Optimizing Radiant Systems for Energy Efficiency and Comfort
New practical design and operation tools for radiant cooling and heating systems will help capitalize on the energy savings over conventional all-air systems
The Regents of the University of California, on behalf of the Berkeley Campus
Recipient
Berkeley, CA
Recipient Location
9th
Senate District
14th
Assembly District
$2,880,178
Amount Spent
Completed
Project Status
Project Result
The project is complete. The recipient developed: sizing and operation tools to provide reliable methods to calculate energy performance of radiant systems while maintaining comfort, energy, cost, and comfort data to provide real world examples of energy efficient, affordable, and comfortable buildings using radiant systems, and recommendations for Title-24 and ASHRAE Standards advancements. The research team used full-scale laboratory experiments, whole-building energy simulations and tool development, and field studies and control demonstrations to develop guidance and tools to help the building industry adopt radiant systems. Recommendations for revisions to relevant codes and standards will continue to be communicated to the responsible organizations by the research team, who regularly participate in committees and conferences related to Title-24 and ASHRAE
The Issue
Radiant heating and cooling systems deliver or absorb heat through a building's surface. Application of radiant systems has increased in recent years as they provide an opportunity to (1) achieve energy and peak demand savings compared to conventional all-air systems, (2) eliminate duct losses, and (3) circulate less allergens. Despite this growth, operation of radiant systems can be challenging due to a lack of familiarity within HVAC design and operation professions because there is limited guidance and inappropriate tools to assist designers and building operators. New and/or revised definitions and methods for the design, sizing, and control of effective radiant systems are needed.
Project Innovation
This project develops new design and operation tools for radiant cooling and heating systems in order to provide standardized guidance for radiant systems in commercial buildings. The agreement includes full-scale laboratory experiments, whole-building simulations, development of simplified models for radiant system controls, validation of these new methods in field studies, occupant satisfaction surveys, and an update to Title-24 for radiant systems. The project produced: 1) a simplified tool for calculating the cooling load and cooling capacity of a radiant slab system, including calculation methods with significant direct solar radiation, 2) a simplified online operational tool for radiant slab systems, and 3) updates to the Title 24 Alternative Calculation Method Reference Manual to enable improved modeling capabilities of radiant systems.
Project Benefits
Radiant systems can be an integral part of ZNE and other advanced high performance buildings and reduce energy and peak energy use and cost compared to conventional HVAC systems.

Affordability
The technology could reduce energy consumption and costs in California commercial buildings by as much as 1.352 GWh/yr and $192M/yr.

Environmental Sustainability
The technology could reduce CO2e emissions due to reductions in energy use for cooling California commercial buildings. Based on the estimated annual electric savings, implementation of radiant systems could reduce CO2e emissions by up to 360,000 metric tons.
Key Project Members

Fred Bauman
Subrecipients

New Buildings Institute, Inc.

Taylor Engineering

TRC Engineers, Inc.

Match Partners

The Regents of the University of California, on behalf of the Berkeley Campus

Price Industries
