So far, my 18 panels have prevented me from spewing an “extra” 445 kg of carbon into the atmosphere.  I know that everyone talks about carbon, but today I’m focusing on the mercury I’ve avoided, because I like fish.  Eating them, that is.  Okay, I also have them as pets, and have even cried real tears at the funeral of a favorite.  So, my relationship with fish is, I suppose, morally ambiguous.  But that doesn’t mean I think we should poison them, or ourselves.  I live near the Chesapeake Bay and my father loves to fish.  He often catches striped bass which are so high in mercury you could use one as a thermometer if it wasn’t so big.  So, when he offers me these delicious filets, I only take about one tenth of what I really want to eat because I’m afraid of, y’know, poison. 

Where does this mercury in my fish come from?  Each kilowatt-hour of electricity you (and I) burn releases 0.023 milligrams of mercury into the atmosphere.  A certain amount ends up in the ocean (read this article if you want to learn how).  By producing 744 kWh of energy, my solar system has avoided 17.11 milligrams of mercury release.  I like to translate numbers into units we can really understand, but I’m having trouble converting mercury because it’s hard to say that by cutting down on mercury in the atmosphere I’ve saved such-and-such number of kids from neurological disability.  So exactly what HAVE I done?

Maybe mercury poisoning can best be illustrated by turning the “what if everyone did it?” argument upside down.  This is the favorite chastisement of park rangers:  Sure, you only want to pick one flower, but what if everyone picked just one flower?  What if we imagine that everyone in the world did a good thing, just for once, and cut their consumption of electricity in half?  (And now might be a good time to ask all the libertarians out there to take your flame-throwing cursor out of my comment box.  I’m not preaching, just dreaming.)  Over the last three years, our household has cut our kilowatts in half with a combination of conservation and solar panels.  I’m not necessarily pushing panels – because that wasn’t the whole story for us – there are lots of ways to reduce.  Conservation, geothermal, wind, passive solar, insulation, you name it.  Truly, I am a free market spirit.  But if everyone did it, there would be 1,250 fewer tons of mercury released into the atmosphere. 

That won’t entirely clean up your fish dinner, I’m sorry to report.  Over half the mercury in the atmosphere is released by natural degassing from the land and ocean.  But, still, half of the world’s electricity accounts for about 20% of the world’s mercury.  So while your fish may not end up being mercury free, reducing the poison by 20 % just might bring that scary sushi back down below the FDA’s approved level of less than 1 part per million.