PV Gap

Mario Said:

is 2Kilowatts = to 48Kilowatt hours?

We Answered:

The theoretical output of the 2kW array is in fact 48kWh per day, so technically speaking you're right.

But in reality, a 2kW system really can only support about 16kWh/day, and that's stretching it. It doesn't work the way you think it does simply because the sun doesn't shine 24 hours a day. The PV array needs to be oversized to compensate for:

* sunlight hours for the given latitiude
* sunlight intensity (angle and weather)
* storage inefficiency

As a rule of thumb, you need about 3-4x the collector capacity vs. the daily Wh use. So your proposed application is probably in the 6-8kW range for panels. That's about 12-16 panels and some major expense.

That said, 42kWh a day is a lot of juice: a house with an A/C unit might use this much. To make off-grid solar work, some heavy electric users have to go: electric water heat, dryer should be converted to gas. And forget about using the A/C, consider ceiling fans or passive cooling instead.

Even then, consider a backup generator for those intermittent heavy loads and/or cloudy days. Every off-grid house I've seen has one (and I've seen quite a few.)

Readin' room below...