That depends on your latitude, how dear land is, and how close to breakeven your application is.

For a lot of applications, panels are so goddamn cheap now and breakeven happens so fast that "Just buy twice as many panels" is the best solution to any problem that doesn't involve land area. Winter production in a snowy/leafy climate at a latitude tilt, though, is the exception to the rule; Production is so impaired without regular maintenance that twice as many panels is not very helpful. But set those panels vertical, at a range of orientations, and snow/leaves stop being an issue, you get sizable exposure with the sun low on the horizon, the maintenance requirement goes away, and you get an appreciable amount of power earlier in the morning and later in the afternoon, you just don't get quite as much at noon.