A building’s heating and cooling systems typically account for about 30 percent of the structure’s overall energy use. At Pacific Northwest National Laboratory (PNNL), researchers use specialized testing chambers to put these building systems through their paces.
PNNL’s two environmental chambers provide a simulation and testing capability to measure the performance of heating, ventilation, and air-conditioning (HVAC) systems and other building equipment. The chambers help advance new energy-efficient devices to the marketplace, update product standards, and develop building–grid integration strategies.
The two side-by-side units, also referred to as psychrometric chambers, can precisely control temperature and humidity. The chambers are the largest of their kind in the U.S. Department of Energy’s (DOE’s) laboratory system and can accommodate HVAC units of up to 20 tons (240,000 Btu/hour). One chamber simulates a house or building’s interior conditions, establishing temperatures ranging from 50 to 110 °F and adjusting humidity levels and other factors. The adjacent chamber simulates various outdoor conditions, with a temperature range of −20 to 130 °F. The chambers’ controlled internal environments allow studies to be conducted at any time of the year, regardless of whether actual outdoor conditions are extremely hot or cold.
How researchers use the chambers
During a test, a heat pump, for example, is placed in the outdoor chamber, where it is operated and monitored. At the same time, the heat pump’s outputs—air flow, cooling, and other conditions—are collected and measured in the indoor chamber. All operating conditions can be adjusted to evaluate performance under a wide range of scenarios.
The chambers test any type of equipment whose performance can be measured in a controlled environment. The units also help evaluate testing procedures, inform updates to federal appliance standards, and assess the flexibility of equipment to help manage a building’s electricity use. This ability to adjust electricity consumption supports power grid operations.
The chambers, purchased with funding from the Washington State Department of Commerce, were installed in the summer of 2019 and are components of a clean energy testbed at PNNL. The DOE’s Building Technologies Office supports most of the work conducted in the chambers.