Refrigerator Day

PV data plot

This is a high-resolution capture (3 minute sampling interval) of the (now single, 3-panel) PV system running a large, not-particularly-efficient refrigerator for a day. The refrigerator was plugged in in the morning, and unplugged after sunset. Later that night we enjoyed some solar television.

The inverter now consumes 25 W of average power, and the refrigerator takes an average of 55–75 W, depending on ambient temperature. Each 130 W panel, considering day/night, season, geometry of illumination, and inefficiencies, can handle about 20–25 W in San Diego. So one of the three panels takes care of the inverter alone. The two other panels are not sufficient to manage the refrigerator full-time. But I can relieve some of peak demand by running the fridge during the day, as seen here.

We see the fridge cycling on and off all day. Once the red curve is higher than the cyan spikes, the battery is being charged while the fridge is running off of 100% solar! Indeed, the battery is able to reach 100% during the day, lots of time is spent in absorption stage (during which time the current needed to maintain absorption stage steadily declines, as seen by red line when the fridge is off).

Previous Data Set | Next Data Set

Main Page