<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Geoff,<div><br></div><div>When you mentioned "plenty of partial shading", that settled the issue for me. Every cell in Uni-Solar modules have a bypass diode allowing them to handle shading better than any other module I know of. For potentially shaded areas or high ambient temperatures, it is our module of choice. After 6 years of selling and installing Uni-Solar, we have only had one failure. Their performance here in our very hot climate is outstanding.<div><br></div><div>As for the mismatching module sizes, the 68 is half the voltage of the 136 but the same current. They both use the same cells. If you are only using a single string the MPPT controller will simple adjust for the Vmp of that circuit. However, as with any array, if you have multiple strings with mismatched string voltages, the controller will "see" a lower average and you will, at the least, be wasting power. The bypass diodes have nothing to do with mismatched strings.</div><div><br></div><div>If you are comparing arrays with different angle of incidence and without shading, the one most perpendicular to the sun will perform the best.<br><div><br><div apple-content-edited="true"> <span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; "><div><div>Kindest Regards,</div><div><br></div><div>Larry Crutcher</div><div>Starlight Solar</div><div>11279 S. Glenwood Ave #11114</div><div>Yuma, AZ 85367</div><div>(928) 941-1660</div><div><br></div><div><a href="mailto:larry@starlightsolar.com">larry@starlightsolar.com</a></div><div><a href="http://www.starlightsolar.com">www.starlightsolar.com </a></div></div></span></span></span></span><br class="Apple-interchange-newline"></div></span> </div><br><div><div>On Oct 31, 2008, at 8:08 AM, Geoff Greenfield wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div style="font-family: 'Times New Roman'; font-size: 12pt; color: rgb(0, 0, 0); "><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">As a follow up to my uni-solar post (and thanks to all who provided feedback), I have a second request:</div><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "> </p><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Any references to recent side-by side "shoot-outs" between Unisolar and conventional crystaline PV? Scientific studies? Your own wrench thoughts?</div><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "> </p><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I am more and more often encountering confused customers that are considering unisolar systems at zero-tilt (we are at 40 degrees N), with plenty of partial shading, after getting a pitch about all sorts of advantages of Uni-Solar. I think that this product has it's role and I occasionally sell it... But I am frustrated when I truly believe I can deliver a better net energy production with a tilted crystalline solution (avoiding the shaded areas). <span class="Apple-converted-space"> </span><br></div><div>For a brighter energy future,<br><br>Geoff Greenfield<br></div></div></span></blockquote></div></div></div></div></body></html>