So looking at the amount of CO₂ created by producing solar panels is one thing, but there’s also the idea that the amount of actual energy used to create the panels somehow larger than the panels will be able to pay off.  In reality, this thought is actually very similar to the CO₂ question addressed in my previous post; since CO₂ is just a byproduct of energy production (be it a gasoline engine or a coal fired power plant) you can figure out how much energy it takes to produce a given array.  

Coal power plants produce roughly 2kWh per kg of coal burned.  Thus, we can quickly figure (using the highest 350kg CO₂/m² number described in the CO₂ offset post), that our panels used the equivalent of 4,472 kg of coal to make (37.44 m² of PV Panels * 350kg CO₂/m² to make them / 2.93kg CO₂ created per kg of coal burnt) or the equivalent of 8.94MWH of electricity.  Our set of panels should produce close to 7MWH/year so they should be net positive in December if this fall is similar to last year’s.  This would be 16 mos. after installation.