No way California retail energy price is $0.138/kWh. For example:
PG&E E-1 Residential rate: $0.19979/kWh Baseline, $0.27612/kWh 101%-400% Baseline, $0.40139/kWh 401%+ Baseline
Baseline varies by region. Most coastal areas are about 10kWh/day.
E-1 is the most common residential rate plan. The EV rate is $0.12502/kWh to $0.45389/kWh depending on season and TOU period. So, charging your car overnight is cheap, less than $0.13/kWh all year round, but your A/C and Plasma TV is very costly if you use it in the afternoon and evening.