Thinking Past Stovepipes: Solar Electricity on Roof and Classroom

Solar panels cover my rooftop and generate about 80 percent of my household's electricity use.  My house, of course, has numerous other "energy cool" elements (solar light tubes, high-efficiency fireplace insert, insulated whole-house fan, efficient appliances, etc...) but those solar panels generate 99 percent of the initial questioning about the house and my home's energy issues.  While frustrating, in a way, since solar pv is far less cost (and environmentally) effective than energy efficiency investments, there is a (legitimate) positive spin on this: The solar panels serve as a gateway to opening conversations about home energy use and enables education.

So too is the case for solar panels on and around educational facilities. If we care solely about EROEI (energy return on energy invested), there are many (MANY) things to do before putting up on solar panels. If, however, we care broadly about EROI (Educational Return On Investment), then the solar panels begin to make sense as part of an educational energy investment.

In the typical school system, the instructional and infrastructure staffs are barely on speaking terms short of communication about things like: "The water fountain is broken and needs fixing."  
These staffs interact, but it is a very functional interaction -- the infrastructure (facilities) staff is a service with the responsibility of making sure the building is working and hear (loudly and quickly) when there is a problem.

This gap misses a major opportunity of space to improve the educational process, and solar panels are a poster child of that opportunity.

There are drives for STEM (science, technology, engineering and mathematics) education.  When working on STEM programs, educators look for "systems" to study. Rarely do these educators think about the very building they reside in (work in) as what it is: a rather complex system-of-systems, with heating, ventilation and air conditioning (HVAC), plumbing, electricity, with a variety of building materials, that has complex interactions of impacts from the sound and air quality, temperature, lighting, pollution loads and otherwise. When elementary school science teachers ask me for good ideas for field trips, my typical response: "Have you visited your own school?"

Solar panels provide a gateway opportunity for building and energy system integration into the classroom. And, that "gateway opportunity" is what makes this a truly viable opportunity -- not on ROI nor necessarily EROEI terms, but on EROI.

When it comes to financial return on investment (ROI), in many communities around the world, putting up solar panels has a direct financial return (putting aside tax benefits and otherwise) counted in a few decades. Solar power, without some external financial support, is fast gaining ground, but it simply isn't the winner in a straight financial shoot-out in much of the developed world's electricity markets at this time. Yes, solar beats oil-based fuel and is tremendous for addressing peak urban air conditioning demand, but (without pollution charges) it doesn't (yet) price out natural gas or hydropower or, sigh, coal.

And, as discussed above, when it comes to EROEI, it's much better to invest in insulation, energy control systems, more efficient HVAC systems, skylights and a rash of other energy efficiencies which will have a greater bang for the buck on EROEI.

However, when it comes to EROI, solar electricity might be the most stellar opportunity in the educational energy market space.
  • Visibility
    • Solar panels are highly visible.  Students, teachers, parents, the community will be aware of them.
    • The school lobby could have a visual display -- constantly updated -- as to electricity production (current, cumulative over various periods -- day, month, year, lifetime) and this would also be available via the web.
    • The solar panels will spark discussion about energy issues ... as it does with my home.
  • Ease of integration into the educational curriculum
    • The reporting systems make the data easily available to teachers and students for use in the educational system.
    • A solar electricity system is incredibly easy to integrate into the educational environment. For example ...
      • Kindergarteners could learn seasons and whether there is more solar electricity / more sun in winter or summer.
      • Elementary school students could use it for learning arithmetic, how to do distribution plots and other development of basic math scales.
      • Middle Schoolers could calculate the distribution curves of solar electricity generation across time of day and across seasons, with analysis about variability and predictability. This could include, for example, taking multiple weather reporting services predictions and analyzing which correlated best with predicting actual electricity output.
      • Advanced High School students could analyze life-cycle costs per solar kilowatt hour -- in dollar, energy, and environmental impact terms -- and do comparative analysis for other electricity generation and energy efficiency options.
  • Electricity production
    • Oh, by the way, remember that those solar panels are generating electricity -- which has a value even if that value is a fraction of the educational value for the school system.

In my area, each watt of solar costs roughly $4 to put on a roof (down from $6 way back in 2010 ... e.g., the price is rapidly falling).  A $50,000 investment would, therefore, put a roughly 12.5 kilowatt solar pv system on the roof.  That system would produce in the range of 16 megawatts per year of electricity.  As the school system pays a discounted electricity price of about $80 per megawatt, that would mean $1,280 of electricity value per year or just under 40 years of straight payoff (likely reduced to 15-20 years or so if peak charge reductions are accounted for) for putting solar on the roof (assuming away any tax or other benefits from the equation).  Hmmm, this doesn't sound good in ROI or EROI terms.

However, ask yourself: How much does a school system pay for textbooks?  How much should the school system assess the educational value of those rooftop panels, which will be there 25 years or longer?  A 1,000-student elementary school might have over 4,000 students over that time period.  Will the average student -- through addition classes and otherwise -- gain $50 of value through those panels?   If that number is anything close to reasonable, the EROI (educational return on investment) is something like 4 to 1 the system's costs, even without considering the value of the electricity generation.

Joe Plummer, CEO, Three Birds, The Educational and Inspirational Value of Renewable Energy. "The project showed me that the value of solar technology was not always financial or even environmental. The educational and inspirational value far outweighed anything else."