Because a refrigerator is an almost an essential appliance, along with being one of the most energy consuming, understanding it's demands is essential for offgrid planning. Many who are new to solar underestimate it's needs resulting in dissapointment, to better understand it's demand I recorded the energy in real use to compare it against energy guide figures, which are done in controlled conditions.
The refrigerator used for the logging is a Panasonic nr-bw415 vn, with bottom draw freezer 123 liter (4 cf), ref. 284 liter, (10cf) inverter type, R 600a refrigerant , energy guide 311 Kwh per annum.
The logging was done over a 4 week period, the indoor temperature was between 27 and 36°C, the higher daily consumption figures are in direct correlation to the warmer days. Total for 4 weeks 34 Kwh multiplied by 13 = 442 Kwh per annum. The time of year was neither the hottest nor coolest, so as to obtain an average, no effort to conserve, just regular use.
One thing to remember, for the benifit of the newbies, is the DC-AC inverter has to be on 24/7 and it's needs may be close to or sometimes higher than the appliance itself. This particular unit was tested on a 300W inverter and worked, so having a small DC-AC inverter for night use will help reduce precious battery capacity, though this may not be possible with a regular non inverter compressor.
As a side note, I did a day log on a small Hitachi bar fridge with R 143a refrigerant , it's consumption was similar.
The refrigerator used for the logging is a Panasonic nr-bw415 vn, with bottom draw freezer 123 liter (4 cf), ref. 284 liter, (10cf) inverter type, R 600a refrigerant , energy guide 311 Kwh per annum.
The logging was done over a 4 week period, the indoor temperature was between 27 and 36°C, the higher daily consumption figures are in direct correlation to the warmer days. Total for 4 weeks 34 Kwh multiplied by 13 = 442 Kwh per annum. The time of year was neither the hottest nor coolest, so as to obtain an average, no effort to conserve, just regular use.
One thing to remember, for the benifit of the newbies, is the DC-AC inverter has to be on 24/7 and it's needs may be close to or sometimes higher than the appliance itself. This particular unit was tested on a 300W inverter and worked, so having a small DC-AC inverter for night use will help reduce precious battery capacity, though this may not be possible with a regular non inverter compressor.
As a side note, I did a day log on a small Hitachi bar fridge with R 143a refrigerant , it's consumption was similar.
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