One hotel in Reno, Nevada is not like the others, but not for the reasons you'd expect. Sure, the Peppermill Resort Spa Casino's two 19-story towers are unique, as are the 2.1 million square foot (195,000 sqm) interior, 1,635 guest rooms, 43,000 square-foot (3,995 sqm) spa, Tuscan-themed decor and larger-than-life casinos, restaurants and nightclubs.
This difference is one you can't see: how it's heated. Water from a geothermal aquifer 4,400 feet (1.34 kilometers) underground powers the Peppermill's massive heating and hot water systems, saving a cool $2 million annually versus its former, conventional power source, natural gas.
Geothermal expert Dr. Jim Combs of Geo Hills Associates calls the Peppermill "the only resort in the United States whose heating source is totally provided from geothermal energy produced on the immediate property." Going green has earned the Peppermill commendations from far and wide, including the U.S. Congress.
Here's a simple explanation of how it works:
1 – Water at 174° Fahrenheit (79° Celsius) is pumped from beneath the property, up to 1,200 gallons (4,542 liters) per minute.
Dean Parker, Executive Director of Facilities at the Peppermill Reno, and the geothermal heat exchanger… (photo credit: Andrew Bender)
2 – In a heat exchanger in the Peppermill's boiler room, geothermal water heats copper tubes filled with water from the municipal water authority. The two types of water never touch, as one would contaminate the other.
3 – The municipal water is pumped to the hotel buildings, while the geothermal water is pumped back into the aquifer, where nature reheats it for its next use.
Since the Peppermill switched from natural gas for water and heating in 2010, its four behemoth natural gas boilers have sat idle. "They haven't been turned on in the last three years," says Dean Parker, Executive Director of Facilities. Geothermal is so reliable that he plans to sell two of the boilers.
So why doesn't everybody go geothermal? Well, it's still early days for the technology, making it a gamble, although if there was ever a place to gamble, it's Reno. The Peppermill's odds were good since it already had a smaller geothermal facility, and Nevada (along with Oregon and California), is one of the most geothermally active regions in the nation; the U.S. leads the world in geothermal energy, with some 30 percent share.
…which does the work of four of these giant boilers and saves about $2 million a year in natural gas. (photo credit: Andrew Bender)
Yet despite extensive consultation with geologists and geothermal experts, without drilling there was no way to know the volume, temperature or location of the hot water below – or even whether it existed. "If it hadn't worked," Parker says, "I'd have been packing my bags."
Parker says the crew drilled for about a month, and just as it was looking bleak, they found the aquifer. Management eventually invested $6.5 million in the new geothermal system which, at a savings of $2 million a year, will pay for itself within the next year. "When you have a four-year return on your investment, it's almost a no-brainer," Parker says.
Parker's team had also considered other alternative energy sources, but, he says, "Solar and wind power just didn't pencil out." Unlike those, geothermal is not dependent on above-ground conditions. "It's just constant," he says. "If the water is 174 degrees, it does not heat up to 175 degrees, and in the last three years it has not dropped even one degree either."
Eventually, Parker hopes to drill deeper and hit a subterranean steam vent. Enough steam at 220° Fahrenheit (104.5° Celsius) could power an electric plant for all the Peppermill's needs, enabling it to go off the power grid completely.
Source: Forbes
