Place wind, solar, gas, nuclear, hydro and battery blocks on the map, then see 8,760 simulated hours: duck curve, lost-load hours, cost per MWh and CO2.
Tap a map site with a tool to add a block (max 4 per site); tap with another tool to replace; Erase removes. Hydro only fits the two river sites (S11, S12).
Sweep: how do lost-load hours, curtailment, cost and CO2 respond when you keep adding solar to the current mix? The gas search keeps your other blocks and finds the smallest gas fleet that meets the common 2.4 h/yr (one day in ten years) criterion.
A synthetic but physically shaped year (8,760 hours) is built from weather and demand profiles; every hour the generators are dispatched in merit order and the books are balanced. Weather is generated, not measured: treat the numbers as a teaching model, not a forecast for any real utility.
The 1.1 factor stands for a DC/AC ratio above 1 with ~85 % performance ratio. Daily cloudiness is an AR(1) process. Latitude changes day length and winter output.
Power scales with v3 (kinetic energy flux 1/2 rho A v3) until the turbine is rated. Real wind farms also have wake losses and a spatial spread that smooths output; both are ignored.
This is a simple rule-based dispatch, not an optimiser: it neither pre-charges storage from gas nor holds storage for a forecast peak, so it understates what a real operator could do. Transmission limits, ramp rates, reserves and frequency are ignored (see the separate frequency-balance lab for those).
With lots of solar, midday net load collapses while the evening peak stays. The 3-hour ramp is the largest rise of net load within 3 h; dispatchable plants must follow it.
Costs are round, illustrative overnight-capex values (US$/kW: wind 1,300; solar 900; gas 900; nuclear 7,000; hydro 3,000; storage 300 + 250 per kWh), not quotes. Gas fuel = 7 MMBtu/MWh x gas price. CO2 uses lifecycle medians in t/MWh (gas 0.49, solar 0.048, hydro 0.024, nuclear 0.012, wind 0.011). The value of lost load ($10,000/MWh) is reported separately and not added to the cost.
Loss-of-load hours (LOLH) counts hours with unserved demand above 0.5 MW. A common planning target is about 2.4 h/yr (one day in ten years). One weather year is a small sample: switch the weather year to see how much the answer moves.
The page rechecks the dispatch with identities it does not use to compute it: the hourly energy balance, a compensated annual sum, the storage energy ledger, and two closed-form cases (flat load with a gas fleet, where cost and CO2 follow from algebra) plus a sun-geometry integral (the sum of sin(elevation) over an equinox day at the equator equals 24/pi).