Eating well without destroying the climate

Published on CommonDreams (Nov. 28, 2019)

By Kumar Venkat

As you sit down to eat a holiday dinner with family or friends this year, the Earth’s climate may be the farthest thing from your mind. But if you are looking for a good New Year’s resolution in a few weeks, you can’t go wrong with climate-friendly eating. The links between food and climate are significant but fairly simple to understand. It is not difficult to eat well without destroying the climate.

Perhaps the biggest climate decision around food that most of us will make is the choice of proteins. Red meats like beef and lamb have a dramatically higher carbon footprint than plant-based options such as beans or tofu. For an equal supply of protein, beef produces 20–25 times as much greenhouse gas emissions on average as beans, and about 12 times as much as tofu. Chicken and turkey, on the other hand, are much more benign, producing only 3–6 times the emissions of plant-based proteins.

The average American consumes 275 pounds of red meats and poultry per year, which generates about a metric ton of greenhouse gas emissions during production. To put this in perspective, this is six percent of annual US per-capita emissions. Just replacing beef with chicken would cut these emissions in half and is one of the easier solutions if you are not ready to go vegetarian or vegan. For those willing to try meat substitutes, plant-based burger patties generate only a tenth of the emissions of ground beef.

When greenhouse gas emissions of food products are calculated over the full product life cycles, emissions from transportation are generally less than 10 percent of total emissions and therefore not very significant. Moreover, local food production often suffers from inefficient distribution — and higher emissions per pound of food — compared to the highly streamlined logistics of long-distance goods transport.

So you don’t have to buy local to be climate-friendly as long as you are not getting fresh foods like salmon that are air-freighted.

Life-cycle assessments of organic production point to a number of common inefficiencies such as lower yields and higher on-farm energy use. Increased soil carbon sequestration remains the one clear advantage in the first few decades after converting conventional croplands to organic production. But the lower yields would have to be made up through increased food production and land-use changes elsewhere.

Net emissions would likely be greater with any large-scale move to organic production, so eating organic is more a matter of personal preference than a climate solution.

Food processing and packaging do add to a product’s life-cycle emissions. Since plant-based foods start out with low emissions, they see a larger relative impact than animal foods. Processing is likely to be more energy-efficient and less wasteful than home cooking but freezing can more than double the emissions of plant-based foods. Packaging typically contributes less than ten percent of total product emissions in most cases, but it could double the emissions of processed fruits or vegetables that are canned or bottled.

Neither of these impacts is large enough for consumers to avoid processed and packaged foods entirely on the basis of climate.

Finally, the food that we don’t eat has a climate impact from the wasted production, processing, transport and disposal. Nearly 30 percent of the food produced in the US is wasted each year, and over 60 percent of that is consumer waste. This works out to about 240 pounds of avoidable waste per person and contributes 1–2 percent to per-capita emissions. But not all food waste is equal.

Wasted animal foods have 3.5 times the climate impact of plant-based foods on average, so it helps to start by focusing the waste reduction on high-emission foods.

Rather than taking on a laundry list of small actions around food and climate, it might be easier — and more satisfying — to commit to a couple of big things in the new year that can really move the needle. After years of studying the climate impacts of foods, I can’t think of anything more impactful than our choice of proteins, followed by waste reduction. Everything else that we can do for food sustainability is icing on the cake.

Oregon must target climate change, not plastic bags

Published in The Oregonian (Nov. 17, 2019):

By Kumar Venkat

My local grocery store recently decided that it would no longer offer single-use carryout plastic bags, presumably to get a head start on Oregon’s upcoming ban on such bags. I, for one, had always saved and reused these bags, usually as garbage can liners, so I got at least two uses out of them. I now buy garbage bags that are made of heavier plastic and hence create more carbon emissions than the flimsy grocery bags.

Data from California shows in fact that purchase of plastic trash bags spikes dramatically when disposable plastic bags are banned. That is not the only unintended consequence. Some customers end up taking home paper bags that have a demonstrably higher carbon footprint than plastic bags of the same carrying capacity.

Consider the best-case scenario: Even if every shopper in this country replaced all plastic grocery bags with reusable bags and purchased no additional trash bags, the emissions savings would be minuscule. Single-use plastic bags already have the smallest carbon footprint to produce as many studies have shown. All things considered, the choice of bags would make essentially no difference in the battle against climate change.

But isn’t tackling the problem of plastic pollution in the oceans one of the aims of this ban? Yes, but less than 1 percent of the world’s plastic waste that is litter or improperly disposed of originates in the United States. We are just not a big enough plastics polluter to help solve this problem.

A year after the ban went into effect in California, the number of plastic bags in the state’s beach litter dropped by more than half, but the actual amount of bag waste saved was less than 750 pounds. We can expect to save significantly less than that in Oregon, which has about one-tenth of California’s population.

Waste reduction in and of itself is a good thing, but we should just be aware that this particular ban might not yield a return proportional to the combined efforts of Oregonians to comply with it. It is a small environmental victory to savor after the failure of the cap-and-trade bill in the summer, but by no means a replacement for meaningful action.

The real existential threat to Oregon and the nation is climate change. The United States is the second largest carbon polluter in the world, so it is logical for states to take the lead on climate given a lack of response at the federal level.Share your opinionSubmit your essay of 500-700 words on a highly topical issue or a theme of particular relevance to the Pacific Northwest, Oregon and the Portland area to Please include your email and phone number for verification.

The Oregon climate bill failed largely because of a lack of public appetite for higher fossil fuel prices. Even though the bill would have provided refunds to lower-income Oregonians, there was no way to fully mitigate the disproportionate share of the burden placed on individuals and businesses in rural areas. We need to bring a majority of Oregonians on board by addressing real concerns like these.

Some ideas to consider: exempt the trucking industry for some number of years by offsetting their fuel cost increases through refunds (after all, we all benefit from the products the trucks deliver), help rural Oregonians purchase more efficient vehicles, and perhaps provide other refunds or tax credits in the short term to close the urban-rural divide on this issue.

Climate legislation is going to be much more difficult than banning plastic bags, but climate is the real crisis crying out for a solution.

Advice for the climate-conscious consumer: Don’t sweat the small stuff

Published in the Los Angeles Times (Nov. 5, 2019:)

By Kumar Venkat

It can be confusing for climate-conscious consumers to sort through all of the carbon-reduction options out there in search of the ones that can truly make a difference. Even with a background in carbon footprint analysis, I still find it tricky to separate the good ideas from the bad.

I have learned to follow a simple rule of thumb that helps me cut through all the climate-related noise: Don’t sweat the small things when it comes to climate change. Focus your energies and investments on a few big actions that you can sustain over the long term.

But common misconceptions about what can move the climate-change needle make it harder for consumers to make the right choice.

In 2014, California became the first state to pass legislation to ban single-use plastic bags at retail stores. The question of whether paper or plastic is better for the environment has become largely irrelevant as a growing list of states and cities have banned all single-use plastic carryout bags. Yet this high-profile movement does little to reduce the nation’s total carbon emissions.

Even if every shopper in the U.S. switched from plastic to reusable bags, we would reduce our annual national emissions by only 0.02%.

Making a point of purchasing locally produced food is another common action that provides little climate benefit. Much concern has been expressed over the years about “food miles” — the distance that food travels from farms to consumers — and the associated emissions from transportation.

However, transportation emissions are generally much smaller than those from production, so consumers would be better off focusing more on how foods are produced. For example, the carbon footprints of animal-based foods can be two to 20 times larger than those of plant-based foods.

Even when emissions from production are low — as they are with many fruits and vegetables — transportation alters their carbon footprint in a counterintuitive way.

Long-distance transportation via semi-trailers is generally more efficient than local transportation in smaller vehicles. Farm-to-retail transportation emissions of local farmers market produce can end up being more than double that of similar supermarket produce.

In addition, emissions from packaging materials are rarely large enough to justify making purchasing decisions based on how a product is packaged. Packaging typically accounts for less than 10% of the total emissions for most food products, and significantly less than that for durable goods.

Sometimes it helps to put the action you want to take in perspective. The American Cleaning Institute, an organization that represents the cleaning products industry, recently estimated that a household could cut its emissions by 864 pounds of carbon per year by washing four out of five loads in cold water. That number sounded impressive until I calculated that it works out to about one-half of 1% of the annual carbon footprint for a family of four.

Even if every family in America adopted the cold-water washing method, national emissions would only be reduced by less than 1%.

Consider the widely held belief that organic farming is better for the climate. Multiple studies have shown that net emissions would be higher in the long run with organic production due to lower yields. I buy some organic produce to minimize the pesticides my family ingests, but I have no illusions about helping the climate when I do that.

But consumers are not powerless. Significant emission reductions are possible in the areas of transportation and electricity, which are responsible for more than 60% of net U.S. greenhouse gas emissions.

typical passenger vehicle generates about 4.6 metric tons of carbon dioxide per year, which accounts for a quarter of U.S. per-capita carbon emissions. Driving the vehicle 20% fewer miles a year would translate to a 5% reduction relative to per-capita emissions. If public transportation is substituted for half the miles driven, it results in a 15% emission reduction.

Driving an electric vehicle can cut emissions by 10 to 20%. Eliminating a single coast-to-coast flight can save nearly 4% relative to per-capita emissions, but these savings only become significant when enough people avoid flying and fewer planes are in the air.

Many electric utilities in California and elsewhere offer green-energy programs that can supply 100% of a home’s electricity with renewables like solar or wind energy for less than an additional penny per kilowatt-hour. This inexpensive option could cut per-capita emissions an average of 10% while helping to boost investments in additional renewable energy capacity.

Big consumer commitments like these really could have an effect on climate change. Just think of the less-impactful moves you make to “save the environment” as a bonus.

Kumar Venkat is a technologist based in Portland, Ore. As the founder of CleanMetrics Corp., he helped companies quantify and reduce greenhouse gas emissions.