Equations to answer this question are still being researched but general rule of thumb a system should operate within a 2 % efficiency drop when converting from DC to AC, but as the scale increases more factors are involved as location, sun hours, wire size, trackers, storage, equipment, distances, and loads involved. Found a few web sites that goes into this research more listed here as this group are working with equipment within that scale of range. " Industry Standard " is a variable that will fluctuate over time as solar technologies evolve.
A 40kW Solar Kit can require over 2,300 square feet of space. This 40kW system provides 40,000 watts of DC direct current power. This could produce an estimated 3,200 to 5,600 kilowatt hours (kWh) of alternating current (AC) power per month, assuming at least 5 sun hours per day with the solar array facing South.
https://enphase.com/installers/microinverters
Micro inverters also have 95% maximum efficiency like central inverters even though they are a newer technology. Another factor weighing in favor of the micro inverter market is that micro inverters are much safer than central inverters, since micro inverters convert the electricity to AC at the panel level.
Choosing Between a Central Inverter and a Micro Inverter
The efficiency of an inverter refers to the amount of AC output power it provides for a given DC input. This normally falls between 85 and 95 percent, with 90 percent being the average.
Efficiency of Inverter: Calculation & Equation Guide
- 40kw DC to 28kw AC around 70 % seems to be to low an efficiency rating but of course the other related factors are not mentioned but in a perfect scenario with a full Sun Hour day the AC side should be much higher like 35 kw plus. I would suggest certainly not a standard of efficiency potentials.
Quote from Sophy Cui of Tanfon Solar when asked this same question.
" In fact, we calculate the electricity generated by the solar panels with the sunshine times 3.5hours-6hours, different country, different season, the sunshine times are different, if we calcualte with 6hours best sunshin, then 40KW solar panel can generate 40kw*6hours*80%=192kwh electricity power. if we calcualte with 3.5hours best sunshine, then 40KW solar panel can generate 40kw*3.5hours*80%=112kwh electricity power. 80% is the factor that we consider not all solar panels face totally to the best sunshine, some solar panels might be shaded sometimes."
TANFON Solar
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Timothy Mcbride
CEO/Owner
Sol-Era R & D
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Original Message:
Sent: 07-24-2023 09:27 PM
From: Ella Nielsen
Subject: Question about the Efficiency of Solar Panels
Hi all,
Someone just reached out to me and asked the following question below. Any insight on this would be greatly appreciated it so I can let them know!
"If I have 100 x 400watt solar panels(40kw), is max 28kw AC power coming out of micro inverters at peak sun time consider an acceptable industry standard, or is this too low of efficiency."
Thanks so much,
Ella
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Ella Nielsen
Membership & Engagement Director
American Solar Energy Society
Boulder CO
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