Fortunately Martin has distilled the most relevant parts out and created a spreadsheet that can be downloaded from the Tesla site. There is no simple answer to the question of how much EV charging capacity your house can support. It depends on a multitude of variables such as what appliances and other loads you use and in what combinations as well as the wiring setup of your house. Martin would like readers to download his spreadsheet, fill it out and post the results in the comments of his post. The results will help Tesla determine what kind of charging rate potential customers can support when designing new products. If you have an older house with corresponding wiring, you may well find that you need to upgrade your home wiring before you get an EV.