You can step inside the new $10 million Alpine Library in San Diego County and check out a book on sustainability, or you can walk around the building itself, study its design and learn firsthand what it takes to be Net-Zero.
"Architecturally speaking, the east and west [library] facades integrate monumental, tapered, vertical concrete shade fins, densely spaced to optimally mitigate glare and solar exposure," says Architect Amanda Schultz, senior associate at San Diego-based Ferguson Pape Baldwin Architects (FPBA), who designed the project along with Manuel Oncina Architects of La Jolla, CA. She says sustainable features such as this help reduce the amount of energy to cool the space, "while preserving views out and offering excellent reading environments for users."
Thanks to eco-friendly features, the 12,900-sq-ft design-build library is targeting LEED Gold and will be the area's first Net-Zero library, as it will generate as much or more power than it consumes.
To help reach Net-Zero, the project will also utilize a solar panel system spanning its elongated roof, with panels angled south to take advantage of prevailing sun rays. The solar system is expected to produce about 108,500 kWh per year. The library's windows also take the sun in consideration, as the majority of them are located on the north-facing side, which gets less rays.
Other energy-saving features include extensive natural light and sensor-controlled LED fixtures; automatic electrical outlets that shut-off when nearby areas are not being used; and a next-generation energy system that cools and heats precise locations only when needed.
Matt Christensen with Pasadena, CA-based C.W. Driver, the project's contractor, says combining the sustainable materials into the building process was an interesting challenge.
"With zero-net energy there is a lot of focus on the envelop (of the building) and a lot of new rigid insulation to coordinate with the finishes and that was pretty difficult," says Christensen, the project manager. "With the addition of the insulation that made our wall thickness greater and the allowable distance for attaching the fiber cement board was then exceeded, so we had to come up with different attachment methods and backing, and it was a curve ball in the middle of the project."
The library's exterior is covered in elegant layers of stone veneer, plaster, and fiber cement board, "and all of it takes zero to minimal maintenance for the county," says Christensen.
Schultz says studying the building there are two relatively new technologies worth noting. First, domestic hot water is supplied by a 40-gallon, solar hot water heating system that uses no electricity to operate. Second, demand control ventilation monitors outside air to maintain CO2 levels in the building. Ventilation is provided by a dedicated outside air supply fan with a variable speed motor.
"The outside air supply fan is controlled by carbon dioxide sensors (CO2 sensors) that measure the carbon dioxide within each space and modulate the quantity of outside air to maintain a healthy environment," says Schultz. "The reduction of outside air when a space is not fully occupied has a significant impact on the total energy consumption of the building annually."
She says a building pressure relief fan with a variable speed drive, controlled by a building pressure sensor, removes air from the building to ensure proper outdoor air exchange.
The project, which opened this week, is the third design-build library in San Diego County for C.W. Driver. The other two are Fallbrook Library and Ramona Library.
Other project consultants include Manuel Oncina Architects; Hope-Amundson Engineering, as the structural engineer; McParlane & Associates, as the HVAC and plumbing engineer; ELEN Consulting, as the electrical engineer; Snipes-Dye, as the civil engineer; VanDyke Landscape Architects, as the landscape architect; ICS, as the plumbing and HVAC contractor; and Rowan Electric, as the electrical contractor.