The ornamental design for a solar-powered exhaust fan, as shown and described.
FIG. 1 is a top, side perspective view of the solar-powered exhaust fan;
FIG. 2 is a bottom, side perspective view of the solar-powered exhaust fan;
FIG. 3 is a side elevation view of the solar-powered exhaust fan, with the other sides being a mirror image thereof;
FIG. 4 is a top plan view of the solar-powered exhaust fan; and,
FIG. 5 is a bottom plan view of the solar-powered exhaust fan.
The broken lines shown in FIGS. 2 and 5 are for the purpose of illustrating portions of the solar-powered exhaust fan that form no part of the claimed design.