Refrigeration energy consulting company Tewis Smart System is behind the conversion of the medium temperature R404A refrigeration system to R450A in a 900m2 Dia supermarket in Valencia. R450A, sold by Honeywell as Solstice N13 and originally developed as an alternative to R134a, has a GWP of around 600 and is composed of 42% R134a and 58% R1234ze(E).
While the new gas is expected to bring energy savings through increased system efficiency, in a country where F-gas refrigerants are taxed, the conversion to a lower GWP alternative will bring immediate cost benefits of €21.4 /kg now, rising to €42.7 /kg in 2015.
The medium temperature package conversion took place on a Zanotti rack in June. The conversion, aided by Tewis, was reported to be trouble-free with the main change being to the expansion valve.
The installation is said to be operating as expected and meeting specifications and requirements. Tewis is monitoring the system to obtain real and accurate values of the new consumption. Energy readings will extend for a few months to ensure that the conclusions are realistic, representative and sustainable over time, taking into account the variation of temperatures throughout the warmer seasons.
“The first results are very promising,” commented Gabriel Sánchez, DIA’s energy department head, “but we want to carry out measures and reliable monitoring for longer time to see the evolution with higher temperatures, and thus get conclusions.”
“After an analysis of conditions and store equipment, we concluded that the 404A replacement by Solstice N13 was the best option to minimise energy consumption,” said Javier Atencia, Tewis Cchief technical officer. “Through a detailed preliminary study we made sure that this change of a higher pressure gas to a lower pressure one was possible in this shop from a technical point of view.”