Dear EarthTalk: What is a low-carbon diet and is it good for losing weight or is it only about saving the planet? -- Jane Monroe, Scranton, PA
Not to be confused with a “low-carb” diet, which involves avoiding carbohydrates (bread, rice, pasta) as a way to lose weight or keep it off, a low-carbon diet—whereby you limit foods that generate a lot of carbon (CO2) emissions in their production and distribution—is indeed more about reducing your carbon footprint than your waistline. That said, proponents of a low-carbon diet say that eating with reduced greenhouse gas emissions in mind is healthier for us than the typical American diet whereby carbon-intensive meat, dairy and processed foods occupy too large a share of our overall food intake.
A recent study from the University of Michigan Center for Sustainable Systems backs up these assertions. Researchers correlated data from the National Health and Nutrition Examination Survey—a snapshot of what 16,000 Americans consumed over one 24-hour period—with information on the nutritional value and greenhouse gas impacts of different food items, concluding that the better a diet is for the planet, the better it is for our health. Furthermore, the 20 percent of Americans who eat what researchers consider a “high-carbon” diet (rich in red meat, dairy and exotic and processed foods) are responsible for almost half of the nation’s food-related CO2 emissions. The upshot is that changing the behavior and food choices of this small segment of the population could pay big dividends for public health and for reducing our overall national carbon footprint.
The concept of a low-carbon diet was first popularized in the U.S. by Bon Appétit Management Company, which runs more than 1,000 cafés in 33 states for corporations, universities and venues. Back in 2007, the company partnered with the non-profit Ecotrust to compile and conduct Life Cycle Assessments (LCAs)—measuring the amount of CO2 emitted during a given food product’s entire life cycle—for thousands of different foods. These LCAs became the basis for the “Food Scores” section of its EatLowCarbon.org website, which provides information to help people reduce their carbon footprints through food choices.
Besides launching EatLowCarbon.org, Bon Appétit’s managers also embarked on a five-year internal campaign to ratchet down the emissions generated by the company’s own operations and offerings by 25 percent. The company stopped buying air-freighted seafood, reduced its use of tropical fruit by half, shrank beef purchases by 33 percent and cheese by 10 percent while cutting food waste by one-third. Overall these moves shaved some five million pounds of carbon emissions per month off Bon Appétit’s contribution to global warming.
The fact that food and the systems to produce and distribute it are responsible for about a third of all greenhouse gas emissions means that everyone has a lot of potential for fighting global warming through sourcing locally produced and in-season foods to minimize emissions-intensive ‘food miles’, buying only as much as we can eat to reduce waste, and minimizing consumption of red meat, dairy and processed foods. In the case of climate change, if we don’t watch what we eat, it could really come back to haunt us.
CONTACTS: National Health and Nutrition Examination Survey, cdc.gov/nchs/nhanes/; “Greenhouse gas emissions and energy use associated with production of individual self-selected US diets”; https://iopscience.iop.org/article/10.1088/1748-9326/aab0ac; Bon Appétit Management Company, bamco.com; Ecotrust, ecotrust.org; Eat Low Carbon, EatLowCarbon.org.
Dear EarthTalk: I saw a news item about overhauling classic old cars with electric engines, and wondering if this can be done with any old car, such as my 1999 Subaru Outback? If this is feasible, maybe I should reconsider my plan of trading up for a new Prius. -- Tim St. Germain, Boise, ID
It’s true that there’s never been a better time to convert an old gas guzzling car into an emissions-free electric vehicle (EV), but some makes and models are better suited for a so-called “EV swap” than others.
Michael Bream of San Marcos, California’s EV West, which made news recently with its conversions of old VWs and Porsches into EVs, says you could convert a ‘99 Subaru—but EV Swaps are typically reserved for classic cars. “A newer Subaru has a ULEV certified (low emission) engine, so it’s not as bad a polluter as a classic car, and doesn't suffer from reliability and power issues that classic cars typically suffer from,” he says. “A typical conversion of a Subaru would cost about the same with parts and labor as a brand-new all-wheel drive Tesla Model 3, so unless your vehicle is extremely well loved, or you can't stand the thought of selling it, then it might be a better solution to buy or lease a new EV.”
EV West is one of a handful of garages across North America now specializing in EV conversions. Some others include: Zelectric Motors (San Diego, CA), ElectricGT (Chatsworth, CA), Make Mine Electric (Sebastopol, CA), Electric Vehicles of Washington (Bellingham, WA), Shockwave Motors (Russellville, TN), Epic Car Conversions (Toronto, ON) and Green Shed Conversions (Crystal River, FL).
If you don’t want to wait to get your car converted by one of these shops, you’ll just have to do it yourself (or find a local mechanic looking for an interesting project). Luckily lots of companies now sell EV conversion kits (Canadian Electric Vehicles, Electro Automotive, Wilderness Electric Vehicles, DIY EV, EV Source, Metric Mind Corporation, EV Drive) that include new engines, batteries and components. Expect to spend at least $8,000 on all the parts needed for the job (and tack on an additional ~50 percent more if you opt for longer-range lithium ion batteries). The labor will be up to you. DIYers should check out EVRater.com’s “How to Build Your own Electric Vehicle in 5 Easy Steps” or Mechanic Doctor’s “How to Convert Your Car to an Electric Vehicle” for step-by-step instructions. Meanwhile, California-based EV4U runs “3-Day Hands-On Conversion Workshops” near Sacramento for $495.
With a new base model Prius starting at $23k, you may well be better off doing the EV Swap on your old car. According to EVW, the operating costs of driving a Prius hybrid ($0.14/mile) are about four times what it costs to get around in an EV (whether native or a conversion). “In addition to the fuel savings, electric cars do not need oil changes, spark plugs, distributors, timing belts, etc.,” EVW adds.
What you won’t get is that new car smell or the nervous feeling of driving a brand-new car off the dealer’s lot. But you will get the satisfaction of knowing that you saved two tons of metal from the junk heap—and saved the world the trouble of sourcing materials for and building another brand-new Prius.
CONTACTS: EV West, www.evwest.com; Zelectric Motors, zelectricmotors.com; Make Mine Electric, makemineelectric.com; Electric Vehicles of Washington, www.electricvehicleswa.com; Epic Car Conversions, epiccarconversions.com; Green Shed Conversions, greenshedconversions.com; EVRater, evrater.com/build-your-own-ev; Mechanic Doctor, www.themechanicdoctor.com/convert-car-electric-vehicle; EV4U Workshops, ev4unow.com/EVWorkshops.html; Canadian Electric Vehicles, canev.com; Electro Automotive, electroauto.com; Wilderness Electric Vehicles, e-volks.com; EV Source, evsource.com; Metric Mind Corporation, metricmind.com; EV Drive, evdrive.com.
Dear EarthTalk: I’ve heard that China and other nations have gone gangbusters with reforestation projects that are ambitious enough to have a significant impact on cutting carbon emissions. Why aren’t we also doing this here in the U.S.? -- Mickie Infurcia, Hamden, CT
A recent Boston University (BU) study tracking satellite data of vegetation coverage found that the world is indeed getting greener overall, largely thanks to an ambitious reforestation program underway in China.
“China alone accounts for 25 percent of the global net increase in leaf area with only 6.6 percent of global vegetated area,” says lead researcher Chi Chen of BU’s Department of Earth and Environment. “This is equal to the net greening in the three largest countries, Russia, the United States and Canada, that together hold 31 percent of the global vegetated area.”
China’s reforestation efforts date back to the 1970s when the government started requiring every citizen over age 11 to plant at least three saplings every year to augment official government-backed reforestation projects. The result has been the planting of some 66 billion trees across some 12,000 miles of Northern China over the last few decades, with the so-called “Great Green Wall of China” expected to snake along some 2,800 continuous miles by 2050.
China isn’t the only country hell-bent on reforestation. Pakistan embarked on its Billion Tree Tsunami campaign in 2014 and is well on its way of achieving its goal of restoring healthy forests to some 350,000 hectares of degraded land. Meanwhile, Australia’s “20 Million Trees Program” aims to re-establish green corridors and urban forests across the country while mitigating climate impacts by facilitating the planting of 20 million trees by 2020. Another major reforestation effort with global impact is happening in Brazil, where the non-profit Conservation International is helping restore 30,000 of the hardest hit hectares across the so-called “arc of deforestation” in the Amazon rainforest as a key part of that country’s Paris climate agreement goal of reforesting 12 million hectares by 2030.
Here in the U.S., our forebears chopped down practically every tree they could until around 1920, but then we started to regain some of the lost tree cover over the next 40 years as abandoned farms reverted back to forest. Since then, we are barely net positive in forest cover as tree planting campaigns by the U.S. Forest Service and the non-profit Arbor Day Foundation have made up for losses from development and logging. That said, increased reforestation is not a major part of American efforts to meet climate mitigation targets given more practical ways we can achieve quicker overall emissions reductions.
Beyond the U.S., though, there is still lots of “low-hanging fruit” around the world in the form of other areas that would be good candidates for reforestation. The non-profit World Resources Institute (WRI) maintains the Atlas of Forest & Landscape Restoration Opportunities, which includes global overlay maps on current forest coverage, potential forest coverage, forest condition and human pressure on forest landscapes. According to WRI, upwards of two billion hectares of degraded or logged over forest lands around the world are ripe for restoration work if only we can muster the political will to make it happen.
CONTACTS: Chi Chen, sites.bu.edu/cliveg/people/doctoral-students/chi-chen/; EarthTalk’s “What Is The Great Green Wall of China?” earthtalk.org/green-wall-china/; Australia’s 20 Million Trees Program, nrm.gov.au/national/20-million-trees; Arbor Day Foundation, arborday.org; WRI’s Atlas of Forest & Landscape Restoration Opportunities, wri.org/applications/maps/flr-atlas.
Dear EarthTalk: Given all the advances in residential household efficiency, can you paint a picture of what the home of the future will look like? -- Jennifer C., Valmeyer, IL
No doubt, homes in the future, whether single family dwellings or apartments in larger buildings, will be much greener than what we are all living in these days. For starters, the use of sustainable, locally sourced (and ideally recycled) materials will be the norm, not the exception, so as to avoid the unnecessary emissions and resource consumption required to make new stuff and ship it around the world.
Homes of the future will be energy efficient. Part of this efficiency will come from better insulation, doors and windows to keep the heat/cold inside where you want it. The other part will come in the form of using renewable energy generated on-site, whether from rooftop photovoltaic solar panels, thin-film window treatments, solar shingles, micro wind turbines, kinetic energy harvesters, or other newfangled technologies. And all this self-sustaining energy will be stored in your own high-capacity batteries probably not so different from Tesla’s Powerwall array.
Homes of the future will also be smart. Your appliances, A/C, lighting, home security, motorized blinds, garage door openers and other systems will be connected to your network with controls available through apps over the Internet. And chances are, your future home will be smaller. The “tiny house” movement highlights how much homeowners can save on utility bills when space is limited. Efficiency can also be about use of space as much as about use of energy. While we won’t all live in tiny homes, downsizing will definitely continue to be “in.”
And what about outside your home? Don’t be surprised if your perfect lawn has been replaced by native plants attuned to the surrounding ecosystem. These hardy local plants won’t need chemical fertilizers, herbicides or pesticides to thrive. Rainwater from your roof will be collected in cisterns, with the resulting “graywater” used to irrigate your landscaping. A green roof or vertical garden could top it all off.
While the picture painted above may seem far-fetched, it’s really not, given that you could build a home that met all of the above criteria today for not much more than a conventional home. That said, it might be greener still to retrofit your existing old-school home with eco-friendly upgrades than to tear it down and build a new one, given the emissions associated with manufacturing, materials transport and assembly on a new structure. While the new home will be more efficient, it could take decades to “pay back” the “carbon debt” accrued by building from scratch.
Of course, all buildings run their course eventually, so when it is time to tear-down, it’s good to know there are plenty of green options out there to replace the old homestead. And with California adopting new building codes that go into effect in 2020 calling on all new construction of single-family homes and low-rise apartments to meet zero net energy standards (whereby they generate as much power from on-site renewables as they consume from the grid), the future may be here sooner than we imagined.
CONTACTS: Tesla Powerwall, tesla.com/powerwall; “Tiny Homes Are Big On Energy Efficiency,” ase.org/blog/tiny-homes-are-big-energy-efficiency; “CA Building Code Takes Big Step Toward Net-Zero Energy,” nrdc.org/experts/pierre-delforge/ca-building-code-takes-big-step-toward-net-zero-energy.
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