Science Energy Ask Pablo: Is Indoor Skiing Really That Bad? By Pablo Paster Writer California Polytechnic State University-San Luis Obispo Presidio Graduate School Pablo Päster is an energy and sustainability management consultant who wrote a weekly advice column for Treehugger from 2009-2012. our editorial process Pablo Paster Updated October 11, 2018 James D. Morgan / Contributor / Getty Images Share Twitter Pinterest Email Science Renewable Energy Fossil Fuels Dear Pablo: How bad is indoor skiing is for the environment? I have heard of places in the Middle East where you can ski indoors, even during the summer. I have been holding on to this question for a while but I recently had the opportunity to visit Ski Dubai at the Mall of the Emirates on a recent business trip to the Middle East. In a land of countless "world's largest" titles it is surprising that Ski Dubai is not the biggest indoor skiing area in the world, but it does have the distinction of featuring the first indoor black diamond (> 40%/21.8° slope) ski run. My initial decision to go to Ski Dubai were greeted with declarations of hypocrisy by my sustainability-minded friends but I decided to keep an open mind. An indoor, refrigerated ski slope in the middle of a desert country that reaches 50° C in the summers sounds like the definition wasted energy, but is it really? Tell Me More About Ski Dubai Rubina A. Khan / Contributor / Getty Images Ski Dubai spans 22,500 m2 and has an elevation drop of 85 meters. It takes a few minutes to reach the top via the tow bar or four-person chairlift but a proficient skier can easily return to the bottom in less than a minute. 180 AED (49 USD) gets you a two-hour slope pass with equipment and clothing rental. The snow surface is maintained at -16° C and the air temperature is -1° during the day, decreased to -6° when 30 tonnes of fresh snow are made each night. Old snow is moved to a melt pit, where the energy absorbed by the melting snow is used to pre-cool incoming air for the Mall of the Emirates' air conditioning system. The skiing area is surrounded by two layers of advanced insulation panels around a 4 meter air gap. While the exact insulation value was nowhere to be found, Ski Dubai is much better insulated than any refrigerated warehouse that I have ever done an energy audit on. How Much Energy Does Ski Dubai Use? robert wallis / Contributor / Getty Images Ski Dubai did not respond to my request for information but it is possible to estimate their energy use with information available on their website. Given the temperature maintained in Ski Dubai and the average outdoor temperature, which can reach 50° C, the refrigeration system must overcome 11,600 cooling degree days. This means that the average temperature difference between the inside of the building and the outside is almost 32° C. Depending on the exact insulation used at Ski Dubai my best guess is that it uses between 525 and 915 Megawatt-hours (MWh) annually just to maintain its temperature, possibly even more. Add to this the heat energy that needs to be removed from water to create snow, at least 700 kWh per day, or 255 MWh per year. So, How Bad Is Indoor Skiing? Construction Photography/Avalon / Contributor / Getty Images Ski Dubai's electricity is generated primarily from natural gas so its annual 1000+ MWh of electricity use results in at least 500 tonnes of greenhouse gas emissions. While this may sound like a lot, keep in mind that Ski Dubai has thousands of visitors each year, many of which might otherwise hop on a jet to go skiing in the Alps. The annual greenhouse gas emissions of Ski Dubai are equivalent to about 900 round-trip flights from Dubai to Munich (561 kg per person, per round trip). It's easy to target Ski Dubai as a model of waste and excess but there are far too many other, more wasteful practices in Dubai that are much more worthy of our negative attention including outdoor air conditioning, (cancelled) plans for a refrigerated beach, and a single building with 57 pools.