<div dir="ltr"><div dir="ltr"><div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">Enphase IQ8 microinverters will absolutely leak some power back to the grid when set to a no-export grid profile. How much, and if that is detrimental to the generator is another question. I suspect if the generator is large enough relative to the PV array, the impact will be nil, but I would not take the risk. </div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif"><br></div><div class="gmail_default" style="font-family:arial,helvetica,sans-serif">I don't think the fast switching really does the trick in terms of not exporting. That function relies on the consumption CTs connected to the Gateway, which in turn communicates with the microinverters. Aside from the CTs not being totally accurate, I don't see how that communication loop could be fast enough.</div><br clear="all"></div><div><div dir="ltr" class="gmail_signature"><div dir="ltr"><br>Jason Szumlanski<div><span style="color:rgb(51,51,51);font-family:Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:13px">Principal Solar Designer | Florida Solar Design Group</span><br style="color:rgb(51,51,51);font-family:Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:13px"><span style="color:rgb(51,51,51);font-family:Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:13px">NABCEP Certified Solar Professional (PVIP)</span><br style="color:rgb(51,51,51);font-family:Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:13px"><span style="color:rgb(51,51,51);font-family:Roboto,RobotoDraft,Helvetica,Arial,sans-serif;font-size:13px">Florida State Certified Solar Contractor CVC56956</span></div><div><font color="#333333" face="Roboto, RobotoDraft, Helvetica, Arial, sans-serif">Florida Certified Electrical Contractor EC13013208</font></div></div></div></div><br></div><br><div class="gmail_quote gmail_quote_container"><div dir="ltr" class="gmail_attr">On Wed, Jan 21, 2026 at 12:09 PM scot.arey--- via RE-wrenches <<a href="mailto:re-wrenches@lists.re-wrenches.org">re-wrenches@lists.re-wrenches.org</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"><div class="msg-242233186207474644">
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Good day,</div>
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I many years ago watched the fast-switching capabilities of the IQ-8 microinverters to produce only what demanded of the MI, and wondered if it might have application in a grid-tied system that is served by a whole-house generator.</div>
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We have the opportunity to install grid-tied-only array of 24 IQ8 but all the MIs will be on the customer side of an auto-transfer switch and generator. We want to leverage using existing building wiring to carry the solar and all solar sizing meets the 120%
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But I know that grid-tied solar on the customer load-side of the transfer switch means no place for full solar power production to flow to when the grid is not available...but then I thought back to that fast switching capability: is there a way to ensure
the IQ8 don't backfeed a generator when it is operating for a grid anomaly?<br>
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I suspect the answer is "are you nuts???" but that video of capability got me thinking, "why not?" and if not, how is it - what tells the MI to cease production? - when it is within a full and proper ISC/ESS system design?<br>
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<b>Howard "Scot" Arey</b></div>
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NABCEP PV Installation Professional</div>
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