[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: [EnergyPlus_Support] Re: extreme weather data

I’m wondering how “extreme” you think weather might become.  I think long term climate change varies on the order of about plus / minus 1-2C, which doesn’t strike me as significant for system sizing or annual energy use….


James V Dirkes II, PE, BEMP, LEED AP
Energy Analysis, Commissioning & Training Services
1631 Acacia Drive, Grand Rapids, MI 49504 USA
616 450 8653


From: EnergyPlus_Support@xxxxxxxxxxxxxxx [mailto:EnergyPlus_Support@xxxxxxxxxxxxxxx] On Behalf Of Chuck Khuen
Sent: Sunday, August 11, 2013 2:50 PM
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Subject: Re: [EnergyPlus_Support] Re: extreme weather data



Well, we are looking into that too.  I think it would be good to have all forms available Typical, Extreme and Future Metoriological Years.



Weather Analytics


From: ooikoonbeng <ooi_kb3@xxxxxxxxxxx>
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Sent: Sunday, August 11, 2013 5:47 AM
Subject: [EnergyPlus_Support] Re: extreme weather data



Excuse me for putting a slight diversion on this subject of weather data.

Correct me if i am wrong, the EPW is typical year data, which is a compilation of typical months' data of the past 20-30 years historical records.

A not-so-far-fetched, apologies if it is overly ambitious, objective of simulation is to predict how much conditioning energy a building needs during the design or planning of retrofitting stage, i.e. before the building is built.

Would it not be fair then to have predicted weather data for the coming year/s? This could be based on some of the 'projections of global warming' by year.....

Just a passing thought
regards, ooi

--- In mailto:EnergyPlus_Support%40yahoogroups.com, Joe Huang <YJHuang@...> wrote:
> Hu Jia,
> Here's more information on the ASHRAE Research Project that might be of interest to you.
> It's RP-828 "Sequences of Extreme Temperature and Humidity for Design Calculation",
> principal investigator Don Colliver (former ASHRAE president (!)), 1997. The abstract
> follows:
> Specific values for the design temperature have long been used as a starting point for
> design and sizing calculations for many applications. Designs using these extreme one-hour
> values are appropriate if the time constant of the system being designed is short; however
> if the system being designed has a significant thermal lag the extreme single-hour value
> can be significantly inadequate. The purpose of this report is to document the development
> of a technique to select sequences of data from long-term weather records and then present
> the results of using this technique on long-term weather data from a number of locations
> in North America. A number of different methods of combining the multiple hours of data
> within a sequence to produce a single value which then could be ranked were tested. The
> method of taking the average of the parameter over the time window was selected as the
> best method. It was found that the non-steady-state heat transfer method could not be used
> as a reliable indicator of the extreme sequences because the specification of the wall
> type to be used introduced a large variation in the selection of the extreme sequences.
> The purpose of this project was to develop a technique to select sets of data from
> long-term weather records which could be used in designs needing weather data longer than
> one hour and then use this technique on long-term weather data from a number of locations
> in North America.
> You can get the technical report from the ASHRAE Web site (free for members), but when I
> tried the Web site said it couldn't find the PDF. If so, you could also try to contact
> Don himself colliver@...
> Joe (also JH!)
> Joe Huang
> White Box Technologies, Inc.
> 346 Rheem Blvd., Suite 108D
> Moraga CA 94556
> yjhuang@...
> http://weather.whiteboxtechnologies.com/ for simulation-ready weather data
> (o) (925)388-0265
> (c) (510)928-2683
> "building energy simulations at your fingertips"
> On 8/9/2013 4:12 PM, Joe Huang wrote:
> > Your best bet is the National Solar Radiation Data Base (NSRDB) from NREL that contains
> > the hourly weather data for 1,454 US locations from 1991 through 2010.
> > http://rredc.nrel.gov/solar/old_data/nsrdb/1991-2010/
> > That'll give you plenty of data to work with.
> >
> > What is your definition of extreme weather conditions? Are you looking for individual
> > hourly values, or actual weather sequences? If you're studying this with EnergyPlus (or
> > any simulation program), I would recommend the latter, since the building's response to
> > climatic conditions depends a great deal on the thermal history extending for up to
> > several days. 20% above normal sounds much too lax to me, since ASHRAE design conditions
> > are defined as 0.4%, 1%, and 2% for cooling and 99.6%, 99%, and 98% for heating.
> >
> > If you're working to select extreme temperature sequences, e.g., most extreme 3-day or
> > 5-day sequences, you might look at work done about 20 years ago by Don Colliver for
> > ASHRAE (don't remember the RP number or title), where he produced 5-day design sequences
> > for 230+ US locations based on the highest or lowest average daily temperatures,
> > selected using the same 0.4%, 1% criteria and method as used for the ASHRAE Design
> > Condition tables. I would think that updating that work using the NSRDB would get you
> > what you need, but you might want to modify the selection criteria.
> >
> > Joe
> >
> > Joe Huang
> > White Box Technologies, Inc.
> > 346 Rheem Blvd., Suite 108D
> > Moraga CA 94556
> > yjhuang@...
> > http://weather.whiteboxtechnologies.com/ for simulation-ready weather data
> > (o) (925)388-0265
> > (c) (510)928-2683
> > "building energy simulations at your fingertips"
> >
> > On 8/9/2013 7:40 AM, Jia Hu wrote:
> >>
> >> Hi all,
> >>
> >>
> >> I am studying the impact of extreme weather conditions using EPlus. I am trying to find
> >> the source years (e.g., 20 year data) to extract the extreme data for each day? Anyone
> >> has suggestion about how to get the extreme weather condition (e.g, 20% above normal)?
> >> Where can I find these source data. The location of my interest is in US.
> >>
> >> Thanks,
> >>
> >> JH
> >>


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:

The group web site is:

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.

Your email settings: Individual Email|Traditional
Change settings via the Web (Yahoo! ID required)
Change settings via email: Switch delivery to Daily Digest | Switch to Fully Featured
Visit Your Group | Yahoo! Groups Terms of Use | Unsubscribe