A low-carbon diet

People are learning and spreading the word about how to cut carbon dioxide emissions to save money and, maybe, the planet

William Blackwell cuts insulation for the basement of his Harvard home. Using less heating fuel is one way to reduce a house’s carbon emissions. (Globe Staff Photo / David Kamerman)

When Harvard resident William Blackwell decided to join the growing antiglobal-warming movement, he knew he had to enlist the help of his two teenage sons.

Blackwell knew that global warming is caused by the accumulation of greenhouse gases, mainly carbon dioxide in the atmosphere, and that cutting down on CO2 emissions is necessary to prevent Earth from overheating and causing all sorts of weather problems.

But how could he bring the concept home?

Happily for Blackwell and a growing number of environmentally conscious citizens, there is help from the Massachusetts Carbon Action Network, or MCAN, which encourages families to take simple, no-cost or low-cost steps to slash household emissions of CO2.

MCAN, which asks supporters to form "teams" for mutual support, has gained followers in several area communities, including Harvard, Lexington, and Medford. Its bible is an instructional book titled "Low Carbon Diet: A 30-day Program to lose 5,000 Pounds," with tips on ways to cut CO2 emissions - directly or indirectly - and how to organize others to do likewise.

The book states that the typical American home generates about 55,000 pounds of CO2 per year.

In the Blackwell household, the father explained to his sons how heating water for a 10-minute shower generates 4 pounds of CO2. Given the hard, cold numbers, the teenagers cut their 20 minutes under the spigot in half.

Now Blackwell, a software engineer, is reducing his household energy use by various means even more, as part of a statewide campaign he believes has promise.

"It has a great chance of success because of the way the program is easy to get your arms around," he said.

Such incremental household savings in CO2 output may seem puny when compared with the mammoth carbon footprint of the country. The United States is the world's heavyweight in CO2 production, according to scientists. In 1996, when significant national and international studies were conducted, Americans released some 1.4 trillion tons of CO2, according to the nonprofit Union of Concerned Scientists, contributing greatly to global warming and its effects. Much of the release is generated by the burning of fossil fuels - such as gasoline to power automobiles.

Still, households are a vital element in global warming, said Susan Altman of Medford, MCAN's outreach and programs coordinator. Moreover, she said, she believes ultimate change will come from the ground up.

"What the government sees people doing and asking the government to do is critical," she said. "The government acts when they feel compelled to do what their constituents need them to do."

Some of MCAN's tips for cutting back on direct household production of CO2 are obvious; for example, cutting back on the use of heating oil or electricity. But it also recommends indirect methods, such as abstaining from meat once a week, thereby saving the energy used to grow grain for animal feed, and to package and transport the meat.

Some cutbacks in CO2 emissions can lead to significant savings. For example, the MCAN book states that turning down the thermostat to 65-68 degrees during the day and 55-58 degrees at night can reduce yearly CO2 production by 1,400 pounds, while saving on bills for home heating oil, gas, or electricity.

"It seems the low-carbon diet had a broad basis of appeal," Altman said. "You didn't have to be converted to the climate-change agenda. You only had to care about your pocketbook."

About a year ago, MCAN started its campaign by signing up individuals from across the state. Altman said its first training session last June attracted more than 30 people representing 21 communities statewide; another session pulled in 15 people from 10 more communities in October.

In Lexington, which already boasted a vigorous environmental group called the Global Warming Action Coalition, the organizing was a natural.

Nancy Nolan, one of the coalition's founders, said she and others used the basic Carbon Action Network's organizing principle: One family joins a team of five, and recruits and trains five others, and each of them, five more, and so on, team by team. The Carbon Action Network's book suggests how each team can spend about 30 days preparing members to reduce their household carbon output by 5,000 pounds or more per year.

Nolan said the group's most important achievement with the campaign is pulling in like-minded environmentalists in religious congregations and schools.

This month, for example, the Lexington Hancock United Church of Christ, through the Hancock Environmental Action Team, has promoted the low-carbon diet as a Lenten offering. The church was set to hold three organizing meetings this month before church services.

And this is the second year in which all Lexington ninth-graders are required to participate in an earth sciences course that includes MCAN recommendations.

Teacher Avon Lewis said her students have performed energy audits of their homes, and now will work on suggestions for how their families could cut back.

Sanjana Singh, 14, who is taking the course, said that while her family was already environmentally conscious, she persuaded them to lower their CO2 production some more. For example, they now turn off the TV when not watching, she said.

Student Ben Feifke, also 14, said at first he wasn't that excited about the course, "but it's really opened my eyes to the problems we have that contribute to global warming."

In Harvard, a home-energy audit started last October persuaded Blackwell and other members of a team of five to do such things as insulating windows with clear plastic, and turning off computers, cellphones, and iPod chargers.

"We found the more we did, the more we wanted to do," Blackwell said.

After implementing household reductions of heating oil by 30 percent and electricity by 40 percent, group member Ericsson Broadbent III has gone even further.

A few years ago, Broadbent and his 15-year-old son attended a workshop at Yestermorrow, a Vermont program that trains people how to reduce greenhouse gases. There, the Broadbents learned how to convert a car to run on vegetable oil. For about $800, Broadbent said, they refitted a 1981 Mercedes, arranged for a steady supply of used cooking oil from a local restaurant, and invested in a filter to clean the oil.

Every day, Broadbent drove the vegetable-oil-powered Mercedes to work in Woburn, a roundtrip of about 90 miles, and then, after shifting to a new job in Burlington, used it for that daily 60-mile commute.

While some thought the car smelled like a moving vat of french fries, Broadbent said, he described as "like something good cooking."

Broadbent said he temporarily suspended use of the Mercedes because of the time it took to collect and filter the oil; he is now trying to develop a collective of like-minded drivers to share that work.

Similar campaigns are ongoing in Carlisle, Concord, and Groton.

Meanwhile, a team of six homeowners in Medford is trying to persuade their condominium association to reduce the 111-unit complex's CO2 emissions.

Fred Schlicher, one of the owners at the Old Medford High School Condominium, said that while making energy-saving adjustments to their own units, they have had inquiries from others who might want to do likewise.

The trailblazing team is investigating how to increase recycling for a presentation at the complex's annual meeting at the end of this month, Schlicher said.

Also in Medford, Temple Shalom this month started a team involving six households representing Arlington, Medford, Watertown, and Winchester, Altman said.

Among other benefits, dieters say, reducing carbon footprints can lead to lifestyle changes.

In addition to shorter showers, Blackwell said, his two sons are now walking to school every day instead of driving, even in poor weather. It's a healthier way to live, many would agree.

"They're very proud of it."

Connie Paige can be reached at cpaige@globe.com.