Techno- poetry of the highest quality. Love it.
For a brighter energy future, Geoff Greenfield President Third Sun Solar & Wind Power Ltd. 340 West State Street, Unit 25 Athens, OH 45701 740.597.3111 Fax 740.597.1548 www.Third-Sun.com Clean Energy - Expertly Installed ----- William Korthof <wkort...@eesolar.com> wrote: > Why bother with the DC converters if you only have 2 strings? > > Get a wide-range, dual-channel inverter (Power One 5000) and plug in > the modules > however you like. The bypass diodes in the modules will bypass the > shaded module > sections as appropriate for the conditions, and rest of the modules > (not shaded) will > contribute power used by the wide-input MPPT at the optimal string > voltage. > The input channels are separately controlled, so they both operate at > their optimal > MPPT voltage at all times. > > The input voltage range is extremely wide, 90 to 550 Vdc (Mppt), with > a startup > voltage of 200 Vdc and a maximum Voc of 600 Vdc. That's extremely > flexible gets > you very close to harvesting 100% of the available module output. > > Cost, performance, and reliability seem far better with a PV/inverter > combination > than what you get if you add DC converters to each module. > > /wk > > > > > > Date: Wed, 28 Oct 2009 16:29:56 -0700 > > From: Matt Lafferty <gilliga...@gmail.com> > > To: "RE Wrenches" <re-wrenches@lists.re-wrenches.org> > > Subject: [RE-wrenches] Shade Mitigating DC Device Application > > Message-ID: <f3827d62f9fa4f1e983c525a44f44...@gilligone> > > Content-Type: text/plain; charset="us-ascii" > > > > Esteemed Wrenches, > > > > Your collective wisdom & conjecture is sought in resolving the > > following > > riddle: > > > > There once was a home in the hills. > > With morning sun the roof is filled. > > Blasted mountain rising in the west, > > Makes a shady mess at very best. > > > > "Onward! Fear not!", sayeth the man. > > "Twenty-four modules. Not one less!" > > "Black box of magic for every one." > > "And string inverter plus Island of Sun!" > > > > With fifty-one hundred watts of DC. > > Two series strings of four times three. > > Black boxes of magic, but not by that name. > > At quarter the price are they really the same? > > 'Tis not the matter, least not today. > > To you the group... What do you say? > > > > For greatest performance over time to yield... > > 2 balanced strings of shade and of sun, > > Or put worst shade all onto one? > > Snake-oil merchants say not to worry. > > Magical boxes change dark to light in a hurry. > > What say ye, from out in the field? > > Balance the strings, or not? > > <End> > > > > Some factors to consider.... The site is shade-challenged, primarily > > in the > > afternoon. There will be two strings of 12 modules each feeding a > > single > > inverter. Enphase is off the table for now. Homeowner specifically > > wants to > > do back-of-module DC shade mitigation. The array layout is such that > > configuring the strings so there is a dominant sunny one and > > dominant shady > > one is possible. It is also possible and almost as easy to configure > > the > > strings so they are more balanced with each other. Assuming that > > each module > > is equipped with a black box, will it make any difference which > > configuration gets used? > > > > I have my theory on the subject and am interested in yours. Thanks in > > advance for any and all feedback. > > > > Pray for Sun! > > -------------- next part -------------- > > An HTML attachment was scrubbed... > > URL: > > <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20091028/7546620a/attachment-0001.htm > > > > > > > > > ------------------------------ > > > > Message: 3 > > Date: Wed, 28 Oct 2009 18:21:14 -0600 > > From: Mick Abraham <m...@abrahamsolar.com> > > To: gilliga...@gmail.com, RE-wrenches > > <re-wrenches@lists.re-wrenches.org> > > Subject: Re: [RE-wrenches] Shade Mitigating DC Device Application > > Message-ID: > > <3dff9f8c0910281721r3a729f1er48806fe6aa5a1...@mail.gmail.com> > > Content-Type: text/plain; charset="iso-8859-1" > > > > This jester must ask, with a hint of glee... > > is this off the grid, or is there u-til-i-tee? > > > > Mick Abraham, Proprietor > > www.abrahamsolar.com > > > > Voice: 970-731-4675 > > > > > > On Wed, Oct 28, 2009 at 5:29 PM, Matt Lafferty > > <gilliga...@gmail.com> wrote: > > > >> Esteemed Wrenches, > >> > >> Your collective wisdom & conjecture is sought in resolving the > >> following > >> riddle: > >> > >> There once was a home in the hills. > >> With morning sun the roof is filled. > >> Blasted mountain rising in the west, > >> Makes a shady mess at very best. > >> ** > >> *"Onward! Fear not!*",* *sayeth the man. > >> *"Twenty-four modules. Not one less!"* > >> *"Black box of magic for every one."* > >> *"And string inverter plus Island of Sun!"* > >> > >> With fifty-one hundred watts of DC. > >> Two series strings of four times three. > >> Black boxes of magic, but not by that name. > >> At quarter the price are they really the same? > >> 'Tis not the matter, least not today. > >> To you the group... What do you say? > >> > >> For greatest performance over time to yield... > >> 2 balanced strings of shade and of sun, > >> Or put worst shade all onto one? > >> Snake-oil merchants say not to worry. > >> Magical boxes change dark to light in a hurry. > >> What say ye, from out in the field? > >> Balance the strings, or not? > >> <End> > >> > >> Some factors to consider.... The site is shade-challenged, > >> primarily in the > >> afternoon. There will be two strings of 12 modules each feeding a > >> single > >> inverter. Enphase is off the table for now. Homeowner specifically > >> wants > >> to do back-of-module DC shade mitigation. The array layout is such > >> that > >> configuring the strings so there is a dominant sunny one and > >> dominant shady > >> one is possible. It is also possible and almost as easy to > >> configure the > >> strings so they are more balanced with each other. Assuming that > >> each module > >> is equipped with a black box, will it make any difference which > >> configuration gets used? > >> > >> I have my theory on the subject and am interested in yours. Thanks in > >> advance for any and all feedback. > >> > >> Pray for Sun! > >> > >> _______________________________________________ > >> List sponsored by Home Power magazine > >> > >> List Address: RE-wrenches@lists.re-wrenches.org > >> > >> Options & 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 > >> > >> > >> > > -------------- next part -------------- > > An HTML attachment was scrubbed... > > URL: > > <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20091028/561affab/attachment.htm > > > > > > > > > ------------------------------ > > > > _______________________________________________ > > List sponsored by Home Power magazine > > > > List Address: RE-wrenches@lists.re-wrenches.org > > > > Options & 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 > > > > > > > > End of RE-wrenches Digest, Vol 2, Issue 1107 > > ******************************************** > > Bring back the EV1 electric car! > > _______________________________________________ > List sponsored by Home Power magazine > > List Address: RE-wrenches@lists.re-wrenches.org > > Options & 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: RE-wrenches@lists.re-wrenches.org Options & 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
