| HN Mirror

That's pretty cool that they are selling "external mix" plans/kits. Snowmaking (at scale) is incredibly energy intensive and over the last few years many resorts have been moving towards various "low-energy" gun designs, which basically means external mix.

They definitely don't make as good snow at marginal temperatures but it's impressive what they can do given a lot use 1/20th of the compressed air compared to a tradition air/water snowgun.

A tradition air/water gun is just an 1.5" air inlet, a 1.5" water inlet, a mixing chamber and a nozzle. At higher temperatures, they take an incredible amount of air. We had a few guns that could take 300 horsepower worth of an air compressor, each, to run at -2.5 celsius wet bulb. As is gets colder it gets a little more efficient.

There are some designs that are basically the same but incorporate a "baffle" that attempts to cut down the size of the mixing chamber when there's a high air/water mixture to make them more efficient, but those baffles would often get stuck open, making them useless.

A fangun is the style of snowgun that uses a giant electric fan to project the snow out from the gun. There is an onboard electric air compressor hooked up to a few nozzles that spray out a mixture of air and water. The tiny droplets freeze into the "nucleus" (a tiny ice particle), which other droplets from water-only nozzles bind onto and freeze, creating a "snowflake".

An external mix gun is basically a fangun, minus the big electric fan, and suspended 30+ feet in the air on a pole. A small number of nozzles spray out an air/water mix, creating the nucleus, and then water only nozzles spray out droplets that then bind to the nucleus. It works but needs to be a bit colder, and they are much more susceptible to winds (especially cross winds). If winds don't allow the two types of sprays to mix, you get a nice skating rink instead of snow!