While taking a brief ski vacation to Jackson Hole, WY I couldn't help but notice the marketing that they put up about how green their resort is. It got me wondering – how hard would it be to build a hill for enthusiasts that is sustainable? When I say 'for enthusiasts' I mean a place that doesn't bother with man-made snow and focuses only on what's important: 4 fast, high lifts on a solid mountain with killer runs and a warming hut at the bottom that serves nothing but chili, hot chocolate, and whiskey. After all, if we're going sustainable we'll need to cut out the energy-hungry pleasantries like heated swimming pools exposed to the open air.
Since there is no ski-palace or snow machines to worry about powering, the biggest energy hog will be the 4 lifts. Why 4? Because at this sustainable ski sanctuary there will need to be between 2 and 4 peaks involved, ensuring lots of terrain for me to practice my slightly controlled form of falling. For this article, I used the most serious lift I could find data on – the Mechi Chal at Chepelare in Bulgaria. This lift will cost about 740kW to run, and give you 718m in altitude over a distance of 2.8km along with mid-way loading.
At 740kW each, the total power consumption of the lifts would be nearly 3MW. Ouch. Given the outputs of current alternative sources, that's a tall order. How tall? For starters, all of the alternative power systems are intermittent and cannot be relied upon to prevent stranding lift riders to freeze on the chairs. Infrastructure (either diesel or grid power) would need to be always available, resulting in infrastructure redundancy. There goes any chance at cost savings. But if capital expense is not a factor, what would it take to power these chairs?
Wind:
There are some days that you get off the lift and the wind is harsh enough to make it feel like you're wearing nothing at all.
“... nothing at all ....nothing at all ...nothing at all” -Stupid Sexy Flanders
What better place to stick a giant wind turbine than in a ton of wind? Given the proposed 3-peak setup, it would be possible to put up a 1MW turbine on each of the peaks. While there are the Critics of mountaintop wind, there are examples of wind generation at resorts including Jiminy Peak and Grouse Mountain. Even with their success, one must wonder how well wind turbines can withstand the nasty storms that tear through those high mountains. With the snow, ice, hail, wind, etc... there will undoubtedly be down time due to maintenance or just plain freezing.
Solar:
You might have heard people say “There are no friends on powder days,” – well, there isn't any sun either. There is one existing example of a surface list that is powered by solar energy, but it's a tow-line that is really only suitable for a bunny hill. Since the article only specifies total energy output in kWh over an unknown time frame, one can only assume a nominal power output in-line with the surface area and low levels of sun available in the mountains. We'll just knock that one off right now.
Hydro:
A small hydro system sounds pretty good – getting 3MW of water flow in the mountains doesn't seem unreasonable, even if using a run of the river system. Whistler is an example of a hydro-powered ski resort with its 33GW hydro plant capable of offsetting all of their energy needs. Granted, hydroelectricity will severely limit the locations where this ski hill could be located, and require that the dam be operated by workers, but what kind of water source would be needed? According to this powerpoint from the Canadian government, the equation for a small power system can be approximated as:
Power (kW) = 7 * Head (m) * flow(m^3/sec)
Therefore, a 3MW system requires the product of water flow and head height to be 428 m^4/sec. Not impossible, but I would assume the places that have a mountain with great snow and terrain near a river that runs year-round with these specs to be very remote indeed.
It seems that there are too many significant challenges to making the skier fully sustainable – both economic and technological. However the green initiatives continue with resorts generating what they can such as Aspen's multi-faceted generation/conservation approach. In the meantime, power consumption is no reason to stay home! That monster 740kW lift can move 2000 people per hour, therefore it costs only 370Wh per ride. On an excellent ski day of 20 runs, that's a total energy cost of 7.4kWh, or about the same as 14 hours spent in front of a 500W TV. So find a hill that still has snow and tear it up before season's end!
Of course, these are all broad generalizations and non-specific calculations for the sake of a thought experiment. I'd love to hear calculations based on better numbers or other technical challenges I haven't thought of in the comments!