PV Watts does not consider snow. So, if you are in an area that snow coverage is an issue then you have become the decider based on what your best instincts and your experience tell you. I've got some second story (not workable for a roof rake unfortunately) low sloped roofs for clients that can stay snow covered for weeks at a time. But I know that going in and I take PV watts and de-rate the 5 months that we get significant snow here in northern Vermont and no one is surprised and disappointed with the poor winter production.
Dave Palumbo -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Benn At DayStarSolar Sent: Tuesday, May 14, 2013 7:10 PM To: RE-wrenches Subject: Re: [RE-wrenches] SE or SW Jesse, A good decision can be based on, among other site/load specific details, the site's "micro-climate". Do they tend to have clear mornings and cloudier afternoons/evenings? ...or cloudy/foggy mornings and clearer afternoons/evenings? Maybe throw the different directions into PVWatts and see what it says, since it is based on weather history (isn't it?) Good luck. benn Sent from a 'smart' phone, with touch screen keys. Please excuse shortcuts and typos. On 2013-05-14, at 4:34 PM, Jesse Dahl <[email protected]> wrote: > Hello, > > I was asked to look at a site today for a homeowner looking for a grid-tie with battery-back up. They are Doomsday Preppers for lack of a better term and want certain loads if and when the grid goes down for good. Aside from parts selection, they have two roof lines, one facing SE one facing SW. the SW is very low slope and is only accessible with a ladder and climbing on the roof, the other is SE, much steeper slope and accessible from the ground or deck. I mention the access because of snow removal. We had lots of snow last year and I spent lots of time on my roof removing 8" snow falls. Both have good solar access. > > I'm inclined to chose the SE roof line, but I am interested in arguments for the SW. > > Thanks! > > Jesse > > Sent from my iPhone > _______________________________________________ > List sponsored by Home Power magazine > > List Address: [email protected] > > Change email address & settings: > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org > > List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org > > List rules & etiquette: > www.re-wrenches.org/etiquette.htm > > Check out participant bios: > www.members.re-wrenches.org > _______________________________________________ List sponsored by Home Power magazine List Address: [email protected] Change email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org _______________________________________________ List sponsored by Home Power magazine List Address: [email protected] Change email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules & etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
