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I wanted to compare FPS plots against
radiation plots so I could learn more about their correlation (or lack
thereof) in different locales. I planned to use one or the other to
help me get a sense for possible regional variation in daylighting/dimming
controls savings potential. I had a lot easier time finding radiation
data, if it is any consolation to you in your mission, Chip. but I
thought sunshine data would be better to use if available. Tabular
data is better for quantitative analysis of course, but I wanted to
see pictures.
FYI two good sources for solar radiation plots
are:
for an
annual plot (attractive training illustration),
for
monthly plots by various orientations ( a better analytical tool).
Not to be too contrary but I spot-checked the
tabular data from the source in my original email with the homepower map above
and the general patterns do seem to correlate pretty well.
Finally, for those of you that are interested, Jeff
Haberl responded to me directly with a FPS resource: "I believe that there is a map on Kreith
and Kreider's Solar energy handbook...that shows this for the world...using the
Angstrom-Lof minutes of sunshine." Thanks to
Jeff.
----- Original Message -----
From: Chip
Barnaby
To: Jon Maxwell
Sent: Wednesday, September 26, 2001 9:12 AM
Subject: Re: [BLDG-SIM] Fraction of Possible Sunshine I don't know of a source for a map, but I do have a question ... what do you want it for? I am trying to learn how people use this statistic. It has been traditionally observed, so people keep observing it. I am involved in work on ASHRAE TC 4.2 (Weather Information) that is developing methods for extracting solar radiation from weather data measured by ASOS (Automated Surface Observation System) now used to observe weather at most sites in the US. ASOS has planned to add sunshine meters to their machines (that plan is now delayed due to funding), but it would be just about as easy, and much more useful (in our opinion) to measure solar radiation. Sunshine fraction is a notoriously bad predictor of solar radiation (the correlations are pretty poor). With trivial data processing, minute-by-minute solar radiation data can be used to estimate sunshine, but not vice-versa. Thus as far as I know the solar and building simulation community has no use for sunshine data -- the statistic should be declared obsolete from our point of view. However, at every opportunity, I try to find why people want it, there may be some other uses that we don't know about. So, if you're willing, please let me know what you're up to. To the rest of BLDG-SIM: anyone else know of uses for sunshine fraction? Thanks, Chip Barnaby Does anyone out there have or know of a source for a graphical illustration of Fraction of Possible Sunshine over the U.S. I found a very good table of such data at http://cdiac.esd.ornl.gov/ftp/ndp021/ (file #12), but haven't had any luck with a map. Thanks in advance. Chip Barnaby cbarnaby@xxxxxxxxxxxxxx Vice President of Research Wrightsoft Corp. 781-862-8719 x118 voice 394 Lowell St, Suite 12 781-861-2058 fax Lexington, MA 02420 www.wrightsoft.com --------------------------------------------------------- =====================================================You received this e-mail because you are subscribed to the BLDG-SIM@xxxxxxxx mailing list. To unsubscribe from this mailing list send a blank message to BLDG-SIM-UNSUBSCRIBE@xxxxxxxx |