Utility-Scale Solar Array Calculator

Reading a utility solar plant's numbers

Utility solar carries two nameplates. MW-DC is the module capacity in the field; MW-AC is what the inverters can export, and it's the figure that matters to the interconnection agreement. The DC/AC ratio between them — typically 1.2 to 1.4 — is deliberate overbuild: it flattens the production curve and accepts some midday clipping in exchange for more energy in the shoulders of the day, when it's usually worth more.

Production is quoted as specific yield (kWh per kW-DC per year — roughly 1,400 in cloudy markets, 1,900+ in the desert Southwest) or as capacity factor against the AC rating, generally 22–32% for single-axis trackers. Land runs 4–7 acres per MW-DC depending on tracker pitch and terrain, which is why a 200 MW project is a four-figure-acre land assembly and why site control is where development risk concentrates.

For data center developers the sobering line is the last one: divide annual GWh by 8,760 hours and a 200 MW-DC plant is equivalent to only about 35–40 MW of continuous supply. Solar alone can't carry a 24/7 load — which is exactly why utility-scale projects increasingly pair the array in this calculator with the storage in the BESS sizing tool next door, and why "matched" clean-energy claims deserve a close read of the hourly math.