t really be a problem for
> pretty much any project anywhere). Submit plots of
> dry-bulb temperatures and provide a narrative describing
> the process used in selecting the climate file used in the
> simulation. Include metrics like climate zone, bin
> analysis, and numerical justifications as well as local
> knowledge from trusted data sets in either the public or
> private domain.
>
> 2.Document both the ASHRAE defined climate zone from
> 90.1/169 and perform your own BIN analysis in accordance
> with ASHRAE methodology for non-defined locations. Submit
> both the defined climate zone and the derived climate
> zone. If they are different, advise as to which climate
> zone is being used in the simulation for baseline building
> generation.
>
> ·Fun facts (using TMY3 data sets): Dallas is defined at CZ
> 3A, it bins out to 2A. Nashville is defined as CZ 4A, it
> bins out to 3A. Toronto is defined as 6A, it bins out to
> 4A. All these are listed in 90.1-2010 which is the
> referenced standard in LEED v4 as well as an approved
> compliance path in IECC 2012. This is another potential
> design quandary: to get code approval and/or LEED points,
> I use a defined list in a table. However, the building is
> being built and will never actually see the weather that
> was used to define the climate zone.
>
> Better yet – get rid of defined climate zones altogether
> when taking a performance path. Require professionals who
> do simulation to understand how to open and analyze a
> climate file and derive the climate zone. Require review
> of that process by the AHJ and agreement that the analysis
> is valid and the CZ selected makes sense for the project.
>
> <http://www.iesve.com/>
>
>
>
> *Nathan Kegel*
> *Business Development Manager*
>
>
>
> O:
>
>
>
> 763.276.9981
>
> M:
>
>
>
> 415.420.9314
>
> http://www.iesve.com <http://www.iesve.com/>
>
> Integrated Environmental Solutions Limited. Registered in
> Scotland No. SC151456
> Registered Office - Helix Building, West Of Scotland
> Science Park, Glasgow G20 0SP
>
> Email Disclaimer <http://www.iesve.com/disclaimer.html>
>
> *From:*Kapil Upadhyaya [mailto:KapilU at kirksey.com]
> *Sent:* Tuesday, February 10, 2015 5:59 PM
> *To:* Nathan Kegel; West, Scott P; 'RobertWichert';
> bldg-sim at lists.onebuilding.org
> *Subject:* RE: [Bldg-sim] Revised TMY3 Weather Files now
> available on the Web
>
> Nathan,
>
> After you pointed this out, we started exploring this
> issue and did find significant differences in current
> weather files and 30 year average/EPW files.
>
> As IBPSA members, we should take this issue up on a
> national level to come up with a resolution.
>
> Regards,
>
> *Kapil Upadhyaya, ASHRAE BEMP, LEED AP*
> Senior Associate
>
> *Kirksey* | Architecture
> 6909 Portwest Drive | Houston Texas 77024 |www.kirksey.com
> <http://www.kirksey.com>
> o 713 426 7508 | f 713 850 7308 |kapilu at kirksey.com
> <mailto:kapilu at kirksey.com>
>
> *From:*Nathan Kegel [mailto:nathan.kegel at iesve.com]
> *Sent:* Monday, February 09, 2015 10:37 PM
> *To:* West, Scott P; 'RobertWichert';
> bldg-sim at lists.onebuilding.org
> <mailto:bldg-sim at lists.onebuilding.org>
> *Subject:* Re: [Bldg-sim] Revised TMY3 Weather Files now
> available on the Web
>
> To add to the list of tools that already does this for you:
>
> IES VE does this for you in the Vista application.
> Whether you’ve run an annual simulation or not, you can
> plot multiple variables overlaid on one another:
>
> 3D graphs:
>
> “Heat Maps”:
>
> You can also create your own custom variables in the VE
> (so you could create an enthalpy variable from the other
> variables and plot it on a graph or export to a
> spreadsheet, etc.):
>
> This is a .EPW file format from:
> http://apps1.eere.energy.gov/buildings/energyplus/cfm/weather_data3.cfm/region=4_north_and_central_america_wmo_region_4/country=1_usa/cname=USA
>
> For those of you still tuned in – a bit of a digression:
>
> Note the values that are errors in June and August (the DB
> is well below freezing 10 F) – that’s never happened in
> the recorded history of the area – let alone in the
> timeframe that TMY3 files are comprised of). The coldest
> value EVER for the entire state in the month of August is
> 21 F. That occurred in Kelliher which is more than 200
> miles north of this location.
>
> I’d suggest opening any of the climate files you get and
> ensuring they aren’t full of invalid data points. I’ve
> found far too many of them to be too error-filled to be
> useful for simulation. Eden Prairie, MN (still spelled
> incorrectly on the DOE website – “Edin”) is also rife with
> sub-zero temperatures in May (also never happened in
> recorded history). The Portland, OR TMY3 has 114 F days
> in late October (ditto). I think you get the idea.
>
> <http://www.iesve.com/>
>
>
>
> *Nathan Kegel*
> *Business Development Manager*
>
>
>
> O:
>
>
>
> 763.276.9981
>
> M:
>
>
>
> 415.420.9314
>
> http://www.iesve.com <http://www.iesve.com/>
>
> Integrated Environmental Solutions Limited. Registered in
> Scotland No. SC151456
> Registered Office - Helix Building, West Of Scotland
> Science Park, Glasgow G20 0SP
>
> Email Disclaimer <http://www.iesve.com/disclaimer.html>
>
> *From:*Bldg-sim
> [mailto:bldg-sim-bounces at lists.onebuilding.org] *On Behalf
> Of *West, Scott P
> *Sent:* Monday, February 9, 2015 6:47 PM
> *To:* 'RobertWichert'; bldg-sim at lists.onebuilding.org
> <mailto:bldg-sim at lists.onebuilding.org>
> *Subject:* Re: [Bldg-sim] Revised TMY3 Weather Files now
> available on the Web
>
> Robert,
>
> Once you get two psychrometric data points of moist air,
> you should be able to derive the other properties that you
> desire. A lot of the hourly weather files just happen to
> provide humidity in DP. Obviously if you have more than a
> few data points to evaluate (like a full TMY3 file),
> looking them up on a psych chart isn’t very practical.
> Unless you’re particularly interested in evaluating
> partial pressure equations, I would recommend using
> readily available software as a data filtering tool. I
> recommend ClimateConsultant which is a free software
> produced by UCLA:
>
> http://www.energy-design-tools.aud.ucla.edu/climate-consultant/request-climate-consultant.php
>
> The software can be used for visualizing weather data and
> evaluating heating and cooling strategies. It’s great for
> that, but I often simply use it to filter raw weather
> files and then export to Excel. The whole process takes 5
> minutes once you have the software installed. You simply
> find the appropriate EPW weather file (EnergyPlus format)
> from the web (link provided in the software) and import it
> into ClimateConsultant. You can then export to csv. I
> like how the software will automatically convert from SI
> to IP units. You can choose other ways of representing
> humidity like RH and WB. You can also use it to quickly
> construct daily or monthly averages if desired.
>
> Anyway, that’s my plug for ClimateConsultant for those of
> us that can’t program good data filters (or are too
> lazy). I hope it’s helpful.
>
> Scott P. West, P.E., LEED AP BD+C, BEAP, BEMP | *JACOBS*|
> Mechanical Engineer | Energy & Power Solutions|
> 817.222.8512 office |817.897.1882 cell
> |scott.west at jacobs.com <mailto:scott.west at jacobs.com>|
> www.jacobs.com <http://www.jacobs.com/>|
> www.jacobs.com/energyportfolio
> <http://www.jacobs.com/energyportfolio>
>
> *From:*RobertWichert [mailto:robert at wichert.org]
> *Sent:* Monday, February 09, 2015 2:34 PM
> *To:* bldg-sim at lists.onebuilding.org
> <mailto:bldg-sim at lists.onebuilding.org>
> *Subject:* Re: [Bldg-sim] Revised TMY3 Weather Files now
> available on the Web
>
> These weather files are great, thanks for the info, but I
> am trying to get wet bulb temperature too, and they do not
> seem to give wet bulb temperatures.
>
> Any ideas on that, perhaps?
>
> --
> Robert P. Wichert P.Eng. LEED AP
> CEPE CEA HERS I/II BPI BA
> +1 916 966 9060
> FAX +1 916 966 9068
>
>
>
> ========================================
>
> On 1/30/2015 9:10 PM, Joe Huang wrote:
>
> White Box Technologies (WBT), in collaboration with
> the National Renewable Energy Laboratory (NREL), has
> revised the TMY3 weather files to correct
> inconsistencies in units for illuminances, improve the
> reporting of Liquid Precipitation, replace all missing
> records with interpolated or filled values (chiefly
> for visibility, ceiling height, aerosol optical depth,
> and albedo), and add a new variable for Present Weather.
>
> Since their release in 2005, the TMY3 weather files
> covering 1,020 locations in the US and dependencies
> has become the standard set of weather files for use
> in computer simulations of solar energy conversion
> systems and buildings. The intent of this revision is
> not to redo the fundamental analysis, but correct some
> known errors and make modest improvements in the
> reporting of subsidiary climate variables.
>
> The only impact from these corrections and changes are
> for daylighting simulations that use the illuminance
> values, and for building simulations that use the
> liquid precipitation to model green roofs or moisture
> transport through the building envelope. The added
> Present Weather variable is not directly used in any
> simulation program, but allows the DOE-2 BINM files to
> have correct IRAIN and ISNOW flags, although these two
> variables are not being used in DOE-2. Filling in
> missing data for Visibility, Ceiling Height, etc.,
> should have no impact on the use of the TMY3s, but
> improves their overall record-keeping.
>
> The revised TMY3 files in their native CSV format have
> been provided back to NREL and are available here:
> http://rredc.nrel.gov/solar/old_data/nsrdb/1991-2005/tmy3
>
> The revised TMY3 files in EPW and BINM formats are
> available for free download on the White Box
> Technologies web site at
> http://weather.whiteboxtechnologies.com/wd-TMY3 or by
> selecting File Type as "TMY3" at
> http:/weather.whiteboxtechnologies.com/search
> <http://weather.whiteboxtechnologies.com/search> to
> search using GoogleEarth. The zip file names are
> unchanged, but the underlying EPW and DDY files will
> have the *TYA designation to distinguish them from the
> previous TMY3 versions.
>
> For a more detailed description and full documentation
> of the revision, please see the attached memorandum.
>
> Joe
> --
> Joe Huang
> White Box Technologies, Inc.
> 346 Rheem Blvd., Suite 205A
> Moraga CA 94556
> yjhuang at whiteboxtechnologies.com
> <mailto:yjhuang at whiteboxtechnologies.com>
> http://weather.whiteboxtechnologies.com for
> simulation-ready weather data
> (o) (925)388-0265
> (c) (510)928-2683
> "building energy simulations at your fingertips"
>
> _______________________________________________
>
> Bldg-sim mailing list
>
> http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org
>
> To unsubscribe from this mailing list send a blank message toBLDG-SIM-UNSUBSCRIBE at ONEBUILDING.ORG <mailto:BLDG-SIM-UNSUBSCRIBE at ONEBUILDING.ORG>
>
> ------------------------------------------------------------
>
> NOTICE - This communication may contain confidential and
> privileged information that is for the sole use of the
> intended recipient. Any viewing, copying or distribution
> of, or reliance on this message by unintended recipients
> is strictly prohibited. If you have received this message
> in error, please notify us immediately by replying to the
> message and deleting it from your computer.
>
>
>
> _______________________________________________
> Bldg-sim mailing list
> http://lists.onebuilding.org/listinfo.cgi/bldg-sim-onebuilding.org
> To unsubscribe from this mailing list send a blank message to BLDG-SIM-UNSUBSCRIBE at ONEBUILDING.ORG
--
Jason Glazer, P.E., GARD Analytics, 90.1 ECB chair
Admin for onebuilding.org building performance mailing lists
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20150211/4a12e029/attachment.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 5346 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20150211/4a12e029/attachment.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 27827 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20150211/4a12e029/attachment.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 98277 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20150211/4a12e029/attachment-0001.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 83844 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20150211/4a12e029/attachment-0002.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 33351 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20150211/4a12e029/attachment-0003.jpeg>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 34947 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20150211/4a12e029/attachment-0001.png>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/png
Size: 34051 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20150211/4a12e029/attachment-0002.png>
More information about the Bldg-sim
mailing list