<div dir="auto">That's a tough call without monitoring, and the difference will be huge depending on SEER rating, insulation, usage habits, and location. You really have to consider worst case, not averages. <div dir="auto"><br></div><div dir="auto">For example, at home I have an older 5-ton, 13 SEER in SW Florida, one of the most challenging areas in the country (high humidity and heat). My annual average is 22kWh per day. We keep the air on 75F generally. However, my average is 40kWh per day in August!</div><div dir="auto"><br></div><div dir="auto">When running it draws just under 3kW.</div><div dir="auto"><br></div><div dir="auto">A new multi speed scroll compressor unit with high SEER would probably cut my usage by 40% based on anecdotal information I've gathered over the years. It would also drastically reduce startup surge. My home is also older with poor windows and doors, so a newer home would have much different performance. </div><div dir="auto"><br></div><div dir="auto">I have a client with a similarly sized house to mine that was built with efficiency in mind and they consume about half of my electricity consumption. </div><div dir="auto"><br></div><div dir="auto">It's a tough design question for sure without data. I don't like these situations. In my opinion you really need to overshoot, especially on the battery capacity if it will be hard to add later. Obviously that gets expensive. </div><div dir="auto"><br></div><div dir="auto">Jason Szumlanski</div><div dir="auto">Florida Solar Design Group</div><div dir="auto"><br></div><div dir="auto"><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Jun 23, 2021, 2:16 PM William Miller <<a href="mailto:william@millersolar.com">william@millersolar.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div lang="EN-US" link="blue" vlink="purple"><div class="m_6678575477293251945WordSection1"><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">Friends:</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">In the old days when a client suggested they might want to run air conditioning equipment on an off-grid system we would just laugh. Now I find I get that request more frequently and clients are willing to pay to acquire enough system capacity to run AC equipment.</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">This means I need to size off-grid installations appropriately for the loads. I have a job pending with a 5 ton AC unit. I cannot find real-life energy specs.</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">I do have a new, fairly efficient 3 ton unit at my grid-connected home and I do have energy monitoring. On a real hot day recently we used a little less than 11kWh in this unit. The max power draw was about 2.5 kW.</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">Here are my questions: </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="m_6678575477293251945MsoListParagraph"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""><span>1.<span style="font:7.0pt "Times New Roman""> </span></span></span><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">Can I linearly extrapolate my usage to a 5 ton unit?</span></p><p class="m_6678575477293251945MsoListParagraph"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""><span>2.<span style="font:7.0pt "Times New Roman""> </span></span></span><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">Do any of you have real-life, measured energy data on modern AC condenser units that you would be willing to share?</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif"">Thanks in advance!</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Verdana","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">William Miller</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif""> </span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">Miller Solar</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">17395 Oak Road, Atascadero, CA 93422</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">805-438-5600</span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif""><a href="http://www.millersolar.com/" target="_blank" rel="noreferrer">www.millersolar.com</a></span></p><p class="MsoNormal"><span style="font-size:12.0pt;font-family:"Arial","sans-serif"">CA Lic. 773985</span></p><p class="MsoNormal"> </p><p class="MsoNormal"> </p></div></div>
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