I need to power a mains unit that takes a maximum of 25w.
The question is, if I buy a 150w inverter, does it take much less power than a 300w inverter. A 300w inverter would probably be more useful down the line, but less power consumption is also important. I would like to use the appliance that takes 25w a reasonable amount, so if a 150w inverter is going to use substantially less power than a 300w inverter on a 25w load, I would prefer to buy the 150w inverter.

What would be the difference on 12vDC current wise from a 150w to 300w inverter with a 25w mains load?

Hi Dasher,

It really depends on the inverter design. I remember a 700 watt inverter (Power Star, I think) that drew less power with a 25 watt load than most 150 watt inverters.