Switching from superheat to a vapor-quality control system from Danish manufacturer HB Products has allowed an ammonia (R717) cold storage facility to reduce electricity consumption by 43%.
In the facility, located in Haichiu, Romania, and built in the summer of 2020, the initial superheat control was replaced by the vapor-quality sensor system in mid-September, resulting in better control of the evaporator and the significant energy saving, HB Products said.
HB Products stated that the sensor technology is “able to make direct expansion refrigeration systems more energy efficient than traditional overfeed systems, while at the same time maintaining a low refrigerant charge.”
Australia was the first country to adopt the technology, but it is now entering European markets, with Germany, France and Romania being some of the first countries to adopt it.
In Australia, natural refrigerant pioneer Scantec Refrigeration has implemented around 20 projects over the last five years. These facilities now have an energy consumption down to 15kWh/m3/year (0.3kWh/ft3/year). “Typical values are above 30 kWh/m3 (0.6kWh/ft3/year), even for new installations,” HB Products said.
Getting contractors to accept the new technology hasn’t been easy. “Many contractors are focused on documented reliability therefore they are not eager to try new technology,” HB Products said on its website. “Few customers put pressure on the contractors to reduce the energy consumption and the focus remain[s] on proven but inefficient technology.”
HB Products’ Vapor Quality Control sensor is part of a patented control system for direct expansion refrigeration, based on actual sensor measurements, rather than theoretical calculations of superheat. The technology improves evaporator control and increases energy efficiency “significantly,” especially when refrigeration systems operate in part-load conditions, the company said.
In addition to its vapor-quality control sensors, HB Products also manufactures defrost control sensors, enabling more precise defrost cycles, with typical energy savings around 10%, the company said.
Few customers put pressure on the contractors to reduce the energy consumption and the focus remain[s] on proven but inefficient technology.HB Products