Petal: Energy
Imperative 06: Net Positive Energy
 
Photovoltaic (PV) Canopy

To achieve Living Building Challenge certification, The Kendeda Building must function at net positive energy – meaning it must harness more energy (in this case via PV solar panels) than it consumes. One hundred and five percent of the building’s energy needs must be supplied by on-site renewable energy on a net annual basis, without the use of on-site combustion.

As with other natural resources, The Kendeda Building must balance the energy it uses with the energy it is able to produce. During the design process, consideration was first given to passive design such as using daylight to reduce energy demands and then to energy conservation measures such as efficient mechanical systems. Passive design and energy efficiency reduce the size of the PV array that makes the building net positive energy.

The 330 kW (DC) solar array is expected to generate over 455,000 kWh of electricity per year that will directly serve the building’s energy demands including lighting, heating and cooling, water systems, and plug loads. In addition to those loads, the PV system is designed to satisfy the five percent net positive factor that is required for Living Building Challenge certification as well as a safety factor that provides a buffer against unknowns. A lithium ion battery serves as the emergency back-up system for the building in the case of power outages. 

The Kendeda Building's radiant flooring system borrows water from the campus central chilled water loop. Water from the campus connection is metered, the building's proportional share of energy consumption is calculated, and an energy offset is supplied by the building's PV array to the grid in order to meet the annual net positive energy requirement.

When the PV array is not producing adequate amounts of electricity, the building loads run off of electricity from the grid. All electricity generated beyond what the building uses goes instantaneously to adjacent buildings for their use thereby reducing the amount of electricity needed from the utility provider. 

The PV canopy is also a key design feature that gets The Kendeda Building to net positive water. 

Images
The Kendeda Building's 330 kW (DC) solar canopy is comprised of 913 PV panels. The PV canopy is also a primary rain water collection surface. Photo Credit: Vertical River.
In addition to generating electricity, the solar canopy reduces energy consumption by providing shade for the building. Photo Credit: Miller Hull Partnership.