Whats frustrating is reading
Whats frustrating is reading the baseless muck raking renewable energy is subjected to. Phrases such as "in fact, if I remember correctly, many studies show" is nothing but a weasely attempt to try and justify the rest of your comments as being evidence based. Can you link some of those many studies or a basis for any of your claims for that matter?
Here are a few studies to back up mine, their findings are that it takes between 1 and 3 years to pay back the energy used to create solar panels and that ground mounting adds ~1 year of additional embodied energy.
E. Alsema, “Energy Requirements and CO2
Mitigation Potential of PV Systems,” Photovoltaics
and the Environment, Keystone, CO.
Workshop Proceedings, July 1998.
R. Dones; R. Frischknecht, “Life Cycle Assessment
of Photovoltaic Systems: Results of Swiss
Studies on Energy Chains.” Appendix B-9.
Environmental Aspects of PV Power Systems.
Utrecht, The Netherlands: Utrecht University,
Report Number 97072, 1997.
K. Kato; A. Murata; K. Sakuta, “Energy Payback
Time and Life-Cycle CO2 Emission of Residential
PV Power System with Silicon PV Module.”
Appendix B-8. Environmental Aspects of PV Power
Systems. Utrecht, The Netherlands: Utrecht
University, Report Number 97072, 1997.
K. Knapp; T.L. Jester, “An Empirical Perspective
on the Energy Payback Time for PV Modules.”
Solar 2000 Conference, Madison, WI, June
16–21, 2000.
W. Palz.; H. Zibetta, “Energy Payback Time of
Photovoltaic Modules.” International Journal
of Solar Energy. Volume 10, Number 3-4,
pp. 211–216, 1991.
So essentially even taking utility ground mount systems into account numerous studies show the time to energy payback is between 2 and 4 years, this summary article's claim of around 2 years to payback the embodied energy seems within the ballpark.
No I don't think it is misleading for your kid's school not to include a complicated technical discussion about embodied energy when the reality is that the system will continue generating for ~25 years after the embodied energy has been repaid.
No rooftop vs ground mount systems don't have vastly different paybacks, ground mount adds ~30% to the embodied energy. considering we have a mix of both discussing solar as a whole seems perfectly appropriate.
It is not surprising that in the late 1990's when solar panels were still a high priced boutique item that really only made sense in remote off grid applications where they displaced the need to use and transport expensive diesel for generators that no large manufacturing plants were powering themselves with their own solar panels, they would have been far more valuable sold then offsetting cheap grid power. In the 1990's solar panels averaged about $7 per watt for the modules alone, in 2012 we cracked $0.70 for the modules.