About a year ago I was excited to learn that Lamar advertising was upgrading its billboards in Florida with solar panels. I thought that there might be some work in it for local Florida solar contractors. Unfortunately, that never happened. It gets worse…
I was again excited to see that Fafco Solar’s billboard on US 41 in Fort Myers had been upgraded with solar panels, so I stopped by to check it out. It’s not what I expected. I thought the billboards would have a grid-independent solar energy system with battery backup. It turns out that what is installed is simply a four-panel grid-interactive solar energy system. The system utilizes four 230W solar modules and two [now discontinued] Enphase D380 microinverters. The system is capable of producing 760 AC watts, and approximately 1,300 kilowatt-hours annually (equivalent to approximately $150 in utility electricity).
Normally I would be elated to see anyone install a solar energy system, but this is the epitome of green-washing and an example of a totally impractical use for solar energy.
There are a few good reasons to use solar energy to power a billboard. The first is to be independent from the grid, making the lighting and advertisement rotation motor operate during utility outages. The second is to eliminate the need for grid power in remote locations, like along Interstate highways where it may be costly to install utility poles and meters. Tangential reasons are to reduce operating costs and produce green energy. This is where my concern lies.
If you want to reduce your energy footprint or operating costs, the best way to do it is in the most economical fashion possible. That is, produce the most energy for the lowest investment. The manner in which these solar panels are installed is very expensive, requiring a lot of steel to make a hardy wind-resistant rack. It also requires fixed costs like permitting and interconnection hardware. The better choice would have been to install solar panels at the company’s headquarters in a more efficient ground or roof mounted system. For example, instead of installing four panels on 1,000 billboards, it is far more efficient to install a system with 4,000 solar panels in the same location. The end result would be the same. There is no benefit to having these solar panels colocated with the billboards.
Distributed energy production systems like small grid-interactive solar energy systems are generally a good thing, and I support the concept fully. However, there comes a point at which the marginal benefit is so small that you have to ask yourself, “is this practical?” In this case, the answer is clearly NO!