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HOLD60
60.00 Hz stable
You run a power grid for one day. Demand never stops moving and your power plants are slow. Fall below 59.3 Hz and neighborhoods go dark.
Today's grid Daily #1One grid per day, the same for everyone
30-second tutorial All five scenarios Write a dispatch policy in JS
Five hand-built days: spring, heatwave, winter storm, windless, AI boom. No sign-up, no tracking, keeps running offline once loaded.
Each day is seeded. Everyone gets the same weather, so grades are comparable.
Called once per simulated minute (1,440 times). Return setpoints in MW. Anything you leave out keeps its last value. Your score is societal cost: fuel + start-ups + $10,000 per MWh of blackout + $100 per tonne of CO₂ (lower is better). Unknown keys and non-numbers are ignored, with a warning in the console below naming the key.
return {
coal: 1200, gas: 900, peaker: 0, // thermal targets (units start/stop automatically)
commit: { gas: 4 }, // optional: keep at least N units online
wind: 3000, solar: 3500, // curtailment caps
battery: -300, // + discharge, - charge (auto frequency response adds on top)
dr: true // call demand response (limited calls)
}
state: t (minute 0..1439), frequency, deviation, demand, generation, imbalance, fleets.{nuclear,coal,gas,peaker} (output, online, starting, capacity, onlineMW, unitMW, rampPerMin, startMin, minFrac, cost, co2), fleets.{wind,solar} (available, output, capacity), fleets.battery (soc, socFrac, mwh, mw), dr (callsLeft, active, pending), forecast.{demand,wind,solar}[minute].
memory is yours to keep anything between calls. console.log works. Each call gets 250 ms; loop forever and the run stops, not the page.