"In Europe companies must buy vouchers to emit CO2, which trade at around twenty to forty dollars per ton. Most analysts expect American permits to stabilize on the open market somewhere below thirty dollars per ton. Today’s solar technologies would compete with coal only if carbon credits rose to three hundred dollars per ton. Photovoltaics could nominally compete with natural gas only if carbon offsets skyrocketed to six hundred dollars per ton.
It is difﬁcult to conceive of conditions that would thrust prices to such stratospheric levels in real terms. Even some of the most expensive options for dealing with CO2 would become cost competitive long before today’s solar cell technologies. If limiting CO2 is our goal, we might be better off directing our time and resources to those options ﬁrst; solar cells seem a wasteful and pricey strategy.
Unfortunately, there’s more. Not only are solar cells an overpriced tool for reducing CO2 emissions, but their manufacturing process is also one of the largest emitters of hexaﬂuoroethane, nitrogen triﬂuoride, and sulfur hexaﬂuoride. Used for cleaning plasma production equipment, these three gruesome greenhouse gases make CO2 seem harmless. As a greenhouse gas, hexafluoroethane is twelve thousand times more potent than CO2, is 100 percent manufactured by humans, and survives ten thousand years once released into the atmosphere.
Nitrogen triﬂuoride is seventeen thousand times more virulent than CO2, and sulfur hexaﬂuoride, the most treacherous greenhouse gas, according to the Intergovernmental Panel on Climate Change, is twenty-ﬁve thousand times more threatening.
The solar photovoltaic industry is one of the leading and fastest growing emitters of these gases, which are now measurably accumulating within the earth’s atmosphere. A recent study on nitrogen triﬂuoride reports that atmospheric concentrations of the gas have been rising an alarming 11 percent per year."