Symbol P_d
is part of the quantity the equation computes from the expression on the right.
Read this term in its guide →Published equation contexts
Why this formula appears here
The second confusion is with capacity factor . Power density is an area-normalised output rate; capacity factor is a time-normalised one. They multiply rather than substitute. Writing energy generated as E over a period t across area A , with nameplate capacity C and capacity factor f : . The first factor, capacity density , is a siting and engineering question; the second is a resource and dispatch question. Miller and Keith’s US measurements make the separation visible: they report 2016 mean capacity factors of 32.9 per cent for wind and 22.1 per cent for solar, with 90th-percentile values of 43 and 27.5 per cent, alongside power densities that are not in the same…
Read the representative guide
Symbol E
E occurs above the fraction bar. The numerator is divided by the entire denominator below it.
Read this term in its guide →Symbol A
A occurs below the fraction bar. The quantity above the bar is divided by this expression; zero is excluded as a denominator.
Read this term in its guide →Symbol t
t occurs below the fraction bar. The quantity above the bar is divided by this expression; zero is excluded as a denominator.
Read this term in its guide →Denominator: At
The complete quantity below the fraction bar; it must be nonzero for this division.
Read this term in its guide →How to interpret it
With a fixed numerator, increasing a nonzero denominator reduces the fraction. Read it with the definitions, units, and assumptions supplied by the article.
Research cited beside this formula
Published contexts (1)
A symbol can carry a different meaning in another article. Each occurrence keeps its own guide and term definitions.
Equation 6 · Energy & Civilization
Power Density and What It Permits
This equation states an equality: the expressions on both sides have the same value under the article’s assumptions.
The second confusion is with capacity factor . Power density is an area-normalised output rate; capacity factor is a time-normalised one. They multiply rather than substitute. Writing energy generated as E over a period t across area A , with nameplate capacity C and capacity factor f : . The first factor, capacity density , is a siting and engineering question; the second is a resource and dispatch question. Miller and Keith’s US measurements make the separation visible: they report 2016 mean capacity factors of 32.9 per cent for wind and 22.1 per cent for solar, with 90th-percentile values of 43 and 27.5 per cent, alongside power densities that are not in the same…