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It remians to be seen if the net-zero energy buildings are economical in first cost compared to the nonnet-zero buldings and how much more energy was consumed in producing the additional materials and equipment to manufacture the on-site renewable energy products including the installation cost of these equipment to gain net-zero energy.
Your definition of Net-Zero buildings vs. Carbon Neutral buildings is a bit confused. Here are the concepts as I have seen them explained. A Net-Zero Energy building produces as much energy as it uses in a year. It does not have to be off the grid to be considered Net-Zero. Determining what it means to be Carbon Neutral is much more complicated. As far as I can tell, claiming that something is Carbon Neutral means that it does not create net greenhouse gas emissions. Just because energy is created at the site of the building does not make it Carbon Neutral -- for instance, if you burn something in a turbine to create electricity, you are sending CO2 molecules up into the air. On the other hand, if your grid electricity from the local utility is provided by wind and hydro, it may create almost no CO2 (hint: nothing is burning). This is an interesting topic that will have a huge effect on all of us, and on many generations to come. Thanks for featuring these ideas in your article.
Just running some numbers, it seems the Net Zero investment option is indefensible in terms any CFO would understand. If we generously assume $7/watt installed, 1500 solar multiplier, a very tight building using total energy roughly matched to the output of the system, and 10 cents per Kwh, the payback would be 46.7 years. To sell this to any CFO, you have to count on a 6X increase in that power rate to drop the payback to a reasonable number. Is that what the president meant by "necessarily skyrocket?" Who really wants that?