The report examines the fuel efficiency of 15 of the largest airlines in the U.S. An efficiency score of 1.00 corresponds to the industry's average fuel economy in a given year. Take a look at the chart below to see if you're with the right frequent flyer program:
Low-cost Allegiant Air took the bottom spot, with fuel efficiency 26 percent lower than Alaska, possibly due to the carrier's particularly old fleet of McDonnell Douglas aircraft. Nearly a third of the variation in efficiency can be attributed to aircraft technology, the study found. Other factors include seat density, cabin occupancy and ground operation practices.
Grounded airplanes traditionally use their engines to cool or heat cabins. Seattle-Tacoma International Airport announced plans for a revolutionary "central air" system that would pre-cool air for grounded planes. The measure is expected to save more than $15 million a year in fuel and cut CO2 emissions by 40,000 metric tons.
The data for the study was gathered from 2010 fuel-consumption reports given to the U.S. Bureau of Transportation Statistics. 2010 was chosen because it provided "a useful base year — post–global recession, prior to major mergers."
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Bike share programs have revolutionized transportation in some of the country's largest cities, like Washington D.C., Minneapolis, Miami Beach and Boston. For a daily or annual fee (usually around $7 or $75 respectively), users can check out a bike for about 30 minutes at a stand-alone kiosk, ride it around the city, and then check it in at any other kiosk in the system with no extra charge. The idea has been popular overseas since 2007 and there are now massive programs in cities like Paris (16,000 bikes), London (8,000), and Hangzhou, China (65,000). <a href="http://www.huffingtonpost.com/2013/05/27/citi-bike-share-program-launches_n_3342202.html" target="_blank">New York launched it's own 10,000-bike version, Citi Bike, earlier this year</a>. Many other cities (like Portland, Seattle, Detroit, Chicago, and Los Angeles) have programs in the works.
The Electric Car
Electric cars are finally starting to gain some traction and become reasonably affordable. <a href="http://www.businessinsider.com/cnbc-and-cnn-tesla-model-s-review-2013-2">The Tesla Model S</a>, <a href="http://www.huffingtonpost.com/2013/02/20/nyt-vs-tesla-feud-reaches-end-of-road_n_2720770.html">subject to some recent bickering</a>, has a range of about 275 miles on a single charge and a starting price tag around $50,000. <a href="http://www.chevrolet.com/volt-electric-car.html?seo=goo_|_GM+Chevy+Retention_|_GG-RTN-Chevy-Volt-BP-SN-Exact_|_Quotes+%26+Pricing_|_chevy%20volt%20price">The Chevy Volt</a>, an electric hybrid vehicle, has a range of about 35 miles before a gas engine kicks in. The all-electric <a href="http://www.nissanusa.com/electric-cars/leaf/index?dcp=ppn.63023882.&dcc=0.240189300">Nissan Leaf</a> gets an equivalent to 99 mpg. But the main concern is the youth of the industry. At home charging stations are recommended for most electric vehicles, but there isn't a <a href="http://www.huffingtonpost.com/2012/10/23/electric-car-charging-stations_n_2002448.html">widespread public system</a> that can rival gas stations, making long distance trips more difficult.
LEED Building Standards
The U.S. Green Building Council's <a href="http://new.usgbc.org/leed">Leadership in Energy and Environmental Design</a> system (LEED, for short) has revolutionized eco-conscious building initiatives across the globe. Companies looking to pump up their environmental track record are <a href="http://www.nytimes.com/2012/03/08/business/global/international-interest-grows-in-green-building-certification.html">spending time and money</a> to have their buildings certified green. LEED projects <a href="http://new.usgbc.org/leed/applying-leed">are in progress in 135 different countries</a>, and more than half of certified square footage is outside the U.S. A USA Today report criticized the system as <a href="http://www.usatoday.com/story/news/nation/2012/10/24/green-building-leed-certification/1650517/">being too lenient for some buildings</a>, which only need to get 40 points out of 100 to receive a certification.
Cheaper Alternative Energy
The cost for renewable energy <a href="http://www.mnn.com/earth-matters/energy/stories/renewable-energy-costs-falling">continues to fall</a> and is starting to become much more economically competitive with fossil fuels. New reports from the <a href="http://www.irena.org/home/index.aspx?PriMenuID=12&mnu=Pri">International Renewable Energy Agency</a> show the cost of solar falling more than 60 percent in the past few years alone. Increasing competition has helped push the price down, particularly with solar as U.S. and European manufacturers struggle to keep up with <a href="http://qz.com/41166/how-germanys-energy-transformation-has-turned-into-a-crisis/">the pricing of Chinese solar panels</a>. <a href="http://go.bloomberg.com/multimedia/wind-innovations-drive-down-costs-stock-prices/">Wind power has also gotten consistently cheaper.</a>
Reusable Bags/Plastic Bag Bans
Single-use plastic bags have been outlawed in a few major cities across the country like <a href="http://www.huffingtonpost.com/2011/12/19/seattle-plastic-bag-ban_n_1159154.html">Seattle </a>and <a href="http://www.huffingtonpost.com/2012/09/13/san-francisco-plastic-bag_n_1881889.html">San Francisco</a>, and others like <a href="http://www.huffingtonpost.com/2010/01/05/new-year-new-bag-fee-in-d_n_410344.html">Washington D.C.</a> have instituted a per-bag tax. <a href="http://www.nytimes.com/2008/01/09/world/asia/09iht-plastic.1.9097939.html?_r=0">China imposed a nationwide ban in 2008</a>. Why get rid of them? They're rarely recycled, <a href="http://www.epa.gov/osw/conserve/materials/plastics.htm">according to the EPA</a>. They take <a href="http://www.slate.com/articles/news_and_politics/explainer/2007/06/will_my_plastic_bag_still_be_here_in_2507.html">a really, really long time to break down</a>. And we humans use between <a href="http://www.nytimes.com/2007/04/01/weekinreview/01basics.html">100 billion and a trillion annually</a>. But people should be wary and keep grocery bags clean - a 2012 study found a connection <a href="http://www.huffingtonpost.com/2013/02/07/plastic-bag-ban_n_2641430.html">between reusable bags and a spike in E. coli infections.</a>
Sustainable fashion has been <a href="http://www.vogue.com/voguepedia/Eco_Fashion">in vogue and on the radar</a> since the early 1990s, but it's only gone mainstream recently. Synthetic fibers like polyester produce significantly <a href="http://www.huffingtonpost.com/2012/03/01/kingston-university-fashion-students_n_1312724.html">more carbon emissions than organic cotton</a>, and quite a few large brands were found to use <a href="http://www.huffingtonpost.com/2012/11/20/chemicals-in-fast-fashion-greenpeace-toxic-thread_n_2166189.html">some harsh chemicals to dye and manufacture</a> their garments. Either way, ethical and ecological clothing is catching on. H&M is the <a href="http://sustainability.thomsonreuters.com/2012/11/28/socially-responsible-company-hm-leads-the-way-as-worlds-biggest-organic-cotton-user/">biggest user of organic cotton</a> in the world, and brands like Nike and Zara have followed suit.
Better Ways To Throw Stuff Away
The average American throws about <a href="http://www.huffingtonpost.com/2012/08/21/food-waste-americans-throw-away-food-study_n_1819340.html">40 percent of their food </a> away every year, and nearly 100 cities have launched composting programs to try and keep it out of landfills. Curbside composting has spread across the country from uber-green San Francisco, which started their program 15 years ago and now collects <a href="http://www.motherjones.com/environment/2012/09/why-doesnt-your-city-have-curbside-composting">more than 600 tons of compost daily</a>. Of the 250 million tons of trash created in the U.S. in 2010, <a href="http://www.epa.gov/osw/nonhaz/municipal/index.htm">34 percent of it was diverted</a> to composting or recycling programs, according to the EPA.
Lightbulbs have changed quite a bit lately. Compact fluorescent lamps were introduced as highly efficient alternatives to traditional bulbs before 100, 75, 60 and 40-watt incandescent lightbulbs <a href="http://www2.epa.gov/cfl">are phased out of production by 2014.</a> But now, the new lighting revolution is in LED. These high-tech bulbs <a href="http://www.huffingtonpost.com/2012/04/23/philips-twenty-20-year-led-lightbulb-prize-department-of-energy_n_1445780.html">last upwards of 20 years</a> and use minimal energy. But, the new <a href="http://www.huffingtonpost.com/2012/04/24/how-much-pay-philips-lightbulb_n_1449444.html">Philips 10-watt bulbs cost $60</a>. Each. The good news is that the bulb is so efficient that if every 60-watt incandescent in the country were replaced, <a href="http://energy.gov/articles/department-energy-announces-philips-lighting-north-america-winner-l-prize-competition">$3.9 billion and 20 million metric tons of carbon emissions</a> would be saved in one year.
Community Gardens / Local Food Movement
Community gardening isn't really that new, but the local food movement is. The demand for <a href="http://seattletimes.com/html/pacificnw/2008817652_pacificplife15.html">plots in p-patches</a> or local green spaces has skyrocketed in the past few years as people opt out of GMOs and out-of-season produce (<a href="http://grist.org/locavore/local-haterade-authors-say-locavores-do-more-harm-than-good">which some argue is actually more carbon friendly</a>). Hyper-dense New York has <a href="http://www.nytimes.com/2012/11/01/garden/urban-gardens-grow-everything-except-gardeners.html?pagewanted=all">plans to reclaim vacant lots for urban agriculture</a> under Mayor Michael Bloomberg's <a href="http://www.nyc.gov/html/planyc2030/html/home/home.shtml">PlaNYC initiative</a>. The U.S. Department of Agriculture estimated the local food industry to <a href="http://www.huffingtonpost.com/2011/11/14/locally-grown-food_n_1092146.html">be $4.8 billion in 2008 and upwards of $7 billion in 2011</a>.
Death isn't the best thing for the environment. Cremation sends more than <a href="http://www.huffingtonpost.com/2012/09/13/green-funerals-options_n_1880096.html">6.8 million tons of carbon emissions</a> into the atmosphere every year, caskets take a long time to biodegrade and burial leads to methane emission (<a href="http://epa.gov/climatechange/ghgemissions/gases/ch4.html">the second most prevalent greenhouse gas</a>). But <a href="http://www.huffingtonpost.com/2008/04/22/green-funerals-how-to-mak_n_97940.html">environmentally-friendly burial options</a> are becoming more prevalent. Wicker and cardboard coffins can replace traditional wood, and dry ice is used rather than formaldehyde. <a href="http://www.greenburialcouncil.org/finding-a-provider/SearchProviderSearchForm?mainsearch=Caskets&mainsearchField=OrgProductType&action_searchproviders=Search">And green burial services</a> are popping up around the globe to curb post-mortem emissions.