Does solar power really use up huge amounts of land?

No. Supplying all of America's electricity from utility-scale solar would take roughly 22,000 square miles — an area already largely occupied by fossil fuel extraction infrastructure: coal mines, gas well pads and haul roads. The difference is the nature of the occupation: a coal mine scars land for a century, while a solar farm can host agrivoltaics, growing crops or grazing sheep beneath the panels.

Critics point at vast desert arrays and argue that solar is eating the landscape. Put on the same scale, the numbers say otherwise: meeting total US electricity demand with utility-scale solar would require about 22,000 square miles, and today's fossil fuel extraction infrastructure — coal mines, gas well pads, haul roads — already occupies land of broadly that order. The real distinction is not area but how the land is used: open-cast mining leaves scars measured in centuries, whereas a solar farm can keep farming or grazing underneath the modules.

The land argument usually travels with the EROI myth — the claim that a solar panel consumes more energy to manufacture than it will ever generate. That may have held in a 1970s laboratory; it has since been disproved. Modern PV systems have an EROI of 10 to 30, meaning that each unit of energy invested in mining, refining silicon and shipping modules returns 10 to 30 units over a 30-year life. Energy payback time is now 1 to 3 years depending on the site's irradiance — a three-year payback on a thirty-year asset is a substantial return in energy terms.

A third objection concerns toxic materials. Manufacturing panels does involve semiconductor-grade chemistry, and thin-film modules sometimes contain small quantities of cadmium or lead — but in minute proportions, sealed inside tempered glass. By comparison, coal plants emit mercury, lead and arsenic directly into the atmosphere or pile them into large coal ash ponds that can leach into groundwater. The toxicity burdens are not comparable.

Finally there is a resource dimension that is often overlooked: water. Conventional thermal plants — coal, gas and nuclear — are essentially giant steam machines and need billions of gallons of cooling water. Solar PV uses almost none while operating. In an era when water scarcity is an increasing driver of conflict and economic loss, that is a major strategic advantage. The notable exception is concentrating solar power (CSP), which also runs steam turbines and can consume as much water per MWh as a coal plant — while its best sites are the driest deserts.

Supplying all of America's electricity from utility-scale solar would take about 22,000 square miles — land that is already, for the most part, occupied by fossil fuel extraction infrastructure: coal mines, gas well pads and haul roads.

This question is covered in depth in The Full Spectrum Every Energy Source Explained — A Singapore Perspective，第七章 7.6