All-weather snow machine driven by solar energy

Technical snowmaking is the only solution to run ski slopes at the beginning and at the end of the winter season if natural snow is missing. However, technical snowmaking has several shortcomings e. g. high water and power consumption. Furthermore, with current snowmaking technology, snow can only be produced below wet-bulb temperatures of approx. -2.5 °C for compressed air and water guns or below approx. -4 °C for fan guns. This paper presents the concept of a snow machine which can be driven by renewable energy sources, able to produce high quality snow at temperatures above 0 °C, in all-weather conditions, and even in high summer season. The proprietary technology is based on a steam jet ejector chiller (SJEC) and uses the triple point of water. The thermal energy for the ejector can be provided by solar collectors or by a biomass steam boiler. Water is the only working fluid in the entire refrigeration system, which guarantees an ecologically friendly concept for the snow supply. Within the paper, the first operational experiences of the prototype as well as performance figures are presented. Furthermore, a concept for the solar circuit of a solar-assisted snow machine is presented. Subsequently, the system design and system performance of a solar-assisted machine will be evaluated for different scenarios. The evaluation is based on simulation results gathered with a model based on mass and energy balances.