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Run the Grid.

How does a market pick a price?

Part 1

Supply and demand: a boba shop

$8
Part 2

Now electricity: each step is a power plant

7 PM
Price

The bid stack

Supply bidPriceQuantity (GW)
drag ↕
cheapest bids at the bottom
Demand to meet
31.5 GW
Accepted: 0 GW
Part 3

Every 5 minutes, a new price. Add them up: a whole day.

Time
12:00 AM
Demand=Supply
15.5 GW = 15.5 GW
Price
$35
Bid stack, live
BidPriceGW
Demand
cheapest at the bottom
See it live CAISO Today's Outlook → California's real demand curve today, next to the forecast caiso.com/todays-outlook
Part 4

Forecasting: guess tomorrow's demand

Clues→Math→Forecast

1. Clues move together

2a. A straight line: hotter day → more demand

2b. What if everyone gets home at once?

Which math fits better?

Made-up numbers for teaching.