How does one implement a price curve? By supply & demand, it is just the result of energy production + energy usage. Are you saying that California has somehow made energy scarce during the day or are you talking about price manipulation?
Exe here is San Diego's pricing from the perspective of consumption only: https://www.sdge.com/residential/pricing-plans/about-our-pri...
Electricity price on the market changes every hour depending on production and consumption. You can trade on it like on any futures market, or as an active participant if you had a large battery or transmission cables. Local utilities here offer "market price + 5% margin" plans to home consumers if you want to take advantage of the lows to adjust your usage.