Topic

Is an inverter/charger different than an offgrid inverter?

Or is it just the names- a way of promoting? Does the inverter/charger act like a charge controller?

Comments

Dave,

Back when PV systems were all off-grid, systems were designed "a la carte" and based on the 12VDC PV Module. The designer would match up a charge controller with a battery bank, then add as many PV modules as they could afford to charge the batteries at 12V.

Appliances would then be run at 12VDC or, in some cases, an inverter would be used at a relatively low 80% efficiency to power AC appliances.

Two things happened to change that situation: Inverters became more efficient and they became certified for grid connection under UL's 1741 standards.

The effect of this development was that inverters started approaching 95% efficiency and it became viable to just run one's appliances on AC power by converting DC battery power.

The inverter/charger is a package of inverter and battery charger (charge controller). An off-grid inverter is a DC to AC inverter which may or may not be UL 1741 listed, depending on the make/model.

So now, we have a wide variety of inverters and charge controllers - and combo units to choose from - to satisfy a wide variety of design requirements.