Weather files with predicted future data?

Hi Mark -  I've used this tool before:  http://www.energy.soton.ac.uk/ccworldweathergen/ It's a bit clunky, but allows you to morph any climate file for any location, as opposed to this fee-based data set: https://www.cibse.org/weatherdata Best of luck!

We’ve used Mark’s first tool in the past as well. There are some shortcomings to using it: (in the words of Chris Mackey – Payette Green Guru) “That excel tool is what I currently use to generate future weather and I was hoping that the authors would share their source code so we can broaden its use in Dragonfly. However, from their lack of response, it seems that none of the authors are interested in continuing the development of the tool or fixing some of the bugs we found in it. There’s also a general consensus among the experts that I have talked to that CCWeatherGen is not a very good way to account for climate change since it uses the IPCC’s old worst-case CO2 emissions scenarios and the whole process that the tool uses to morph epw files to account for climate change has a lot of issues. By “morphing,” I mean the tool is simply adding the temperature change to the existing EPW instead of generating a new EPW from statistical analysis of the existing EPW. So CCWeatherGen captures the average shift in temperature that can happen from climate change but does not accurately model the change in variations of future weather, which is arguably the thing that is going to change the most with global warming. All of this said, the CCWeatherGen the best method that has a “normal” interface so it’s better than nothing for now. Also, never purchase climate change files from http://www.weather-shift.com/ since their data really isn’t much better than that produced by CCWeatherGen.” Ale. Alejandra Menchaca, Ph.D., LEED AP, WELL AP Senior Associate Thornton Tomasetti 27 Wormwood Street, Suite 200 Boston, MA 02210-1668 T +1.617.250.4100 F +1.617.250.4110 D +1.617.250.4177 M +1.617.999.0274 AMenchaca@ThorntonTomasetti.com www.ThorntonTomasetti.com From: Shawn Hesse [mailto

Hi Mark, You can also use this tool. http://www.weather-shift.com/ http://www.iesve.com/support/weatherfiles/weathershift I usually prefer Shawn’s link though. -berardo F

This isn't about EPW files but a more user friendly resource for projections in US can be found on climate.tool.gov website here: https://toolkit.climate.gov/#climate-explorer zip code specific info for temperature, precipitation Also a new resource that's out in beta developed by folks from public and private sector together: PREPdata, an open source map-based platform with curated climate, physical and socioeconomic datasets. See: https://prepdata.org/ It looks pretty cool. I'd love feedback on these. MAL Mary Ann Lazarus maryannlazarus2@gmail.com mobile: 314.805.9332

http://www.weather-shift.com/ is a plug-in developed by Arup (with others?) to allow for future climate models to inform building energy models. If interested I can introduce you to Cole Roberts at ARUP who is working on this. Brad Jacobson Associate Principal d 415-321-6330 ehdd.

My 2 cents: There’s a few resources out there to look at future weather files. There was an interesting session the ASHRAE energy modeling conference a couple of years ago that was focused on weather – from TM7 files, AMY files and predictive files too. There was someone from Big ladder presenting their Elements tool as well (https://bigladdersoftware.com/projects/elements/) that allowed you to edit offset and normalize weather data. A big takeaway is that when you’re dealing with future weather, rather than using a single weather file, its more beneficial to run bracketed scenarios that give you a range of outcomes. From:

Vikram, Do you remember which SimBuild conference that was? Any chance you have access to the paper? It would be a great reference to have at hand. Thanks! Alejandra Menchaca, Ph.D., LEED AP, WELL AP Senior Associate Thornton Tomasetti 27 Wormwood Street, Suite 200 Boston, MA 02210-1668 T +1.617.250.4100 F +1.617.250.4110 D +1.617.250.4177 M +1.617.999.0274 AMenchaca@ThorntonTomasetti.com www.ThorntonTomasetti.com

Hah! Thank you, Ale, for posting my thoughts on the CCWeatherGen Tool.  It's good to know that my words live on :). I just wanted to reaffirm that I strongly advise against the ARUP WeatherShift tool.  While WeatherShift is using updated climate projections from the most recent IPCC reports (unlike CCWeatherGen which I think is using the 3rd assessment report date), the methodology is generally the same as CCWeatherGen.  In my opinion, you are throwing your money away if you go down this route as you might as well use CCWeatherGen. If you really need the most accurate depiction of future weather, the state of the are is this open source project that Parag Rastogi built for his PhD.  He has been updating it and I'd recommend contacting him if you actually plan on using it since getting it to run is very complex.  The last I talked to him, you still needed 10 TB of free space to hold the IPCC dataset while you run it so it's not for the faint of heart.  However, it does aim to capture both the average temperature shift and the change in weather variation with future climates. -Chris

Alejandra, It wasn’t Simbuild – it was an ASHRAE conference. I don’t think there was a white paper associated with the presentation. Here’s a link to the conference program. The session I was referring to was Seminar 5 on Page 6. -Vikram From: A

Thank you Chris and Alejandra for weighing in on what tool is really useful. I am looking into CCWeatherGen and am realizing that their workflow is really set-up for UK geographical area. Any comments on how one would use CCWeatherGen to generate future weather data for US cities with reasonable accuracy? 

Amir, We used the tool and CCWeatherGen Manual for guidance to convert US files with no issues. There are two different websites – one for UK and one for the rest of us. http://www.energy.soton.ac.uk/ccworldweathergen/ (non-UK) http://www.energy.soton.ac.uk/ccweathergen/ (UK) -Kjell F

We do the same. Margaret Montgomery, FAIA, LEED AP BD+C, WELL AP Principal NBBJ 223 Yale Avenue North SEATTLE WA 98109 Direct: 206.223.5230 Mobile: 206.200.4526 www.nbbj.com / @nbbjdesign / http://meanstheworld.co [cid:image003.png@01D3EE8B.D16DB890]

Thanks much Kjell, I hadn't realized there were two websites/tools! 

Could those that have used such climate/weather extrapolation tools share stories about how this information changed their design?   Easy example: When the peak design temperatures are higher, the cooling system will need more capacity--but this might be broken into two parts: The internal components (say, duct sizes if you are using an air-based system) might need to get larger now (because they'd be difficult to change out later), while the cooling plant might be designed to be expanded in a modular fashion later.   But I'd be curious to hear how others have accommodated greater variability in future weather (mentioned by Chris and Alejandra) in their designs.  Example: if one were trying to make a building that was truly off-grid for both energy and water, one could see how greater variability might affect the size of, say, water cisterns or onsite energy storage to be able to get through longer droughts or longer runs of cloudy days.  But just doubling capacity to ride out rare events can actually hurt how well the systems operate under normal conditions.  (For example, some battery systems lose capacity if they are not deeply cycled regularly.)  So: Please share stories!  Thanks in advance.

Very good questions Z. I can only nibble at the answer with our work to date. You bring up some great points that I’ll need bring up on our next projects. As a reference, the projects I’m talking about are in the Seattle region. I’ve attempted (with no luck) to get energy analysts to use a variety of AMY files to test building performance a variety of conditions, with the performance averaged or at least understood between the various real scenarios. Since AMYs can be much more recent than the data that has been incorporated into TMYs, this would account for recent historical weather patterns, but still not future patterns for energy estimates. We have tested many (now we test all) of our naturally ventilated projects where no mechanical cooling is provided with future weather files to see if they still meet comfort standards, and begin conversations with our clients about this. We have used 2050 and 2080 weather files using the middle ground in the future scenarios. I don’t believe this has changed our designs radically, though. Since many mechanical engineers double the size of the cooling plant from what is needed (they don’t get complaints for oversizing), presumably some future-proofing is generally designed in. We have had conversations about future weather, but I don’t believe we have suggested that a cooling plant be sized larger for future climate; it may be happening, though. One water example: we designed a water cistern to flush toilets year-round, but we used historical (1945-2005) data. While historically we have at least some rain every month of the year, It turns out that in 3 of the last 4 summers we have had at least one full month with no rain, meaning it is performing well 10-11 months of the year but not the full year. We were not attempting LBC or other certification for water. The other issue is that historically the average rainfall is in the mid 30 inches annually; many recent years have been in the mid 40s. So the IPCC predictions – more torrential rain in winter, less total rain in summer – are proving to be accurate. It’s a great subject and perhaps this group can come to some conclusions for best practices with using future weather/ -Kjell From: Z Smith [ma

Running the scenario in 2050 and 2080 can be fun, but impacting the design will need to match the time horizon and clients that believe those numbers. Regarding central HVAC equipment, typically they last 20 years or so, if the time horizon is 2050/2080, chances are those equipment will be replaced anyway.  Tenant ductwork usually will change less than that time horizon with commercial tenants.  The key here may be infrastructure - piping, cables etc., can last for 40+ years and more.  This time horizon requires a different outlook to accommodate a larger change.  Curtain wall can last 40+ years, that time horizon may also be different.  Most clients, from government to private developers, when they have to put money where their mouths are, have a hard time concluding the future scenario will be the way we modeled.  Even in electric vehicles, while GM CEO said GM will be all electric in the future, we are designing to at most 10% electric vehicles in many of our projects.

Hey friends, I'm looking into this topic and trying to steer a mechanical engineer, who has not run future climate scenarios before, towards a climate file they can use. This discussion is largely from 2018 and I'm wondering if there is any updated information. Is there a new source for future climate files, or are the sources referenced in this thread still the best available? Thanks!

Climate scientist Katharine Hayhoe (https://climate.leeds.ac.uk/events/forecasting-our-future-a-conversation-with-dr-katharine-hayhoe/) was the keynote speaker just this morning at AIA Grassroots, and she specifically referenced a program to provide publicly accessible predective weather files for all US weather stations, based on work she had been doing city-by-city to help with climate change planning.  She said it would be released 'soon,' presumably through Texas Tech where she teaches, but I couldn't find any info about it online. Maybe others in the group know more about it / timeline?

Hi Kristian, we use (https://www.weathershift.com) to develop alternate modeling scenarios that take into account global warming. You can download weather files by location with varying levels of temperature shift.

Kristian, As a mechanical engineer that has used future looking weather files, we use weathershift.com (as noted by others earlier in this thread).  There is a fee to purchase the weather file, though.  I'm interested if there are free options available now or soon, though. We recently conducted a future energy and load analysis for a project in Washington, DC using weathershift files, and found that the net effect of annual energy use was negligible in the RCP 8.5 and RCP 4.5 50% scenarios in 2040-2050 vs now (historical weather data) because the heating savings was offset by increased cooling energy use.  Projects in cooler climates would likely see energy savings (more heating savings than increased cooling energy use), whereas projects in warmer climates would likely see net annual energy increases (little heating energy savings, more extreme cooling). 

I'm interested in your valued opinion on the Federal and institutional tools like this one: https://climatetoolbox.org/tool/Future-Climate-Dashboard or https://toolkit.climate.gov/#climate-explorer These have been useful in my consulting work over the years but I'm not designing building envelopes or systems. thanks. MAL Mary Ann Lazarus maryannlazarus2@gmail.com mobile: 314.805.9332

I use weather files from: https://www.energyplus.net/weather

These are free and highly credible. https://slipstreaminc.org/tools/climate-data-toolkit Adam McMillen, PE, CPHC, LEED AP BD+C Director of Sustainability [IMEG Corp.] IMEG Corp. 1100 Warrenville Road | Suite 400W | Naperville, IL 60563 (630) 527-2320 | phone (312) 852-1360 | mobile (630) 527-2321 | fax Adam.M.McMillen@imegcorp.com website | my linkedin | vCard | map | regional news [Twitter][Facebook][LinkedIn] Learn more about us and the IMEG story! This email may contain confidential and/or private information. If you received this email in error please delete and notify sender.

Hi Mary Ann, I think these are great! I have not seen them before. The future wx files are great for modeling because you can stick them in the model and tell people you did it and here are the results. But this type of approach would help with communicating to a more diverse audience than just the A/Es. I could also see using them to test sensitivity of envelope to extremes we have seen in the past (and are more likely to come in the future). Something that will resonate more than some potential thing in the future that is much harder to grasp. I mean, just look at Houston [cid:image001.png@01D7069F.57283AE0] Thanks for sharing! Adam McMillen, PE, CPHC, LEED AP BD+C Director of Sustainability [IMEG Corp.] IMEG Corp. 1100 Warrenville Road | Suite 400W | Naperville, IL 60563 (630) 527-2320 | phone (312) 852-1360 | mobile (630) 527-2321 | fax Adam.M.McMillen@imegcorp.com website | my linkedin | vCard | map | regional news [Twitter][Facebook][LinkedIn] Learn more about us and the IMEG story! This email may contain confidential and/or private information. If you received this email in error please delete and notify sender.

Mark, I have been using this site: https://crt-climate-explorer.nemac.org/ I don't believe they have the *.epw files specifically - though I have found is the most compelling forecasting climate graphics for future emissions scenarios.    Steven Baumgartner BUSS | 917.664.8666