We have a grid-tied all electric home plus an MS, and hopefully soon a 3, powered by 11.4 kW of solar PV, and during power failures, a Kohler 18 kW propane generator. In the next few days we be getting a PW2, and likely soon thereafter, a 2nd one. The question is how the PW2 gateway interfaces with the generator. I am familiar with how the Sunny Island works during a power failure to fire up the generator if either the battery bank needs charging or the demand in the house exceeds the battery backup capacity in kWs, as would likely be the case with the PW2s when the cars are charging. I have been assured by my installers that the PW2 gateway will also use the generator in an intelligent way, but have seen no evidence so far that an interface exists. The only thing that is needed for control of the Kohler generator is a contact closure; I currently I have a line running to the house and a switch there so that I can turn the generator off during periods of low usage to save propane. While I am certain Tesla must have considered this need and has designed the gateway appropriately, it would be nice to hear from anyone with direct knowledge of this capability.