Carl, I have explored this a bit and William is right. It's complicated! I have used the System advisor model (SAM) to do a cost benefit on this. SAM is a free power system modeling program from NREL that is very extensive and complicated. Here is the download link.
https://sam.nrel.gov/content/downloads There a couple of tutorials to help you get started. Good luck! On Mon, Apr 16, 2012 at 1:32 PM, William Miller <will...@millersolar.com>wrote: > Carl: > > The "sweet spot" is something you have to figure out for yourself. You > need to balance job-specific values against one another. Consider factors > such as: how much you pay for power, how valuable morning and afternoon > production is, the cost of additional PV, the balance between lower tilt > angle production versus more PV that could fit and what weather patterns > are that influence the value of insolation at a given hour or season. > > Maybe you can minimize tilt angle and purchase more PV... Or you can > purchase more land and install more PV... Or build a bigger structure to > add more PV... Consider the price of conservation against the price of > more PV... > > Build some spreadsheets to explore these trade-offs. I can' do this for > you. > > Good luck... > > William Miller > > > > At 04:44 PM 4/15/2012, you wrote: > > Carl is having sending issues, so I am posting this on his behalf. He will > be able to receive your responses on the list, though. > > *From:* Carl Emerson <c...@solarking.net.nz> > *Sent:* 15 April 2012 10:16 p.m. > *Subject:* Array Spacing for optimum performance. > > Hi there, > > Can I raise a design issue with large grid-tied arrays. > > Using William’s spreadsheet for array spacing leaves me with several > questions unanswered. > > Assuming the array is inclined for max year round performance, one could > then space the array for no shading for a certain sun Elevation and Azimuth. > > The question I have is what is the sweet spot when compromising shading > for array spacing in large arrays. > > Narrower spacing means more panels in the array and better output in > summer. > > Wider spacing means better winter performance with less panels and less > annual power production. > > Is there a guideline available to optimise these factors… > > Thanks for your help. > > Carl Emerson > Freepower Co. > Auckland N.Z. > _______________________________________________ > 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 > > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 8.5.455 / Virus Database: 271.1.1/4337 - Release Date: 04/14/12 > 18:34:00 > > ** > > ** Miller Solar > Voice :805-438-5600 > email: will...@millersolar.com > http://millersolar.com > License No. C-10-773985 > > _______________________________________________ > 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 > > > -- Mac Lewis * "Yo solo sé que no sé nada." -Sócrates *
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