It is possible to dump AC electricity from your inverter although there are a few rules. First the dump load must be smaller in wattage than your inverter. Second…you must use an on/off relay (SSR or standard) that is turned on and off slowly instead of a solid state relay that is controlled by pulse width modulation (PWM). You cannot use PWM with the inverter’s AC as it is very hard on the inverter to make electricity that is turned on and off many times per second. You would need the on voltage to be a volt or two from the off voltage so it doesn’t cycle too fast. Another consideration is that if the inverter were to fail your batteries could be severely overcharged. For those three reasons most folks decide to setup a DC diversion load setup.
With all this in place there was only one thing left to do. Going live with the findings so that the sector may learn from it. Other ethical hackers will hopefully pick up this story and test their own inverters, responsibly disclosing many more vulnerabilities and making the world a little bit safer. Hence, a local newspaper was contacted ( de Volkskrant ) and plans were made to present the findings at SHA2017. In the end, it was decided to leave exact technical details and reproduction steps out of the publication for the time being as no one wants to give black hats an exact step by step guide on how to execute the Horus scenario. Perhaps, full disclosure will happen in time, but not right now.