I know what you mean.....I haven't seen the sun in 4 days here in Orlando. I only want to use the bilge pump when the power goes out and then switch back to the regular pump when the power comes back through a relay. The 12v bilge pump will be controlled by a relay to only come on when the power goes out and will be running off the 12v gel battery which is been trickle charge from the solar panel on a everyday basis. I'm hoping the battery is at full charge when I need it since is only been used for power outages only....