Peak efficiency

Peak efficiency is a single percentage on an inverter datasheet. Some datasheets call it maximum efficiency and use the symbol ηmax. Datasheets usually list it next to a weighted figure, such as CEC weighted efficiency or European weighted efficiency. The weighted figure is the same or lower for the same model. For example, the SHP 150-US-20 lists a maximum efficiency of 99.1 % and a CEC weighted efficiency of 99.0 %. The Fronius Symo lists 97.30 % maximum and 96.50 % CEC. Battery inverters and microinverters also carry the figure. The Sunny Island models list 95.3 % to 95.8 % maximum efficiency. The Enphase M250 lists a typical peak of 96.5 at 208 VAC three phase. SMA names EN 50530 as the standard behind the peak efficiency of the SHP 75-10 and STP 60-10. These sources give only the rated values, not how the figure is calculated.

<!-- review notes

• sentence 3: support check: partial - SHP 150 values (99.1/99.0) are shown, and the 97.30/96.50 figures appear, but the passages never name the product as Fronius Symo.
• sentence 4: support check: partial - Sunny Island 95.3–95.8% and M250 typical peak 96.5 at 208 VAC three phase are stated, but the passages don't say Sunny Island is a battery inverter or M250 a microinverter beyond its title (microinverter is in the title); the battery inverter point is not stated.
• sentence 5: support check: partial - EN 50530 for peak efficiency of SHP 75-10 and STP 60-10 is stated, but the passages don't say SMA names it or explicitly say they give only rated values and not the calculation.
• sentence 4: review: partial - The SI maximum efficiencies (95.3-95.8%) and the M250 typical peak of 96.5 at 208 VAC three phase are stated, but the passages never say the SI (Sunny Island) units are battery inverters, or even use the name Sunny Island. -->