The process of making snow is pretty simple, mix compressed air and water in cold weather and you will make snow. While this seems simple, there are a lot of other factors that come in to play which can make snowmaking very complicated. Home snowguns make snow following the same processes that ski resort snowguns use, but there are some differences.
Commercial Snowmakers vs Home Snowmakers
Ski resort caliber snowmaking equipment is designed to make a lot of snow per hour. Typically these snowguns flow anywhere from 15-65gpm of water each. Some snowguns have the capability to flow in excess of 200gpm based on the weather conditions. That’s a lot of water being converted into snow!
Since ski resort size snowguns make so much snow, ski resorts use industrial size air compressors and water pumps to feed the snowmakers. These compressors and pumps cannot be used at home because they draw too much power that your home cannot provide.
Since home snowmakers flow much less water than ski resort snowmakers, they are scaled down to a much smaller size. Since you are flowing less water into the snowmaker, you also need much less compressed air to nucleate the water. This means instead of using an industrial size air compressor, you can use a normal household size air compressor. So in basic terms home snowmakers are just a smaller, scaled down version of the snowmakers you see at ski resorts.
The Weather and Snowmaking
Snowmaking is very weather dependent. A common misconception is that you can make snow anytime the outside temperature drops below freezing (32ºF or 0ºC). Believe it or not sometimes you cannot make snow when it is below freezing, but you can when the temperature is at or above freezing.
This is because snowmaking goes by the wet bulb temperature. This is the ambient temperature with the humidity level factored in. It should be noted that it is rare to make snow above 30ºF unless the humidity is very low.
Ideally for home snowmaking you can start making snow when the wetbulb temperature is 27ºF or less. A 27ºF wetbulb temperature is typically achieved once the outside air temperature reaches 28ºF or less. If the humidity is low, you can reach a wetbulb temperature of 27ºF when the air temperature is 30ºF or 31ºF. You can find wet bulb temperature calculators online by searching for “wet bulb calculator”.
The higher your wet bulb temperature, the wetter your snow quality will be. As the wet bulb temperature drops, your snow quality will increase by getting drier.
Home snowmakers that run off of a standard garden hose work better in marginal snowmaking conditions. This is because the snowmaking process these snowmakers follow require them to use more compressed air (CFM). So even though they make much less snow compared to our snowmakers that run off of pressure washers, they will make higher quality snow in marginal snowmaking conditions or make snow when our other snowmakers can’t.
Making Snow in Warm Areas
People always ask us if they can make snow in the deep south where they maybe get a few nights per year where it gets below freezing. The answer is yes!
Anywhere it gets below 28ºF you can make your own real snow with our home snowmakers. Over the years we have had people make snow as far south as central Florida.
The issue with making snow in the south is that you deal with warmer tap water temperatures. Sometimes this means you have to wait until it gets a bit colder than 28ºF to make snow. Most people don't have any issues making snow at all even with the warm tap water.
Water Temperature and Snowmaking
Ski resorts let the water they use for snowmaking sit in large retention ponds that they aerate to prevent the water from freezing until it is used. They let the water sit in these retention ponds so that they can get the water as cold as possible without it freezing. The cooler the water temperature, the better it is for snowmaking. Ski resorts also use special chillers to cool the water to around 34ºF.
Since most household tap water is 50ºF ore higher you need to compensate for the warmer water when trying to make snow. All of our home snowguns are designed to operate with normal household water temperatures.
For those that live in warm areas, you may want to use longer lengths of water hose when you are making snow to try and lower your water temperature or try cooling your water down by other means.
Internal Mix and External Mix Snowmakers
There are two types of snowmakers, internal mix and external mix. Internal mix snowmakers mix the compressed air and water INSIDE of the snowmaker. External mix snowmakers mix the compressed air and water on the OUTSIDE of the snowmaker. Each design has it benefits and drawbacks.
Internal mix snowmakers tend to be more efficient because they use less compressed air and tend to work better in marginal snowmaking conditions. Since the air and the water mix inside of the snowmaker, internal mix snowmakers rarely have problems in windy conditions. It is for these reasons that all of our snowmakers are internal mix. This is also why most snowmakers at ski resorts are internal mix as well.
External mix snowmakers require more air (CFM) in order to operate. As a result they are not as compatible with smaller sized air compressors. The nucleation nozzle set up on external mix snowmakers doesn’t work too well in windy conditions.
Often times the mist from the nucleation nozzles blows BEHIND the snowmaker if the wind is blowing against your snowmaker. This prevents you from making snow in windy conditions.
External mix snowmakers are also highly prone to freezing on windy or in very cold conditions at the nucleation nozzles. If the nucleation nozzles freeze, your snowmaker will not be able to make snow.
Home Snowmaking without Compressed Air
We get a lot of questions from people each winter about making snow without an air compressor. While ski resorts are able to make snow without compressed air, it cannot be done on the home scale. We wouldn't really call it "snow" that the airless snowmakers at ski resorts make either.
Ski resorts use an additive in their water for airless snowmakers and due to environmental laws this additive is not available for sale to the general public, plus it is very expensive.
Airless snowmakers at ski resorts also use special nozzles that are very expensive. As mentioned before, ski areas pre- cool their water to get it as cold as possible. This combined with the additive helps the water freeze extremely quickly.
The major drawback to airless snowmakers is that they can only operate in really cold temperatures. Airless snowmakers at ski resorts are known to make VERY POOR quality snow and they produce more "ice balls" than snow.
No matter how fine of a mist you get from a certain nozzle or how powerful your pressure washer is, you just cannot make snow without compressed air. You need the compressed air to super cool the water in order to create the “seed” used to form snow. Using just a pressure washer to try and make snow without compressed air will result in making ice at the very best.