Dana, I have never compared these two side-by-side, but I do know from experience that it is critical to use the proper cropping margins when transferring images in to the Pathfinder Assistant Software. Slight changes in the margins of the field photographs of the Pathfinder tool can have a significant impact on the available access numbers. If you have never tried it, play around with different margins using the same photo and you'll see what I mean. Refer to the manual for the proper location of the crop (from p. 30 of Version 5, 2011): "There are four crop handles (left, top, right, bottom). These handles should be dragged so that the translucent box frames the outside of the plastic Pathfinder housing." Mark
[USLE Email Signature (240x42)] Mark Richardson Production Manager CELL: 518-965-4148 From: RE-wrenches [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Allan Sindelar Sent: Tuesday, October 28, 2014 6:38 PM To: RE-wrenches Subject: Re: [RE-wrenches] Pathfinder vs. Suneye Dana, I'm not going to answer your question directly, but rather I'd like to add to Ray's comments. In short. use the SunEye for grid tie work; use the Pathfinder for off grid. If you don't do off grid (most installers don't any more, if they ever did) don't bother with the Pathfinder. Off grid seldom if ever deals with multiple roof angles, as modules aren't typically mounted on roofs. Details: 1. Grid tie is competitive, so you want the most accurate estimate of production. I believe the SunEye is more accurate, or at least more "liberal" in its output. 2. Your competitors will most likely use the SunEye, so you'll need to offer its level of apparent professionalism, as well as match their output projections. 3. For off grid, I want the inherent conservatism of the Pathfinder; for grid-tie, not so much. I have almost zero history of customers' off grid systems being undersized, in large part because of the inherent conservatism of the Pathfinder, combined with our 37º latitude, as Ray mentioned (meaning we're at the outer edge of the 6º latitude template spread), and also combined with our high-elevation, dry-air insolation often exceeding the standard 1,000 w/m2. Together this meant that my systems typically and routinely exceeded their projected output. Nobody has ever complained about that. 4. Grid tie customers never go on the roof with the designer/salesperson to look at a sunpath chart. They just want the results - a PV system that looks good and saves them money. Off gridders are usually way more involved in the design and customer education process. The Pathfinder sunpath chart is so simple to read that doing charts while picking an array site is a shared part of the educational part of the design/sales process. So it leads to the treasured "ah-hah!" moment when the client really gets what's going on, and gets fully engaged in the design of "their" system in the process. They're two different tools serving completely different purposes. I prefer the analog nature of the Pathfinder, but not for the usual and predictable reasons. Allan Sindelar www.sindelarsolar.com<http://www.sindelarsolar.com> Allan Sindelar al...@sindelarsolar.com<mailto:al...@sindelarsolar.com> NABCEP Certified PV Installation Professional NABCEP Certified Technical Sales Professional New Mexico EE98J Journeyman Electrician Founder (Retired), Positive Energy, Inc. 505 780-2738 cell On 10/28/2014 3:32 PM, Ray Walters wrote: I've not done a side by side comparison, but the Pathfinder seems to be slightly conservative, especially depending on which latitude sheet you are using. I sometimes switch sheets and try both, when the latitude is close to falling between (ie 37 deg, and there is 37 to 43 sheet or a 31 to 37 sheet) Checking against actual sun locations at the solstices, it seems to be close, but I think they would rather err on the side of caution. I've used the Path finders for decades, and find them ideal for discussing shading issues on site with the customer, as every one can look at it at the same time. For more complicated shading analysis, I can see the Suneye being more useful. Depending on the situation, I could see using both, but the Pathfinder is better for off grid, as we don't have accurate insolation values at these remote locations, so detailed analysis has limited value anyway. We're primarily looking at which trees need to be trimmed. R.Ray Walters CTO, Solarray, Inc Nabcep Certified PV Installer, Licensed Master Electrician Solar Design Engineer 303 505-8760 On 10/28/2014 3:19 PM, Dana Brandt wrote: Hi Wrenches, We've been using the Pathfinder along with the Pathfinder Assistant software for several years and mostly like it. My concern with it is there's no way to combine two or three shading images to account for a string of modules spanning those different shading conditions. I've spoken with the Pathfinder folks and they don't seem to understand or acknowledge that limitation. How have you dealt with this? So I bought a Suneye. Their software can apparently calculate string shading including multiple solar access readings. I took both the Pathfinder and the Suneye out on my next site assessment and have run the results of side by side measurements. The Suneye is showing about 10-15% better solar access for each measurement that the Pathfinder Assistant software. I'm concerned to see such different numbers. Has anyone else done a side by side comparison? What have you seen? Thanks, Dana Dana Brandt Ecotech Energy Systems, LLC www.ecotechenergy.com<http://www.ecotechenergy.com> d...@ecotechenergy.com<mailto:d...@ecotechenergy.com> 360.318.7646 _______________________________________________ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org<mailto:RE-wrenches@lists.re-wrenches.org> Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules & etiquette: www.re-wrenches.org/etiquette.htm<http://www.re-wrenches.org/etiquette.htm> Check out or update participant bios: www.members.re-wrenches.org<http://www.members.re-wrenches.org> _______________________________________________ List sponsored by Redwood Alliance List Address: RE-wrenches@lists.re-wrenches.org<mailto:RE-wrenches@lists.re-wrenches.org> Change listserver email address & settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/maillist.html List rules & etiquette: www.re-wrenches.org/etiquette.htm<http://www.re-wrenches.org/etiquette.htm> Check out or update participant bios: www.members.re-wrenches.org<http://www.members.re-wrenches.org>
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