The Net Zero Energy Challenge

By Wayne Gaw, PE, Principal and Director of Mechanical Engineering

The challenge is upon us and we are ready and able! 

The California Energy Code, Title 24, will soon require all new residential buildings to be net zero  energy (NZE) by 2020 with new commercial buildings following suit in 2030.  As mechanical engineers specializing in the design of HVAC systems for buildings, we have a responsibility to lead and innovate as we move towards NZE buildings. 

Our Mechanical and Building Performance teams have decades of expertise working with both Title 24 and ASHRAE 90.1 Energy Efficiency Standards to reduce energy consumption in buildings. We bring a balanced approach to sustainability and high-performance design, leveraging backgrounds in both engineering and architecture. 

Our approach to energy performance begins with reducing the need for energy.  Working closely with the architect, we assist in the orientation and massing of the building for optimal performance and develop a high-performance building envelope.  Coordinated with the envelope design, we simultaneously analyze and design an energy efficient HVAC system, optimizing for air quality and thermal comfort while also reducing first costs and operating costs.

We use performance based design analysis and modeling to understand how the building is performing, what is driving that performance and what are the best design solutions to influence it.  Dynamic thermal building simulation models are used to predict energy usage for many different energy efficiency measures which are then assessed on a life cycle or total cost of ownership basis.

When the building and the energy systems  have been fully optimized for performance, comfort and operations at the lowest life cycle cost, we  start to consider integrating renewable energy generation such as solar photovoltaic and solar thermal arrays into the design.  As we integrate more renewable energy systems into buildings we consider strategies that maximize self-utilization of renewables and provide resiliency such as battery storage, thermal storage, demand response and electric vehicle integration. 

Finally, we develop sophisticated controls and sequences to fine tune the operation of the building and our commissioning team run the systems through performance tests to ensure everything operates as intended.

We look forward to helping you have your project meet the NZE challenge!