ET24SWG0002 - Root Zone Heating

This is a field study which is the second phase of a market and technology study for natural gas efficiency technologies for controlled environment agriculture (CEA). The CEA and Greenhouse HVAC Market and Technology Study (ET23SWG0003) and completed in 2024 characterized California's CEA market [1]. A major finding of the study was the energy savings potential from root zone heating (RZH) technologies for greenhouses.

The objectives of this proposal are to collect data in the field to quantify savings by the size of heat distribution system as well as the delivery system and start scoping for measure package development to support creation of a Greenhouse RZH measure in California. The technology readiness level is TRL 9 (mature), with multiple systems operating in the state of California.

A field trial will consist of (3) greenhouse growers installing RZH technology in at least (1) greenhouse range (or zone of control) each. This field evaluation would collect data from RZH systems in existing greenhouses to model energy savings by California climate zone to enable a deemed measure package to be developed in a third phase of the study. Data loggers will be deployed to collect data of greenhouse space temperatures and heating system operation. The completion of this field evaluation will be an initial measure package plan scope for a greenhouse RZH measure.