I am on the process of making assumption how much capacitance/joule/watt is required on average supercapacitor as household' energy storage system. I plan the design for energy hub to be charged by electrical grid on night, and by the sunlight on daylight. I've found that for normal household energy use, the power supplied by meter (9.2 kVA on average) should suffice. In theory, this allows you to simultaneously supply devices with a maximum power of 9.2 kW or 9200 watts. Does it mean that ideal household supercapacitor for renewable energy resource (sunlight) on energy hub is 50% or...? Any help would be appreciated. Thank you.
Here's a quick calculation, using an example 500 F, 16.5 volt supercapacitor (https://www.mouser.com/datasheet/2/257/Maxwell_16VModule_DS_1009363-10-1179674.pdf) Assume your converter electronics can work between 5 and 15 volts with a 90% efficiency. At 5 volts, this capacitor would have energy ( 1/2 * C * V^2) of 12,500 joules. At 15 Volts it would have an energy 112,500 joules. Subtract and you would have 100,000 joules to work with if the capacitor was charged to 15V and discharged to 5V.
Since a joule is a watt-second, you have 100,000 watt-seconds, and at 9200 watts you have a theoretical 10.9 seconds (100,000 / 9200) of capacity in each capacitor of this size. Throw in your 90% efficiency and you are just under 10 seconds of capacity for each 500 F, 16.5 volt capacitor. So calculate the number of seconds you want to run the household, and you will see how many capacitors you need.