Voxel Valley
You are the whole utility · 3D
A block island, dark villages, and no power system at all. Build the dams, nuclear, gas and solar — then the towers and substations to carry it — until every window glows. Every new valley deals a different hand.
- Generate high, step down, deliver low
- Dams need rivers; reactors need cooling water
- Drought years and missing pipelines change the answer
Damkeeper
You are the dam operator · 3D
Three days on shift at one dam. Rain is coming, the lake is rising, and you hold two levers — the turbines and the spillway. Keep the dam safe, the town dry and the fish alive, and turn the rest into electricity.
- The pool rises by inflow − outflow, live
- Make room for a storm before you are sure of it
- Every spilled drop is power thrown away
Boomtown
You are the utility planner · 3D
The town grows 30% a year for six years, and you are its whole utility. Plants take years to build, the sun clocks off at dinner time, and demand compounds like rent. Order early — or watch the windows go dark.
- Capacity is bought years before it is needed
- Firm power vs. weather power
- Blackouts starve the budget that would fix them
River Doctor
You are the aquatic biologist · 3D
Catch ten fish, identify every one from its field marks, release every one — then diagnose the river. Sensitive species only live in clean water, tough ones live anywhere, so the tally sheet is a water test made of fish.
- Bioindicators: the species mix IS the data
- Field ID: ear flaps, whiskers, tails, stripes
- Absence is evidence — the loudest kind
Grid Balance
You are the dispatcher
Electricity cannot be stored in the wires. Whatever the valley uses this second, you must generate this second. Get it wrong and the whole system speeds up or slows down.
- Supply and demand, balanced every instant
- Why 60 Hz is the number that matters
- Cheap and slow vs. fast and expensive
Steam Cycle
You are the plant operator
Coal, gas and nuclear are three different ways to boil water. Downstream of the fire the machinery is nearly identical — and two thirds of the energy goes out of the cooling tower no matter which you pick.
- A reactor is a very fancy kettle
- Where the wasted two thirds actually goes
- Why gas ramps and coal does not
Line Loss
You are the transmission planner
Route power across the valley without losing it on the way. Push it at low voltage and it vanishes into heat; double the voltage and you lose a quarter as much. That is the whole reason those towers are so tall.
- Losses go as the square of current
- What transformers are actually for
- Ohm's law, with consequences
Flood Week
You are the river operator
A storm is coming and the forecast is uncertain. Empty the reservoirs too early and you waste the water. Too late and Riverton floods. You have to decide before you know.
- Storage, flow and travel time
- Acting on an uncertain forecast
- Flood control is why the dams exist
Lockmaster
You are the lock operator
Almost nobody thinks about how a barge gets past a dam. Raise and lower barge tows through the lock, and find out how much steel one chamber of water can lift.
- Buoyancy: why loading changes the draft
- One barge ≈ 60 semi trucks
- Every lock cycle spends water
Power Trader
You run the trading desk
Buy power when it is cheaper than making it yourself; sell when it is dearer. Commit before tomorrow happens. Sometimes the price goes below zero and you are paid to take it.
- Why prices spike — and go negative
- Marginal cost sets the price
- Hedging: cheap insurance, expensive regret
Bobcat Mountain
You are the storage operator
A lake on top of a mountain. Pump water uphill when power is cheap, let it fall when power is dear. About a fifth of the energy vanishes on the round trip — that is the price of storing anything at all.
- Energy vs. power: two different limits
- Round-trip efficiency
- Why grid storage exists
Dam Works
You are the design engineer
Pick a dam for the site you are given, then send a flood at it. Water pushes four times as hard when it gets twice as deep — which is why the answer changes with every valley.
- Force grows with the square of depth
- Factor of safety, and why 1.1 is not enough
- Geology decides the design
Valley 1933
You are the whole authority · capstone
Ninety years in one sitting. Start with an eroded, unelectrified valley and decide, decade by decade, what to build. Everything takes years to arrive, so you commit before you can see whether you were right.
- Today's grid is the residue of old decisions
- Choices that were correct at the time, and their bill
- Emissions accumulate; they do not reset
For teachers
Grid Balance issues assignment codes. Hand one out and every student plays the identical day — the same weather, the same failures, at the same minute — so results can honestly be compared. Students hand back a result code carrying their score and the shift it came from.
No accounts, no logins, no student data collected. Everything runs in the browser.
- MS-PS3 / HS-PS3 — energy
- MS-ESS2 — Earth's systems
- MS-ETS1 — engineering design
- HS-ESS3 — resources and sustainability