If you look at some solar info domestic hot water takes a lot of energy with electric, though there are efficient designs, but they still take power that might be dumped into the EV or sold to the grid. If you wanna cook using gas, then one or two of these units using sunlight and storing the hydrogen while the sun shines, might make more of an excess than needed for cooking, it works constantly while the sun shines whether you need the hydrogen or not, so after the tank is full it heats the water tank instead of wasted! One or two of these over the kitchen along with PV panels on the roof and a safe cheap sodium battery bank in the basement along with a small hydrogen tank outside could do ya if you live in the right place and circumstances and wanna cook with gas. Cooking and heating domestic hot water are major energy users and will reduce the load on the PV and battery system a lot, so will a heat pump, more energy for the EV plugged in outside.