Solar Panels © Sergiogen - Fotolia

Is Solar Unsustainable?

We can remain hopeful about the future of solar power, provided we deal with its worrisome side effects.

As greenhouse gases go, hexafluoroethane (C2F6), nitrogen trifluoride (NF3) and sulfur hexafluoride (SF6) are about as obscure as a high school band at the Rolling Stones concert of atmospheric warming.

Nobody’s suggesting they deserve top billing, but Ozzie Zehner of the University of California thinks these three GHGs are worthy of at least a little infamy.

As greenhouse gases go, hexafluoroethane (C2F6), nitrogen trifluoride (NF3) and sulfur hexafluoride (SF6) are about as obscure as a high school band at the Rolling Stones concert of atmospheric warming.

Nobody’s suggesting they deserve top billing, but Ozzie Zehner of the University of California thinks these three GHGs are worthy of at least a little infamy.

The gases in question are all products of the solar cell manufacturing process. These GHGs are also – and here’s the disturbing part – an average of 17,000 times more potent than CO2.

Zehner concludes that solar power is not as environmentally friendly as we thought: “If photovoltaic production grows, so will the associated side effects.”

It may be premature to purge the sting of betrayal by smashing our solar panels in an Office Space-inspired rampage. Solar power, how could you? Well, too much of anything – except maybe broccoli – will make you sick, and even renewable energies are no exception to the rule.

Having staggered the renewable energy community with an unexpected left hook, Zehner exercises restraint on the knockout punch. “Alternative energy is not a free ride, just a different ride,” he says. “My critique comes when you take a step back and look at the technology in context.”

This may sound like a damning indictment, but it’s not, really. We’re just accustomed to the idea that renewable energy is the diametric opposite of everything represented by fossil fuels: clean, safe and sustainable. The reality is still bright, just somewhat less utopian.

The context to which Zehner refers – and the source of his restraint – is that solar is a valuable technology with a few flaws to be amended. Even taking into account the effect of the aforementioned obscure greenhouse gases, a lifecycle analysis by the National Renewable Energy Laboratory (NREL) found that solar photovoltaics are responsible for an average of 45 grams of GHGs per kWh, in contrast to 1001 grams for coal.

Sulfur hexafluoride, according to one NREL analyst, accounts for a very modest two-tenths of one per cent of the greenhouse gas problem, although a US National Oceanic and Atmospheric Administration (NOAA) study notes that concentrations are rising exponentially – a trend one would expect to continue if we maintain a high rate of solar cell production.

Nevertheless, it’s difficult to extrapolate the course of the solar industry too far into the future. The rate of innovation in this field tends to outpace bold predictions. For example, a transparent film with the potential to turn windows into solar panels is one of the latest ideas to reach the testing phase. Flexible nanowires from research done at McMaster University are also being tested. There’s no reason to think that C2F6, NF3 and SF6, despite their charming names, won’t become redundant with continued industry advancement.

If we cover the world in solar panels, there’s bound to be at least one or two problems or complications. Maybe a material shortage; maybe the massive reflection of light will blind passing aircraft pilots – I’m being glib, but my point is that some imperfections are absolutely inevitable, which is why we should also be diversifying our strategies. That doesn’t mean we should be dejected about the potential of solar cell technology. It means we should continue doing our best to refine it.

Stu Campana is an international environmental consultant, with expertise in water, energy and waste management. He is the Water Team Leader with Ecology Ottawa, has a master’s in Environment and Resource Management and writes the A\J Renewable Energy blog. Follow him on Twitter: @StuCampana.