Dear Chris,
My normal modelling site is within 200 miles of home (Grand Rapids, MI) and I agree that "actual" solar data is hard to find.
2005 data is way too old in my opinion, for modeling an existing building. Building usage almost always is different that far in the past and can be a significant factor in energy use. I really want to match up the most recent usage patterns (as reflected in utility bills) and weather in one model.
I already subscribe to NNDC's data service, which is helpful. They do not report any solar information, however. NREL does have some data (with a lot of missing time periods for the closest station), but they have a cloud cover data field which I'm hoping may be useful. As mentioned in a post roughly a month ago, wunderground. com also has some good info.
I'm still hoping that someone has incorporated actual cloud cover data or an equivalent into an E+ weather file....
--- In EnergyPlus_Support@ yahoogroups. com, Chris <chris@...> wrote:
>
> "Actual" solar radiation data would mean they are recorded on site,
> which is a rare occurrence. However, if you mentioned the location of
> your project, it would be possible to determine the distance of the
> closest measurement station.
> If in the US and for data during 1998-2005, the NSRDB _modeled_ data
> could be used.
> For other situations, that kind of modeled data also exists, but you
> might have to get it from private companies and pay for the service.
>
> Chris
>
> > I'm busy trying to understand weather files well enough to create one that runs well in E+ and contains the ACTUAL weather for a period of interest (the
utility billing periods for the most recent ~12 months).
> >
> > Obtaining actual temperature and humidity data doesn't look too challenging, but solar data appears to be more complicated. Some of the weather data I have found includes an indicator for cloud cover, which seems to be the place to start, since the sun does the same thing every day above the clouds.
> >
> > Since the E+ weather documentation is hard to follow, I'm hoping that someone has recommendations for how to plug in cloud cover data so that E+ actually uses it properly. Guidance anyone?
> >
> > While I'm at it, are there other weather factors worth considering?
> >
> > Thanks!
> >
> >
>
>
> --
> Chris A. Gueymard, PhD
> Solar Consulting Services
> P.O. Box 392
> Colebrook, NH 03576, USA
> Tel. (603) 237-8550
> Fax (603) 237-5314
>
http://www.SolarCon sultingServices. com
>