What to Look for When Car-Shopping Besides MPG?

Hey Mr. Green,

While I very much appreciate your cash for clunkers calculator, I very much doubt I can afford a new car even with a clunker rebate. So I'm shopping for a moderately priced used car. I want high mileage, but also reasonable safety and reliability. I plan to look at back issues of Consumer Reports to try to estimate miles per gallon of various models I'm considering. Is there anything besides MPG that I should consider to keep my carbon footprint low as possible? Anything else I need to look for?  Any pertinent websites you can direct me to?

-- Dale, location undisclosed

The most helpful website for MPG of cars both new and used is the EPA’s economy.gov. Go there and click on “find and compare cars.” Your tax dollars at work. (Better check soon, before some yahoos at a town meeting howl “socialism” loud enough to get the site shut down.)

There are indeed huge considerations regarding your carbon footprint besides MPG. The biggest single one is if you really even need to own a car. More and more folks are actually getting along fine without one, with membership in a car-share service, taking cabs and mass transit, or biking.

Besides reducing their carbon footprint, they are saving a lot of money, because costs of owning and operating a car dwarf the cost of the gas it needs. Add to the gas the price of maintenance, insurance, licensing, financing, and, alas, depreciation, it takes a whopping total $9,641 to own and drive a medium-size sedan 15,000 miles per year, according to AAA. Less than a fourth of this cost is for gasoline. The rest is overhead. For comparisons of different-size cars, click here.

Finally, if you do buy a car, try to think about the bigger financial picture. Don’t simply compare cars’  MPG, but their prices too, and considering your entire energy-consumption portfolio If you have enough money to buy, say, a $15,000 car that gets 35 MPG and a $5,000 model that gets 25 MPG, you might be able to reduce your energy and carbon footprint a lot more by purchasing the cheaper model and spending the extra $10,000 on other energy-conserving measures, which could be anything from a new heating system to investing in a renewable-energy company.  

How to Recycle Propane Canisters for Camp Stoves?

Hey Mr. Green,

I have been trying to find out how best to dispose of or recycle the small propane canisters that we use for our camp stove (the green ones a bit fatter than the size of a jar of pasta sauce). Even our local hardware store didn't seem to know. Do you know?

–Donna in San Francisco

Until very recently, it was impossible to recycle those old canisters for the simple reason that nobody wanted to risk having the gas left in them blowing up or starting a fire. But now—good news for campers—you can heat up the pasta sauce at your campsite and enjoy it even more. Coleman, a major manufacturer of canisters, has introduced a "Green Key" canister. The green key that comes with the canister allows you to make sure all the remaining gas is expelled, thereby averting disaster and making it safe to recycle. To find the nearest recycler that takes them, go earth911.com, follow their instructions, typing in "steel" and your ZIP code.

Are Digital Photos Really Cleaner than Flm?

Hey Mr. Green,

During my recent Hawaii vacation, I watched tourists taking thousands of pictures and pondered the value of new digital technology in avoiding the millions of rolls of film and bad pictures that used to be processed. Do you have any idea about the savings in chemicals, film, and photo paper thanks to digital photography? Seems like a real green boon to me.

--John in Hinsdale, Illinois

Actually, the digital method isn't much easier on the environment than old-fashioned film. Sure, it takes chemicals to develop film, but think of all the toxic substances needed to make computers, printers, and ink cartridges--not to mention the hazardous waste involved in their disposal.

Since the two photography methods have such different impacts, it's a mind-boggling task just to set up a comparison because of the huge number of variables.

Digital does beat film in two realms--energy use and greenhouse-gas emissions--but isn't great in the categories of water use and waste generation. According to the most impressive study I've found, by Michael Muir at the Georgia Institute of Technology, the least energy consumption and greenhouse-gas emissions occur in digital photography when the user has an LCD monitor and ink-jet printer. This requires about half as much energy as retail film processing and releases about 40 percent fewer emissions. However, it requires much more water (digital manufacturing is a water-intensive industry) and can generate 10 times as much waste.

Also, with all digital technology, so much depends on how it's used. Even if you never print your digital images, you still wear out batteries, burn through memory cards, and spend hours gaping at them on-screen. That's when your digital efficiency can lose its edge. Fiddle around in Photoshop or upload any of those shots as screen savers, and your energy usage flies off the charts.

To put things in perspective, consider that guy in the tuberculosis sanitarium in Thomas Mann's novel The Magic Mountain. In his room, he keeps an X-ray image of his girlfriend's lungs. True, processing the film for that X-ray required resources, but if instead of gazing at the film, he'd persistently visited and venerated the same image on his PC, he could have very well exceeded the environmental burden of the X-ray film over the course of the relationship.

 

How Do I Offset My Carbon Footprint?

Hey Mr. Green,

I'd like to grow my own carbon credits by planting Douglas firs, which can live for more than 500 years, on my woodlot. How many do I need to plant to offset my carbon footprint?

--Larry in Vancouver, Washington

Planting trees is a splendid activity, but it's hard to plant your way out of global warming unless you have lots of land. And 500 years in the future is too remote for even Mr. Green to render a plausible prophecy. By then, your prospective Dougs might be thriving brilliantly, or driven to extinction, or exist only as DNA spirals in a spacecraft carrying your distant progeny on a galactic quest to find a planet to replace the one we wrecked.

So let's look a modest 50 years ahead instead. If you're an average American, you now emit 22 tons of carbon dioxide per year. In 50 years, you'll have pumped out 1,100 tons. To soak that up, you'd need to plant some 270 Douglas firs, assuming all of them make it to age 50. However, only 35 percent are likely to live that long, so you'd need to plant about 800 trees--requiring some 11 acres--to compensate for the firs that are bound to fall.

However, you can get by with planting fewer trees if you emit a lot less carbon dioxide than the average person. To find out where you stand, try the EPA's household emissions calculator at tinyurl.com/epacalc.