mom wants solar on her class C.... i need to do this cheap.

rtate wrote:

Would that mean that theoretically these panels would be capable of putting 23.3 amp hours into my batteries? 2×140 watts÷12 volts =23.3 amps.

As a practical matter how many amp hours could you expect to add to your battery bank on an average day?

Divide by 14.0-14.8V where the battery will be charging.

Assuming the panels are flat mounted and depending upon what month of the year and latitude expect 10-15A. On 12/26/14 in Oceanside, CA on a cloud less day I logged 173AH with 750W so you would get about 60AH.