<div dir="ltr">Hi Chris -<div><br></div><div>I'd recommend reading through the PVWatts Calculator and manual: <a href="https://pvwatts.nrel.gov/">https://pvwatts.nrel.gov/</a> </div><div><br></div><div>If you click the help button you'll get to the manual, and you can simulate a sample system by just entering in a zip code. The default settings estimate losses at about 14% prior to the inverter efficiency loss.</div><div><br></div><div><a href="https://pvwatts.nrel.gov/">https://pvwatts.nrel.gov/</a> </div><div><br></div><div><div><img src="cid:ii_jzvbflrz0" alt="image.png" width="562" height="340"><br></div><div><br></div><div>August</div><div>Luminalt</div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Aug 28, 2019 at 6:31 AM Christopher Warfel <<a href="mailto:cwarfel@entech-engineering.com">cwarfel@entech-engineering.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">Hi Dan, Sorry for the confusion.<br>
<br>
Maybe an example would help. Take a 2000 w dc multimode system that is <br>
coupled with a 3600 w ac rated multimode inverter. What percentage of <br>
the dc capacity is inverted into ac capacity. So, roughly 2000 x .9 <br>
(wiring and similar losses from array to battery) x .95 for an assumed <br>
5% usage to charge/float the batteries x .98 for dc to ac inverter <br>
efficiency makes me think that 2000 x .9 x .95 x .98 * (4.5 x 365) <br>
yields = 2,752 kWh annually. The utility is assuming roughly 3600 x .98 <br>
x (4.5 x 365) {if they are assuming anything at all} = 5,368 kWh revenue <br>
lost. The regulatory assumption overestimates the capacity factor by @49%.<br>
<br>
I'll post to the WRENCHES too to help clarify hopefully. Chris<br>
<br>
On 8/28/2019 9:10 AM, Dan Lepinski, P.E. wrote:<br>
> OFF-LINE REPLY<br>
><br>
> Hello Chris,<br>
><br>
> The wording of your question is confusing. You ask about the percentage of DC capacity vs AC power output, then add batteries into the mix.<br>
><br>
> What system topology is the focus of your query?<br>
><br>
> I'll be glad to do what I can to assist. Just need clear direction on the configuration.<br>
><br>
><br>
> Regards,<br>
><br>
><br>
> Dan<br>
><br>
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