RV, off-grid and 12V systems

Does an Inverter on a 12V Solar Kit Drain the Battery Even With Nothing Plugged In?

Published September 23, 2026 · By the SolarPanelX editors · Prices and specs as of that date, from the pages under Sources

Summary

Yes. Victron's Phoenix Inverter 12/375 draws 5.6 W at zero load, about 134 Wh over 24 hours. Renogy's 2,000 W inverter lists a no-load current under 2.0 A, which works out to as much as about 576 Wh a day at 12 V, close to what a 200 W panel averages per day in Seattle.

Idle draw, five inverters

An inverter's job is converting DC from panels or batteries into the AC that household appliances use. A system that only runs 12 V gear never needs that conversion. Once an inverter is added and switched on, it keeps drawing power with nothing connected.

Model	Continuous output at 25°C	Zero-load draw	Over 24 hours	In ECO mode
Victron 12/250	200 W	4.2 W	about 101 Wh	0.8 W
Victron 12/375	300 W	5.6 W	about 134 Wh	0.9 W
Victron 12/800	650 W	6.5 W	156 Wh	1 W
Victron 12/1200	1,000 W	10 W	240 Wh	1 W
Renogy 2000W 12V	2,000 W	under 2.0 A (under 24 W at 12 V)	under 576 Wh	not listed

In Victron's ECO mode the inverter drops to standby when the load falls below a preset value. The minimum setting is 15 W, and by default it checks again every 2.5 seconds. Renogy's datasheet gives the no-load figure as a current; the conversion to watts is ours.

Against a day of 200 W panel output

Taking NLR PVWatts per-kilowatt annual estimates for a south-facing array at a 20-degree tilt, scaling to 200 W and dividing by 365 gives a daily average of about 596 Wh in Seattle, 707 Wh in New York, and 962 Wh in Phoenix. Left on around the clock, the 2,000 W unit would use up nearly all of Seattle's average day at idle. The 12/375's 134 Wh is a little over a fifth of it.

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Sources

We have not tested these products. Specs, prices, stock and terms are as published on these pages on the date above and can change; check the manufacturer or retailer before you buy.

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