In 2023, power grids with c20-30% solar variation tend to have intra-day spreads of 9c/kWh, between peak wholesale electricity prices at 8pm and trough prices at 10am. Unusually, night-time electricity prices are 40% higher than day-time prices. This data-file quantifies California electricity prices, on a wholesale basis, at a sample of grid nodes, looking hour by hour in August-2023.