Bob Heinz

Bob Heinz, marketing manager for Addco Manufacturing Co. agrees, "Solar will most certainly replace diesel.The diesel market may not exist one year from now."

Solar-powered signs posses many advantages over diesel- or gasoline-powered signs.Diesel signs use an engine and a generator to produce its power; thus requiring more manpower in refueling, as well as fixing break-downs and performing maintenance to the engine and generator.Solar, on the other hand, requires a minimum amount of maintenance.
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Heinz explains, "Overcast weather is not a factor because enough sunlight gets through to allow the system to charge the batteries."Addco's model also allows the user to tilt and rotate the solar panel in order to receive the full benefit of the free energy from the sun.In addition to recharging the batteries with the sun, solar signs also can be charged by plugging them into an AC outlet.

Some manufacturers provide fail-safe modes for their solar signs in case of a power failure.American Electronic Sign, for example, provides a retroreflective flap that displays a preprogrammed default message in the event of a power failure.This flap can also be used to conserve energy stored in the batteries.