Carl,<div><br></div><div>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.</div>
<div><br></div><div><a href="https://sam.nrel.gov/content/downloads">https://sam.nrel.gov/content/downloads</a> </div><div><br></div><div>There a couple of tutorials to help you get started.</div><div><br></div><div>Good luck!<br>
<br><div class="gmail_quote">On Mon, Apr 16, 2012 at 1:32 PM, William Miller <span dir="ltr"><<a href="mailto:william@millersolar.com">william@millersolar.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div>
Carl:<br><br>
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.<br><br>
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...<br><br>
Build some spreadsheets to explore these trade-offs. I can' do this
for you.<br><br>
Good luck...<br><br>
William Miller<div><div class="h5"><br><br>
<br>
At 04:44 PM 4/15/2012, you wrote:<br>
</div></div><blockquote type="cite"><div><div class="h5">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.<br><br>
<font face="Tahoma"><b>From:</b> Carl Emerson
<<a href="mailto:Carl@solarking.net.nz" target="_blank">Carl@solarking.net.nz</a>><br>
<b>Sent:</b> 15 April 2012 10:16 p.m.<br>
<b>Subject:</b> Array Spacing for optimum performance.<br>
</font> <br>
<font color="#0000FF"> Hi there,<br>
<br>
Can I raise a design issue with large grid-tied arrays.<br>
<br>
Using William’s spreadsheet for array spacing leaves me with several
questions unanswered.<br>
<br>
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.<br>
<br>
The question I have is what is the sweet spot when compromising shading
for array spacing in large arrays.<br>
<br>
Narrower spacing means more panels in the array and better output in
summer.<br>
<br>
Wider spacing means better winter performance with less panels and less
annual power production.<br>
<br>
Is there a guideline available to optimise these factors…<br>
<br>
Thanks for your help.<br>
<br>
Carl Emerson<br>
Freepower Co.<br>
Auckland N.Z.<br>
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<br></blockquote></div><br><br clear="all"><div><br></div>-- <br><div><br></div><div><font color="#305A78" face="'times new roman', serif"><br></font></div><div><br></div>Mac Lewis<br><br><span style="font-family:'Times New Roman';font-size:medium;color:rgb(255,153,0)"><b><font face="Arial, Helvetica, sans-serif" size="3"><p align="left">
<font color="#000000" face="Verdana, Arial, Helvetica, sans-serif"><span style="font-size:small"><span style="font-family:arial;font-weight:normal;color:rgb(48,90,120)"><font face="'times new roman', serif">"Yo solo sé que no sé nada." </font><span style="font-weight:700;color:rgb(104,104,104)"><font face="'times new roman', serif">-Sócrates</font></span></span></span></font></p>
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