Planning to travel this summer? Whether driving down the coast or flying to Italy, many eco-conscious travelers buy “carbon offsets” that (in theory) cancel out the greenhouse gas (GHG) emissions their trips generate. Here’s how it works: Let’s say you fly round-trip from Los Angeles to New York. You visit the website of a carbon offset company which calculates your GHGs for this little jaunt (two tons). The company then offers you the opportunity to buy carbon credits to offset your flight.  If that sounds like a sin tax on fossil fuel consumption, it is just that.

Different offset companies do different things with the money you pay them-some are scam artists that do nothing, some plant trees, some build wind farms or turn cow poop into electricity. It’s important to choose an offset company that makes the most of the cabbage you fork over. When choosing a company, look at how much carbon per dollar they offset-in other words, if you pay $50, will they be able to offset two tons of GHGs or five or ten? And examine whether the offset measurably displaces carbon emissions. For example, I like Native Energy because it uses the money I give them to build wind farms which directly reduce the amount of coal being fed into the electric grid. Offset companies that sequester carbon are dicier, because it’s hard to measure the amount of carbon being sequestered, and it’s hard to know whether the company is actually doing something that wouldn’t have happened anyway. On the other hand, some sequestration activities like tree planting and soil restoration have other important ecological benefits in addition to carbon capture.

Here are a few carbon offset companies that have a proven track record of converting offset dollars into renewable energy projects: Native Energy Solar Electric Light Fund TerraPass Climate Friendly

I can’t end this blog without raising the issue of whether the whole concept of carbon offsets even makes sense.  Sungevity customer Annie Leonard of Story of Stuff fame has created a new short video called The Story of Cap and Trade.  It debunks the notion that we Americans can keep on partying and count on a cap and trade scheme (or scam) to keep atmospheric carbon at safe levels.  As author Dan Welch put it, carbon offsets “are an imaginary commodity created by deducting what you hope happens from what you guess would have happened”. The only sure way to keep carbon out of the atmosphere is to keep it in the ground.  That means traveling to Yosemite instead of Patagonia and powering your home with renewables instead of with coal. So if you’re now feeling skeptical about the whole carbon offset concept, here’s another idea: Go to one of the sites above to calculate your sin tax, then donate that amount to an organization that is working to stop climate change. 

Sungevity “offsets” its emissions by donating money to Vote Solar, the Alliance for Climate Protection and 350.org.  My personal favorite is 350.org because it is one of the few groups that is willing to tell it like it is:  We must get to 350 ppm of atmospheric carbon, not 700, not 450, 350, end of discussion.

-Erica Etelson