October 26, 2010

San Ramon Schools Turn Parking into Solar Power

Local high schools will soon see their parking lots shaded by solar arrays, thanks to a $23 million dollar contract the SRVUSD recently signed with SunPower, a San Jose-based company. Though the agreement was singed over the summer, the final design meetings are happening this week.

The district has posted (pdf) projections of future energy savings and general fund benefits: under the conservative estimates, it expects to save $27 million in energy costs over the first seventeen years. Estimates also peg the debt incurred (via low interest Qualified School Construction Bonds*) to be payed off in 17 years, bringing the low-ball, 25 year boost to the district's general fund to $11 million. The optimistic projection tallies that number at $30 million, based on higher assumed increases in PG&E rates and a lighter debt load.

*QSCBs are part of the American Recovery and Reinvestment Act of 2009, which authorizes these special low-interest bonds for schools seeking to improve infrastructure. Fascinating to see how that stimulus is trickling down.

Investing in infrastructure that cuts fixed costs seems like a no-brainer, but especially for any landowner not expecting to relocate. Colleges, universities, and high schools spring immediately to mind. I wonder if anyone has a model for installing solar arrays in commercial parking lots, like those at regional shopping malls. What I don't know is what incentives the developer/owner would need to make such a retrofit attractive--if each individual tenant pays its own utility bill, then the incentive is small, spread thinly across all stakeholder, and probably stymied by the unusually deliberate coordination and mobilization the task would require. This is conjecture, because I do not know how such arrangements would work ... if a central body pays collective utilities, the incentive to go solar would appear to be much stronger.

Diablo Valley Community College already has photovoltaic arrays on all surface parking lots at its Concord campus. Chevron Energy Solutions, a unit of local business and energy juggernaut Chevron Corporation, partnered with DVC, Los Medanos Community College, and Contra Costa Community College to complete installation in 2008.

Parking lot arrays near the DVC football field

The Chevron press release detailed additional services provided:
  1. a 3.2-megawatt solar power generation system comprising photovoltaic panels mounted on 34 parking canopies in six parking lots at Contra Costa College, Diablo Valley College and Los Medanos College;
  2. high-efficiency lighting and energy management systems installed at CCCCD's three colleges and District Office, as well as high-efficiency heating, ventilation and air-conditioning equipment at CCCCD's District Office; and
  3. high-voltage electrical system replacements installed at Diablo Valley College and Los Medanos College.

The Athenian School, a private college-prep partial boarding school in Danville has also installed a solar array (in the shape of an A, natch) with a slightly different approach. It partnered with Tioga Energy in what appears to be some sort of subcontractor-esque agreement--the solar power purchase agreement (PPA) signed states that Tioga Energy owns, operates, and maintains the system. Tioga sells the solar electricity generated to the school at fixed rates over a 20-year period.

Since PG&E rates will surely increase, and since the arrangement does not require Athenian to invest in a massive capital outlay, using middlemen might make modifications more manageable (alliteration, ftw). I'm assuming that Athenian's monthly savings would be less than if they owned the array, given that Tioga needs to turn a profit somehow, but Athenian is already getting about 50% of its electricity from the investment.

A little further research reveals that Tioga has signed PPAs with the Lafayette School District, five New Jersey school districts, and SoCal's Irvine Unified School District.

1 comment:

  1. One editorial note I didn't make in the post, though it's somewhat implied--the Athenian project would be sweeter if it didn't involve greenfield development. They could have easily used roof tops, like the other PPAs described ... but the appeal of a big solar A cannot be denied, were I a school principal looking for the ingredients to an awesome press release and school landmark. Politics and sexiness matter.

    Other implied point I wanted to state explicitly: parking lot solar arrays are excellent examples of adaptive re-use, retrofits, brownfield development, and probably other buzz words I'm forgetting. Added capacity, no new footprint or habitat degradation, substantial energy savings, as well as shade, shelter, and scale for what are usually the barrenest of urban and suburban expanses.