Roof-Mount Project of the Year: Bishop O’Dowd High School


Oakland, Calif. | 51 kW

Education and renewable energy go hand in hand. The energy revolution we’ve seen the last few decades has come about because of some serious chart 1education and re-education of the public. If humans plan on sticking around awhile, growing an awareness of sustainability is as important today as acquiring skills in math, history and language arts. Bishop O’Dowd High School believes in these principles.

This private school in Oakland, Calif., wants to help create a sustainable environment as part of its mission, with an emphasis on resource conservation, respect and learning from nature. These lessons pop up both in its curriculum and in its operation.

The school has a Center for Environmental Studies, two plant propagation centers and even a director of sustainability on staff. The center has been awarded the highest Leadership in Energy and Environmental Design (LEED) certification possible.

Modules: Trina Solar’s versatile PD05 module 

The school’s overall aim is to reduce greenhouse gas emissions to close to zero by the year 2025. Since the school is located in California, saving water is also hugely important, so the school is cutting its water use by replacing grassy areas with artificial turf or drought-tolerant plants.

“In the Oakland area, the average temperature is mild with the bay influence. Our school was built in 1950 and well designed for the period,” says Dan Malmgren, director of facilities for Bishop O’Dowd. “Embracing technological change, we were an early adopter of projected electronic curriculum, which required a 94 percent light filter window blind to lower the ambient light level, which altered air flow through the windows. At the same time, we remodeled the classrooms and replaced the 60-year-old windows with new high efficiency E-glass, which withholds more heat during the warmer days.”

Bishop O Down solar project of the yearDespite all of these forward-thinking initiatives, Bishop O’Dowd had a problem: With a two-story building facing southeast, the classrooms get too hot during the day, causing students to lose focus. The sun also shines a glare that makes seeing the fancy new audio/visual equipment a struggle.

At that point, some schools may just put in air conditioning, but AC would require a new electrical plant as the current one is 60 years old. Also, an investment there would take away from the school’s long-term goal of adding PV (Malmgren’s estimates show that this project would cost 10 percent of what an AC overhaul project would have cost).

“We have been trying to install PV for years and could not make the numbers work because of roofing replacement costs, etc.,” Malmgren says.

The eventual solution is almost too obvious: Kill two birds at once and add awnings made of solar panels. John Orfali, a solar installer who worked with the school on a system for its Center for Environmental Sciences, said they started thinking about this project two years ago.

Ultimately, Malmgren wanted to accomplish these four objectives:

1. Lower the interior temperature of the classrooms by shading and cooling the heat gain in the concrete walls to avoid AC in all classrooms.

2. Lower the light infiltration around the interior shades to allow better projection of the electronic curriculum during the low morning sun angle cycle.

3. Optimize the use of the structural support for a dual purpose to accomplish both the shade and PV electrical production, eliminating the roofing/shade component.

4. Use the exposed components of the shade and PV as a visual educational tool as part of the school’s sustainability program and commitment to the health of the environment.

“We started looking around for a product that could accomplish these goals and couldn’t find one,” Orfali says. “We eventually found a single panel awning, but we needed a larger awning to cover the classrooms and the wall. So, that didn’t work for us.”

The 198-panel system is generating close to 250 kWh, which could save the school about $15,000 per year.

The 198-panel system is generating close to 250 kWh, which could save the school about $15,000 per year.

The Prototype

As they kept searching for the perfect solution, they found one at an architecture firm that had designed their own and installed it on their building.

Racking used: IronRidge XR10 Rails with a unique curved shape 

Using that as their model, Orfali and Malmgren had to go design something unique. Fratessa Forbes Wong Structural Engineers of Oakland, Calif., were the structural engineers for the awning structure design, and they contracted a manufacturing firm to create the awning structure.

The thing about Malmgren is he’s not your typical school facilities director. He previously worked for NASA, and he was behind the plans for the awning’s target temperature reduction, the expected return of energy from the PV system and the return on investment of those two attributes working in concert versus the costs/benefits of installing a new AC system.

“Trying to solve two problems, I commissioned Integral Group to design an engineering study to determine the effect of shading the building walls to lower the stored latent heat in the classroom walls,” he says. “We also did a shade angle study with Sketchup to make sure the shade would block the light infiltration around the interior shades to allow better projection of our electronic curriculum during the low morning sun angle cycle.

“We determined, in theory, that we would lower the classroom interiors by 5 to 10 degrees F by adding shading,” he continues.

The project officially came to life in April, first as a 28-panel prototype attached to the hottest two classrooms in order to test the system architecture and the calculations for reduced heat and glare.

The prototype was a success, which green-lighted the full project over the summer.

As for the electrical side of the equation, Orfali went with Enphase microinverters because “we try to only install microinverters, and this was very much in line with our standard solar installation direction,” Orfali says. “We feel it’s state of the art for small to medium projects.”

Bishop O Dowd solar awnings 1

The Numbers

“It’s interesting because the project reduced energy consumption while producing it. The multifunctional aspect of it is very exciting,” Orfali says.

Bishop O Dowd solar awnings 4That’s really what, we assume, won the hearts and minds of voters for this year’s Rooftop award. Solar power generation is a great way to produce renewable energy, but being able to also reduce the total amount of energy that a given building needs to produce to cover usage in the first place, is perhaps an even nobler accomplishment. This is especially true in California due to Title 24 energy efficiency standards, which are focused on reducing the state’s overall energy consumption. The success of these standards and other energy efficiency efforts is a significant factor in California’s per capita electricity use remaining flat over the last 40 years while the rest of the country’s use continues to rise. In 2008, California set bold energy-use reduction goals, targeting zero net energy (ZNE) use in all new homes by 2020 and commercial buildings by 2030. The ZNE goal means new buildings must use a combination of improved efficiency and distributed renewable energy generation to meet 100 percent of their annual energy need.

Inverters used: Enphase Energy’s M215 Microinverters 

So, that’s the environment in which Bishop O’Dowd operates, where any additions or upgrades need to take all of this into account.

Now that the system has been up and running, we can see the impact in real time thanks to the microinverter communication system Orfali installed. When Orfali checked for us over the phone on a random day in October, the 198-panel system was generating in full close to 250 kWh. At 15 cents per kWh per day, producing 250 kWh a day, Malmgren expects a savings of about $15,000 per year, which would pay for the system in about six years (which doesn’t include the savings achieved by not having to install and run AC).

But maybe more importantly:

“The classroom temperature is much lower, and the visuals are working better without the glare from the sun,” Orfali says. “The teachers have given the system high praise.”

Thanks to some innovative designs and forward-thinking, this Project of the Year will help Bishop O’Dowd try to achieve its zero-net-energy goal by 2025 and also provide a better learning environment for its students.

— Solar Builder magazine

VOTE: 2015 Solar Builder Project of the Year Awards — Roof-mounted

Bishop O’Dowd High School

BOD South Side ArrayOakland, Calif.
Completed: Aug. 1, 2015
Size: 50.960 kW

Bishop O’Dowd High School has a two-story classroom building facing southeast. The classrooms get very hot during the day when classes are in session. They want to reduce the heat to improve the learning experience of the students. They either had to install air conditioning or create an awning to shade the windows. They opted to create an awning structure that uses solar panels to create shade and electricity. The new solar (PV) powered awning shade structure improves the indoor environmental quality (IEQ) for students and faculty by reducing temperatures by 7 to 10 degrees on the south side of the building. It is also more financially sustainable at just 10 percent of the cost of an expensive energy intensive air-conditioning system. Additionally, at a count of nearly 200 solar panels, the project aims to generate $15,000 worth of electricity energy savings each year. Finally, O’Dowd can be proud to take another step forward in its environmentally sustainable goal to be zero-net energy and reduce overall GHG emissions. The teachers have given the system high praise.

Developer: John Orfali
Contractor: Save a Lot Solar
Module: Trina Solar
Inverter: Enphase
Mounting: Iron Ridge

Camillus House

Camillus House Energy ProjectMiami, Fla.
Completed: June 16, 2015
Size: 20.7 KW

The Camillus House Energy Project is the result of an experimental course to incorporate a hands-on approach to philanthropy for students at Florida International University. Communication Arts student Chloe Danielle Castro won the grant for IDEAS For Us, an international sustainability NGO based in Orlando, whose mission is to develop and implement solutions that create a better and more sustainable future for all. As the course progressed, the idea was for the project to benefit others as well as the environment. So together, she and the team at IDEAS For Us created an energy project concept by identifying a set of practical goals that would have the largest community impact. Along with other initiatives (LED lights, smart thermostats) they added a 20-kW solar array on one of the Camillus House residencies. The benefits of this bi-fold plan will help to lower utility bills for Camillus House, and power a portion of their building from clean renewable energy, ultimately allowing them to allocate more funding to their mission of helping people in need. The local contractors included Citizen Energy, and Advanced Green Technologies, both who made hefty contributions to the project. The project also received a solar grant from FPL, which allowed for the team to double the solar array from 10 kW to 20 kW.

Developer: IDEAS For Us
Contractor: Advanced Green Technologies (AGT Solar) / Citizen Energy
Module: HANWHA Solar One, 305W Polycrystalline Photovoltaic Modules
Inverter: Sungrow SGKU-60KW inverters
Mounting: Panel Claw – Polar Bear III Flatroof Mounting System

Be Like Brit

Grand Goave, Haiti
Completed: Nov. 28, 2014
Size: 30 kW

In January 2010, Britney Gengel, a 19-year-old student from Massachusetts was killed in the devastating earthquake that struck Haiti while volunteering in one of the country’s local orphanages. To honor Brit, her family started a foundation and built a 22,000-sq-ft earthquake-proof orphanage shaped in the letter B, for Brit, in Grand Goave, Haiti. Prior to the installation, Be Like Brit got its electricity from the local utility, which was unreliable and cost the organization around $4,000 per month. Solect, along with two local subcontractor partners from Massachusetts, sponsored two installation team members to travel to Haiti to lead the installation. Solect donated 50 solar panels to the orphanage in order to manage construction costs for the organization and ensure that more of the non-profit’s donations could be used to provide care for the children, instead of paying for electricity. The finished project now provides 60% of the electrical needs of the orphanage. The project is one of a kind in that it utilizes large-scale battery storage for a commercial project. The battery system for Be Like Brit consists of 48 two-volt batteries, which is an incredibly large amount of back-up power for a system of this size.

Developer: Solect Energy
Contractor: Solect Energy/ Downing Electric
Module: Canadian Solar
Inverter: Magnum
Mounting: Iron Ridge

Schaedler Yesco Distribution

solar Pennsylvania distributorHarrisburg, Pa.
Completed: May 18, 2015
Size: 1.53 KW

Schaedler-Yesco Distribution had some inventory they acquired a few years ago while solar was booming in Pennsylvania that had been sitting on the shelves in recent years. Upper management wanted to discard or dispose of the excess inventory but their energy manager was reluctant to get rid of it. Contractor Edwin L. Heim Co. had discussions with them and offered its labor for both systems if they could supply materials for both. The Schaedler Yesco first system now ties into a 225 amp panel, at 120/208 volt three-phase four wire. In the future, the Engage cable can be extended to serve 18 additional microinverters to complete circuit one. The second system is similar except the tie-in was to a 200 amp single phase panel. This complete system would be 35 microinverters and modules (8.925 KW total). The six microinverters now will become seven in the future on circuit one. Two more circuits can be added in the future for 14 microinverters and modules on each circuit. The infrastructure was designed and sized for the complete system at the beginning.

Developer: None
Contractor: Edwin L. Heim Co.
Module: REC Solar
Inverter: Enphase
Mounting: Ballasted Roof Racking/ AET

University of Miami Frost School of Music

University of Miami solar awardCoral Gables, Fla.
Completed: Jan. 7, 2015
Size: 71.5 kW

Designed by award-winning architects Yann Weymouth and HOK, and constructed by Skanska USA, the University of Miami’s new Frost School of Music facility boasts two buildings with 41,089 sq ft of upscale teaching spaces and beautiful curb appeal. Located on UM’s Coral Gables campus, the Patricia Louise Frost Music Studios is seeking to be the first LEED Platinum certified building in the City of Coral Gables, Fla. Additionally, the completed rooftop solar arrays are built to withstand 180 mph wind speeds, qualified for a 20-year NDL on all penetration flashings from the roofing manufacturer and helped the building qualify for two LEED points in the energy efficiency category. The roof system from Siplast was unique because of the LEED point acquired through the Eco Active cap sheet and the ability to bundle the light-weight concrete decking and mod bit roofing system under the same 20-year warranty. The completed solar arrays will offset 13% of the building’s total energy consumption and produce 101.344 MWh annually.

Developer: HOK (Hellmuth, Obata & Kassabaun, Inc.
Contractor: Skanska USA Building Inc.
Module: Canadian Solar
Inverter: SMA
Mounting: Sunlink

WaterShed Sustainability

Rockville, MD
Completed: April 7, 2015
Size: 11 kW

In the summer of 2014, Standard Solar partnered with Pepco to develop an innovative behind-the-meter solar microgrid demonstration project at the WaterShed Sustainability Center in Rockville, Md. It is a rare installation for both its technology integration as well as its behind-the-meter project type. The solar microgrid project was developed in a public setting designed to highlight the system’s capabilities. Pepco’s WaterShed Sustainability Center showcases a variety of environmental initiatives and seeks to educate the public about energy-efficient and environmentally-friendly practices. Incorporating grid-integrated storage with solar PV has the potential to reduce overall PV project costs and offers new benefits to hosts, including backup power, demand reduction and peak shaving. The system can seamlessly charge and discharge from the grid, islanding itself as needed to complement the electricity grid and improve load balancing. With the help of an intelligent load control system, the microgrid can increase its autonomy in a grid outage situation. The system can be configured to perform multiple functions, manually or on-demand with customer programming.

Developer: Pepco Holdings
Contractor: Standard Solar
Module: Siliken
Inverter: Princeton Power Systems
Mounting: DPW

Now… vote!
Check out the Ground-mounted nominees

— Solar Builder magazine