The inherent inefficiency of the three-light traffic signal is clearly demonstrated in this proposal for a two-light LED system, which produces the same three colors in one enclosure by combining red and green. Unfortunately, it still can't melt snow.

Two-Color LED Traffic Light Has One DrawbackS

[Industrial Design]

Two-Color LED Traffic Light Has One DrawbackS

[Industrial Design]

Two-Color LED Traffic Light Has One DrawbackS

[Industrial Design]

Two-Color LED Traffic Light Has One DrawbackS

[Industrial Design]