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Slideshow: Green Attitude
San Diego's High
Performance Schools
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The Business Case for Energy Efficiency
San Diego's High Performance Schools
by Barbara Crane
In 1997, the San
Diego Unified School District (SDUSD)
adopted an ambitious program of energy efficiency (see
accompanying article).
It was a bold move that has saved the district at least $75 million
dollars in energy costs since 1997. The district took further "green"
steps in 2003 by adopting Collaborative for High Performance Schools
(CHPS)
building standards.
CHPS maintains "scorecards," or lists of criteria that address energy and
environmental design. Points are awarded for a wide array of
environmentally friendly factors in six categories, such as providing a
significant amount of natural daylight and ventilation, good acoustics,
utilizing sustainable building materials, recycling construction waste and
a host of others. Presently, new SDUSD schools are scoring in the range of
38-46 points, well above the basic CHPS certification level of 32 points.
Building schools to meet CHPS criteria became district policy after San
Diego voters passed
Proposition MM, a taxpayer-funded bond
measure in 1998. Proposition MM provided $1.51 billion, of an estimated $4
billion, necessary for modernization projects at 161 existing schools and
construction of 12 new and 3 completely rebuilt schools. Of these 15
schools, 14 are CHPS certified (the first school, which opened in 2001,
preceded the CHPS requirements). Twelve will have opened to students as of
fall 2007; the remaining three are expected to open in 2008 through 2010.
"The district has had building standards since the mid 1970s that
addressed…the use of durable, long lasting materials in our schools," says
Jim Watts, SDUSD's director of architecture and planning. "In recent
years, we've added requirements for buildings to be energy efficient and
to exceed
Title 24. We already had a lot of
CHPS criteria in our standards but these were not specifically
articulated."
In 2005, SDUSD accepted a $25,000
California Energy Commission grant award allowing the district
to hire a consultant to review existing specifications and recommend
changes so that CHPS criteria could be incorporated wherever possible.
Designing a school to meet CHPS requirements is not necessarily more
expensive than a traditional school, says Stacy Strand, an architect with
HMC Architects, which designed Cherokee
Point Elementary School.
David Ruhnau, architect and partner with
Ruhnau Ruhnau
Clarke, agrees. His firm designed
Herbert Ibarra Elementary. Both schools
are CHPS-certified and came on line in 2005. "We have found that our
conventional school designs generally meet the minimum CHPS standards."
Ruhnau says. "The question we face is more about the desire of the
individual school district and whether they have the political/financial
desire to reach for further sustainable measures."
For Cherokee Point, Strand investigated making use of the site's 20-foot
grade difference to insulate and cool the buildings by using one side of
the building to retain the earth. The retaining wall design had to be
abandoned when construction costs proved too high. "The design/build
process, which the district used for Cherokee Point Elementary, considers
only first costs," Strand says. "We had a very tight budget exacerbated by
the rapid increase in materials costs facing the construction industry at
the time, which meant we couldn't incorporate the additional energy
savings ideas that may have accrued from using lifecycle costing."
However, his firm found many ways to make the school energy
efficient. They used light fixtures that minimized energy use, including
efficient
T-8 lamps in all the classrooms
and indirect lighting for student comfort.
In larger spaces like the multipurpose room, they used
metal halide fixtures.
Another (literally) green feature: the design called for a large expanse
of asphalt for the play area. The architects incorporated extensive
landscaping in the middle of the play area to provide shade and relief to
the students.
Located inland in an older neighborhood in southeast San Diego, Cherokee
Point Elementary is near the boundary that delineates SDUSD schools
approved for air conditioning from those that are not. "Our challenge was
to come up with every idea we could to introduce natural ventilation to
cool the buildings," Strand says. "On the second floor we raised the
ceilings and provided operable windows to allow warmer air to escape from
the top. We used large overhangs to the south and west to control heat
gain. We also maximized the amount of insulation."
Staff at the district level are also working to reduce the new schools'
energy profiles. Evan Leslie, SDUSD facilities system project engineer,
has worked towards placing
central plants-far more efficient than
installing individual units for every classroom-in the new schools.
Finding that the local design and contractor environment wasn't conducive
to implementing central plants, he went to larger package units placed at
strategic points on campus that can feed from three to ten or more
classrooms. "A smaller package unit would have to be replaced in 10 to 15
years. A well-maintained larger system can last 30 years or more," says
Leslie.
The school district received grants from
San
Diego Gas & Electric in a
Public Utilities Commission-directed program to offer
reimbursements for additional costs to make new construction greener. It
also qualified for funds under Title 24 by exceeding energy efficiency
minimums.
"Energy efficiency in the new schools paid for itself," Leslie says. "A
lot of schools don't recognize the ability to recoup the costs of energy
efficiency, because they don't apply a business model to the selection of
options available to the district. If you look at the investment and
savings carried over the years, you can make a very good case that the
schools are not only energy efficient but also easier to maintain."
With the new schools nearly completed and Proposition MM dollars nearly
spent, SDUSD is getting ready for its next capital program, which will pay
for modernizing existing schools.
"We're now integrating CHPS requirements more specifically into our
standards," Watts says. "At this point, our district is in a period of
declining enrollment, so we'll be more heavily involved in retrofitting
and modernization. We're going to look at how we can incorporate CHPS into
our modernization efforts."
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