Ask Mr. Green: Hybrid or Natural-Gas Car?

Hey Mr. Green,

My husband claims that hybrids are greener than natural-gas-powered cars. What’s your take on this?  

—Naomi, in Berkeley, California

I’ve noticed that male declarations about vehicles are often not just wrong, but off by an order of chest-beating magnitude, but your hubby’s on target here. The hybrid is the clear winner because of its greater efficiency, as you can see by comparing the two types of Honda Civic. The natural-gas-powered Civic gets a fuel economy of the equivalent 31 miles of gasoline per gallon in combined city and highway driving, while producing 227 grams of greenhouse gas emissions per mile. By contrast, the hybrid Civic’s combined mileage is 44 mpg, with lower emissions of 202 grams per mile, according to the EPA. They are tied in EPA’s smog score, with an excellent 9. In terms of sheer energy consumption, the natural-gas Civic uses around 4,000 British thermal units (Btus) per mile, whereas the hybrid requires only about 2,820.

The Prius C hybrid, which won the 2013 greenest car of the year honors from the estimable American Council for an Energy Efficient Economy, beats them all, with a combined fuel efficiency of 50 mpg, while requiring 2,480 Btus per mile, and producing 179 grams per mile of greenhouse gas emissions. It scores just a notch lower on the smog index, garnering an 8.

Mr. Green Week: Wine and CO2?

To celebrate St. Patrick's Day, we're dedicating an entire week to our expert on all things emerald — Mr. Green. After a week of tips from our advice guy, you're sure to have a shamrock-green March 17. 

Hey Mr. Green,

I was touring Napa Valley's famed wineries with my sister and she got worried about the emissions from the fermentation. So how much carbon dioxide does it take to make all that two-buck Chuck?   

--James in Berkeley, California

Tell her to pour a glass and relax. Having a bottle of wine a day would total only about 50 pounds of carbon dioxide emissions per year (though there's no telling what that'd do to your liver). By contrast, the average car pumps out 10,000 pounds annually. So don't just avoid drinking when you drive — avoid driving to get your drink.

This is a post from Mr. Green's archives. Got a question? Ask Mr. Green!

READ MORE:

Sierra magazine's sustainable wine guide

Ask Mr. Green: How to Throw an EcoFriendly Kegger

5 Green Facts for St. Patrick's Day

Ask Mr. Green: What's the Best Oil Company?

Hey Mr. Green, 

What is the greenest oil company?

—Elizabeth, in La Mesa, California

It’s mighty tough to rate oil companies because of all the different ways that they can mess up the environment, and they are by nature more oil-slick brown than ecotopian green. Even their discussions of messes and methods have to be considered. For example, in ranking of oil behemoths, the environmental watchdog Greenopia looks at environmental reporting as well as five other factors: greenhouse gas emissions; production efficiency; oil spill efficiency; pursuit of alternative fuels, and stance on climate change. BP slid from first to fourth in their ratings mainly because of the catastrophic Deepwater Horizon oil spill in the Gulf of Mexico in 2010. Greenopia’s highest green ratings go to Sunoco, Shell, and Hess, in that order, with Valero and Citgo at the bottom of the barrel. Before Deepwater blew, BP also got top marks from Sierra because of its work on alternative energy and its openness about global warming at a time when the drill-babies at Exxon were lobbying against action on global warming and were funding think tanks that denied its existence. BP also slipped on its oil slick in Sierra's ratings.

Can I Build a Backyard Wind Turbine?

Hey Mr. Green,

I’d love to be able to build a wind turbine to generate electricity on my property. Is that even possible? And if so, what do I need to know? 

--Jesse in Half Moon Bay, California

Home wind energy is doable. But first, ask your zoning and building-code authorities whether a turbine of any size would be legal on your property. Local rules are all over the map: Some places might let you erect a turbine in a cemetery, while others won’t allow you to plant so much as a Porta-Potty on your premises. Also, understand that a turbine big enough to power a household typically needs at least an acre of space.

Next, to see about how much electricity you can expect to generate, try a tool like the one at solar-estimate.org and get turbine dealers’ estimates. A $20,000 turbine typically cranks out 3,500 kilowatt-hours per year. Homes in the U.S. consume an average of 12,000 kWh a year, though this can vary greatly; my three-hominid house uses only 2,800 kWh a year.

Installing your own device isn’t for the general handyperson, so unless you’re a pro, leave the job to the dealer (DIY gizmos are available, but their output is low.) Try for a turbine approved by the Small Wind Certification Council.

Tax credits and rebates (see dsireusa.org) can cut the cost of a turbine by thousands of dollars, depending on its location and utility and government policies. The IRS, for example, lets you knock 30% of a turbine’s price off your taxes.

Wind power’s not always a breeze, but with 20 million U.S. homes sited on an acre or more, it has some real residential potential.

Got an eco-question? Ask Mr. Green!

Ask Mr. Green: How Much Water Can I Save?

Hey Mr. Green,

How much water could be saved in a year in a household  of four, if we assume everyone has hair that is 20 inches long and they shorten it to 10 inches and that they each shampoo 3 times a week?  

—Duane, in Lincoln, Nebraska

We don’t have a reliable correlation between hair length and shower length, because of the many variables involved, e.g., different hair textures and densities, shampoos, personal habits, environmental attitudes, etc.

But what we do know is that showering requires a substantial torrent that accounts for 17 percent of all residential water use, or 1.2 trillion gallons per year in the United States, according the EPA. In light of last year’s drought and predictions of water shortages in no fewer than 36 states this year, briefer showers and better equipment are clearly a good idea.

Ask Mr. Green: Where Should Old Clothes Go?

Hey Mr. Green,

I've read that the average American dumps about 70 pounds of textiles (clothing, old carpets, etc.) into landfills each year. How do I recycle the stained and hole-ridden jeans that thrift stores won't take?

--Jesse in California

Americans dispose of more than 12 million tons of textiles annually, less than 25 percent of which is recycled or reused, dooming most secondhand clothing and carpets to a soggy afterlife crammed deep in a landfill.

Do Cleaning Products Have Dirty Secrets?

Hey Mr. Green,

How damaging to the environment are Scotch Brite pads and their ilk?

—Robbyn, in Novato, California

It all depends on which ilk of pad from which company. 3M’s Scotch Brite has joined the green parade by developing a line of environmentally friendly products such as its “Greener Clean” scouring pad. It’s made from natural agave fibers, unlike those composed of plastic and unspecified mineral substances, or metal pads infused with chemicals of unspecified provenance. Whether processing and transporting agave fibers has greater or lesser total environmental impact than making conventional pads is impossible to determine. I do fervently hope that such a use of agave, the source of tequila, is not diminishing the supply of this divine beverage.

Ask Mr. Green: Simmer or Nuke?

Hey Mr. Green,

I have about a quart of soup left over. Is it more efficient to reheat it on my gas range or in my microwave?

--Paul in Kalamazoo, Michigan

A microwave is a lot more efficient for reheating than a stovetop, since it takes 80% less energy to warm up relatively small amounts, according to the EPA. Although the microwave needs a lot of electricity, it's a relatively short burst of power. As the immortal Yogi Berra might have put it, "A watched pot never boils, but it boils quicker in a microwave."

While stovetops are less efficient, you can make regular gas or electric cooking more efficient by matching the size of the burner to the size of the pot—a 6-inch pot on an 8-inch burner can waste a goodly portion of a burner's heat—and by keeping a lid on unless the recipe forbids.

Though cooking accounts for only 3% of total U.S. greenhouse-gas emissions from residences, every bit we can cut is significant because we use so much more than we really need. Per capita, we now consume six times as much electricity and twice as much natural gas as we did in 1950. Whether our overall standard of living has improved correspondingly is open to debate.

Saving energy isn't just green but also massively cheaper than wasting power the way most households do. At your present utility rates, to heat that soup on the stove would cost you about three times as much as warming it in the microwave. As I always say, even if global warming didn't exist, there would be plenty of other reasons to save energy.

Got an eco-question? Ask Mr. Green!

A Real or Fake Christmas Tree: Which is Greener?

Hey Mr. Green,

Have you reached a conclusion on the real tree vs. artificial Christmas tree debate?

--Kathy in Winston Salem, North Carolina

I have indeed. The real tree is better for the environment than the fake tree. A real tree is a renewable resource, whereas a fake tree is usually made from plastic, which is derived from oil, a nonrenewable resource. The real tree can be recycled as mulch, compost, or wildlife shelter, whereas the fake tree can’t. The real tree does not contain harmful chemicals, whereas fake trees are often made with plastic polyvinyl chloride, whose manufacture releases highly toxic material. Plus, lead may have been added to stabilize the plastic. The real tree also absorbs carbon dioxide while it grows, doing its bit to fight global warming.

The belief that using real trees causes deforestation is mistaken. The fact is, real trees are farmed, often on marginal land that can't be used for other purposes. 

Ask Mr. Green: Low-Cost Wind Power or Hot Air?

Hey Mr. Green,

The Electric Reliability Council of Texas noted one day last summer that out of 10,400 megawatts of its wind-power capacity, wind was only producing 37 megawatts. Wow! 10,400 mWs of wind construction to get just 37. How the hell do you guys expect to power the nation with no coal- or gas-fired power plants when wind is so expensive and unreliable? I don't know about you, but I like my power on all the time.  

—Andy in Texarkana, Arkansas

Hang on, podner. Nobody claims we’ll instantly get by without coal or gas. The Sierra Club’s goal is a bit more modest and realistic: retire a third of the coal plants by 2020. Besides, your knock on windmills relies on fudged numbers, because you’ve singled out an unusually calm day. If you’d picked, say, March 28, 2012 instead, you’d’ve noticed that wind power topped 7,900 megawatts that day—24 percent of Texas’s total load. Already, 8 percent of the electricity generated in that massive state is from wind. Wind  power isn’t pricey, either. It costs about the same as electricity from new coal plants, averaging around $100 for your precious mWh, according to the Energy Information Administration. Iowa, for example, which gets almost 20 percent of its electricity from wind, enjoys a relatively low residential rate of less than 11 cents per kilowatt-hour. Even some nuclear-energy disciples have expressed surprise at the fast-dropping cost of wind power.