There could be problems with the inverter or wiring that could easily result in metering issues. Also, make sure the higher bill is for the energy (kwh) component of the bill and not for the capacity (KW) component which may in some cases may be ratcheted up for peak useage. Also, if you are some type of “net metering” program you may not be getting credit for energy fed back into the grid.
As to leaks, call a good roofer, not the electrician