Read the case study (https://www.opto22.com/support/resources-tools/documents/2137-application-brief-wind-farm-energy-management)
When these California wind turbines were installed (up to 30 years ago), owners could just turn them on and make money. But now it's different. Now returns are based on a minute-by-minute market price for electricity. If turbines are on while the price is high, owners make money. If they're on when the price dips into negative territory, owners LOSE money. And if the regional authority demands all turbines be turned off, owners must comply within 10 minutes or face stiff penalties.