A Dark Side of Solar Power

The harshest criticism for fossil fuels has always been the horrible effect they have on the environment. Not only does retrieving the resource (coal, petroleum, natural gas) do irreparable damage to landscapes and ecosystems, but transporting it can be quite dangerous. And once the fuel has been spent, harmful byproducts clog the atmosphere and have far-reaching effects that scientists have only recently begun to quantify.

You know this, and I know this. And I know that you know that we all know this. This isn't going to be a recital of facts we know, ya know? But what about the negative environmental impacts our cultural shift to renewable energies, namely solar power, produce? There is a side to solar (PV) power that's rarely considered and not well understood.

Energy Payback Time (EPBT)

EPBT is the amount of time it takes a solar panel to collect the same value of energy that was expended in the panel's creation. It used to be that panels virtually never recaptured the amount of energy which was needed to create them, but that belief faded in the 1990s as the technology improved.

A significant amount of energy is spent producing, processing, and purifying materials for PV panels, as well as for the manufacture, transportation, and installation of the panel. The mathematical formula(.pdf) for determining the EPBT looks like this:

Rather than break down figures for areas with my limited text space, I'll just spoil the conclusion: the effectiveness of solar panels is severely affected by material efficiency and the location of the panel. In most of the United States, it takes almost two years before the panels begin to reduce emissions. At what latitude do solar panels stop making sense?

Environmental Waste

Not surprisingly, China has been the leading manufacturer of PV panels worldwide by nearly fourfold. Despite this robust production rate, they're only second in PV power production (18,400 mW compared to Germany's 36k mW). What gives?

Frankly, China doesn't care about its environment and has little oversight on how companies dispose of industrial waste. And in consideration of the profit the industry is making, what regulations do exist are overlooked. U.S.-based PV panel manufacturers have a hard time disposing of toxic materials used in the production process. Chinese companies don't have the same difficulty, choosing to bury chemicals or flush them in public waterways. The result is a panel which was cheaper to produce and ship abroad.

Really, we're just burying the problem someplace else, hoping that a super-solution from future geniuses materializes in the meantime.

Wildlife Impacts

The Ivanpah solar plant in utilizes 174,000 heliostats to reflect sunlight onto a centralized solar tower. The tower collects the sunlight, transfers it to heat, and boils water to begin the electricity production process. The plant is located in the Mojave Desert, away from population centers.

Human population centers, at least. While the imagery of a desert solar plant probably conjures images of dust and tumbleweeds, the area where the plant lives is much more lush than you might expect. When the plant was first announced, it incited considerable backlash because it was building on habitat that belonged to the endangered desert tortoise. The plant's construction was ultimately changed to help curtail its effects.

Now that the plant is up and running, an unforeseen consequence has occurred: an excessive number of bird deaths. Birds are lured to the area by insects or migration patterns, but once in the vicinity of the plant they're almost assured a hellish death. Estimates of up to 28,000 bird deaths a year have been attributed to the concentrated solar arrays, which blind and even ignite birds midflight. Officials are considering how to proceed with a megawatt and mega-money facility that may drive the extinction of entire species on its own.

The point isn't that solar power is harming our environment. Without a doubt, nearly any energy harvest strategy will conclude with negative environmental effects. But it shows that a long, long road of development must be traveled before our technology creates the sustainable utopia we envision. For now, we should probably maximize the efficiencies of the energy sources we have.