As if we didn’t already know that mega-mansions devour energy, here’s even more proof: A 10,000-square-foot house doesn’t just use 10 times as much energy as a 1,000-square-foot residence—it sucks up 30 times as many resources. That’s according to a report delivered last year to Pitkin County by consulting firm Resource Engineering Group. Nor does that increased consumption occur incrementally. For reasons unclear, houses develop sharply larger appetites for energy starting at about 7,200 square feet.

The report drew on electricity and gas records for nearly 900 homes in Pitkin County from 2014 through 2017. The study’s author, August Hasz, hypothesized that, not surprisingly, larger homes are more likely to have humidification and snowmelt systems, pools, air conditioners, and expanses of glass, all resulting in higher energy use.

With these numbers as the foundation, Pitkin County has begun a conversation with architects, real estate agents, and construction firms about revamping its Renewable Energy Mitigation Program (REMP), as accumulating greenhouse gasses threaten to upset the climatic applecart. Moreover, the government-mandated Fourth National Climate Assessment, released last November, warns not only of increased risk from wildfires in Colorado and other Southwestern states but also of intensifying droughts. Future ski seasons will likely be shorter. Expect more rain, less powder.

REMP, the first of its kind in the world, was adopted in 2000 by both Pitkin County and the City of Aspen. It targets the heavy energy consumption of exterior amenities like snowmelt systems, pools, and spas.

Homeowners can mitigate the impact with on-site renewable energy, such as solar photovoltaic or geothermal heat pumps. Or they can pay a fee—it’s not a tax, some involved insist—that is funneled to the nonprofit Community Office for Resource Efficiency. CORE then provides rebates and grants for projects that help reduce greenhouse-gas emissions. The goal? To eliminate twice as much pollution as a homeowner’s proposed outdoor swimming pool or other energy guzzler would produce over 20 years.

At a Carbondale energy conference last year, Ed Mazria, founder of Santa Fe-based Architecture 2030, said that to solve the climate crisis we must substantially trim the enormous appetite of buildings. Locally, a 2014 study found that 70 percent of emissions in Pitkin County were associated with the built environment.

But only Pitkin County is proposing changes. Aspen’s and the county’s REMP programs diverged early on. Aspen’s chief building official, Stephen Kanipe, who helped create REMP in the late 1990s, says the city has focused on exterior energy use, while the county requires mitigation for the overall increased energy use of any new or remodeled building larger than 5,750 square feet. “There is no relationship between the city program and house size—not one itsy, bitsy piece,” emphasizes Kanipe, who is retiring in March.

Last year, county officials started to discuss sharply increasing fees and mitigation requirements, as well as shrinking the maximum size of new homes from 15,000 square feet to 10,750.
Pitkin County Commissioner Greg Poschman and colleagues have indicated support for these more muscular regulations but want community dialogue first. Poschman likens the challenge of climate change to that of World War II (his father fought in the 10th Mountain Division). Today, as during the war, “despair and complacency are equally unwarranted,” he says.

Many in the development community are skeptical. “Soak the Rich or Save the Planet?” asked the headline of a December op-ed in the Aspen Times about the proposed changes. (A follow-up piece the next month clarified some incorrect assumptions.)

Even architects sympathetic to the county’s goals disagree with the approach. “Climate change is real, and buildings do represent a large component of energy use and greenhouse emissions,” says Nick Ketpura of Bldg Seed Architects. But though he’d like to see more ultra-efficient homes everywhere, he and Bldg Seed principal Ramsey Fulton prefer incentives over penalties.

Ex-Aspen Mayor Bill Stirling, a real estate agent who supports more exacting requirements, likens the current conversation to the one 20 years ago, when he helped create the original regulations. “My colleagues say, ‘You’re going after the rich,’” he notes. But he believes the disagreements can be resolved.

Aspen itself has no plans to revise its REMP requirements. Instead, says Chris Menges, the city’s sustainability programs administrator, the municipality intends to execute steps identified in its 2018 climate action plan, with the goal of reducing emissions 72 percent by 2050.

CORE, meanwhile, with plenty of money in its coffers, plans to ramp up spending to further improve energy efficiency. Executive Director Mona Newton also foresees the nonprofit playing a role in the eventual transition to beneficial electrification, which means that energy needs are largely met through renewables.

Kanipe points to statistics on CORE’s website as evidence of REMP’s value. Since 2011 alone, the organization estimates that it has leveraged REMP payments into nearly $3 million in annual energy savings while avoiding 22,432 metric tons in carbon dioxide emissions each year. It’s a big step in the right direction, but is it enough to offset the outsize energy diet of Aspen’s largest homes?