Feeling guilty about the amount of carbon dioxide your upcoming flight will pump into the atmosphere?
Soon you might be able to fork over some extra cash at Denver International Airport to invest in projects intended to help negate your share of the environmental damage caused by air travel.
DIA is looking to become one of the first airports in the nation to offer passengers the ability to buy carbon offsets in its concourses. The offsets would pay for renewable energy and power-saving projects that help cut greenhouse gas emissions.
The airport is soliciting proposals from companies interested in setting up and running an offset program in all three concourses. The offsets could be offered through kiosks, booths, computer terminals or other means.
It's all part of the airport's renewed focus on the environment, which dovetails with efforts by the city and state to implement energy-saving procedures and technology.
"Airports and airlines are under more and more scrutiny regarding greenhouse gas emissions and how they can offset climate change," said Janell Barrilleaux, DIA's director of environmental programs.
"This offers a small step in the right direction to raise awareness and let people know that airports want to do the right thing."
The airport will award a three-year contact that is nonexclusive, meaning other providers could eventually set up shop in the airport as well.
DIA hopes to have the offset program up and running by August.
Under the plan, interested passengers would provide the details of their flights — such as the cities involved and the number of stops — to determine how much in offsets would erase their "carbon footprint," or amount of carbon emissions.
The offsets could be used for a variety of projects, such as installing solar panels in India or planting trees as part of reforestation efforts in Brazil.
A passenger could pay anywhere from a few bucks to more than $50 to offset his or her "share" of the carbon emissions on their flights.
Carbon-offset providers use varying methods to calculate flight emissions and the amount of money needed to offset them. The airport said it will thoroughly vet any program to ensure that it funds valuable, effective projects and that it uses an accepted method of calculating how much a passenger should pay. DIA also wants a third party to verify that the money is invested in the right kinds of projects.
The airport would get a share of the money collected: 10 percent of the first $1 million, 12 percent of the next $1 million and 14 percent of sales above $2 million, according to airport documents.
Carbon offsets are becoming increasingly popular, and several carriers — including Denver-based Frontier Airlines have implemented or plan to offer such programs. Consumers also may buy them through a variety of Web sites.
But there are plenty of critics. Some argue that carbon offsets are simply a way for consumers to feel better without taking tangible steps to reduce global warming. The environmental value of the projects also is debated, and some have actually emitted more greenhouse gases than they were supposed to negate.
Additionally, it's a largely unregulated market.
The Federal Trade Commission, which is looking into the industry, said last week that it's tough to track whether or not these programs are effective.
Supporters of carbon offsets say the key is to use a reputable operator that is overseen by a third-party company and conforms to strict guidelines for the projects it invests in.
"I think DIA is going to want to work with a company with a good track record, folks that have been involved developing best practices in the industry," said Susan Innis, manager of the Colorado carbon fund program for the Governor's Energy Office.
DIA acknowledges the criticism surrounding carbon-offset programs but said it intends to thoroughly scrutinize all proposals, including the calculations used to determine emissions and costs.
Barrilleaux said the airport doesn't have any specific projects in mind. Rather, it wants companies interested in running the program to pitch their ideas.
"Maybe we'd even have a menu of projects that (passengers) can pick from," Barrilleaux said.
The airport said it won't rule out "sequestration" projects that involve storing carbon underground, but the company or organization would have to provide "sufficient scientific and economical justification."
Some critics could take issue with the fact that DIA will get a portion of the money passengers pay for carbon offsets.
The airport, however, said it can't provide such services for free. It'll also use some of the revenue to cover expenses incurred in choosing an operator and tracking the success of the program.
"There is going to be a cost to the airport associated with this," said DIA spokesman Jeff Green, adding that officials don't yet know how much that will be. "We have to cover those expenses."
How much does it cost to purchase carbon offsets for air travel?
It depends on the distance of your flight and whether you have any layovers in other cities. It also depends on the "calculator" the company or organization uses to determine how much it will cost.
Following are some estimates using aspenzgreen.com, which was developed by the city of Aspen and has been approved by DIA for use in its program, for round-trip travel between Denver and . . .
* Las Vegas: $5.64
* New Orleans: $8.28
* San Francisco: $7.53