If all goes as scheduled, by the end of this month, my home will have enough solar capacity on it to offset just over 100% of the house’s current electricity usage plus typical local travel for two plug-in hybrids.
My best estimate is that, including the 30% federal subsidy, the system will be cash flow break even after 14 years and have a roughly 6% ROI over the 30-year warrantied life of the panels. That estimate assumes electric rates will increase by roughly 3% annually. I guess if rates go up faster, the break even will be sooner and the ROI better…
Note that my house has lots of natural gas appliances (furnace, stove, water heater, clothes dryer, outdoor grill), so it won’t be fully energy independent. That said, as appliances age out, it may make sense to consider converting, particularly if we find ourselves consistently generating more electricity than we use.
For instance, the air conditioner is a 13-SEER model that’s roughly 20 years old and on a previous generation of coolant. When that gives up the ghost, it may make sense to install a high efficiency heat pump system that uses less electricity when cooling while also acting in lieu of the furnace to heat the house in the winter.
Regards,
-Chuck