Plastic Packaging Offers Significantly Reduced Greenhouse Gases

Woman grocery shopping

Previously published in Plastics Engineering and posted with permission from the Society of Plastics Engineers.

Common Assumptions about Plastic Packaging… Debunked

We’ve all read it in the newspaper. Seen it on TV news reports. And heard it from our friends and neighbors: Plastic packaging is a big waste of energy because it’s made from crude oil and natural gas. And if plastic packaging is a waste of energy, surely it also must be creating egregious amounts of greenhouse gas emissions.

Well, not according to two large studies, one done in Europe in 2010 and another completed in North America in early 2014. Read on for a few facts that rebut some common (and incorrect) assumptions about plastic packaging…

What Life Cycle Category Reviews Tell Us about Plastic Packaging

The well-respected research firm Franklin Associates in March released a study with the lengthy but apt name: “Impact of Plastics Packaging on Life Cycle Energy Consumption & Greenhouse Gas Emissions in the United States and Canada.” The study compared the weight, energy requirements, and greenhouse gas emissions of plastic packaging to packaging made with alternative materials, in six categories:

  • caps and closures,
  • beverage containers,
  • other rigid containers,
  • carrier (or shopping) bags,
  • stretch/shrink wrap, and
  • other flexible packaging.

The results, similar to those of the 2010 study done in Europe, are striking.

The study found that for the baseline year 2010, replacing all plastic packaging with non-plastic alternatives for these six types of packaging in the United States would:

  • require 4.5 times as much packaging material by weight, increasing the amount of packaging used in the U.S. by nearly 55 million tons or 110 billion pounds;
  • increase energy use by 80 percent;
  • result in 130 percent more global warming potential.

These numbers, simply put, are extraordinary.

  • Weight: Americans generate approximately 250 million tons of waste each year – an additional 55 million tons of packaging would increase overall waste generation by 22 percent! That’s the equivalent of the weight of more 169,000 Boeing 747 jumbo jets.
  • Energy Use: an 80 percent increase in energy use is equivalent to the energy from nearly 91 oil supertankers;
  • Global Warming: a 130 percent increase in global warming potential is equivalent to adding 15.7 million more cars to our roads.

Similar calculations are available for the Canadian market.

“This study demonstrates that plastic packaging makes a significant contribution to sustainability by dramatically reducing energy use and lowering greenhouse gas emissions,” said Steve Russell, vice president of the American Chemistry Council’s (ACC) Plastics Division, which commissioned the study, along with the Canadian Plastics Industry Association.

Lighter Weight is Key

How can this be? If plastics are made from energy resources, surely they must use more energy than alternatives, and thereby contribute to greater greenhouse gas emissions. That’s the common assumption… but is it true?

Apparently not. This and other studies have found that the weight of packaging material appears to be the primary (but not sole) factor in determining many of the environmental impacts of packaging, such as energy use.

The amount of energy used to make a product or package can be a small part of overall energy use – in fact, the product or packaging actually can save energy use over its lifetime. Homeowners are familiar with this concept: when buying a new washing machine, the focus is not on how much energy it took to manufacture but on how much energy it will use (or save) during operation.

Experts can calculate the total energy “footprint” of a washing machine over its entire life cycle, as well as other things – such as lightweight plastic packaging.

Waste expert Bob Lilienfeld sums it up well in his analysis of the Franklin Associates study. He is the editor of the widely read newsletter The ULS Report (ULS = Use less Stuff;

“There is a simple, yet profound scientific explanation as to why plastics performed so well. In general, plastics have a higher strength-to-weight ratio than other materials, and thus a greater carrying capacity: You contain more product with less plastic packaging than with other materials. Using less reduces material usage, as well as energy consumption throughout the supply, distribution, and value chain.”

In other words, the very nature of plastics – lightweight yet strong – makes them ideal for all sorts of packaging plus helps minimize the environmental impact of the packaging.

So in a nutshell: lightweight plastic packaging delivers more goods with significantly less waste, energy use, and global warming potential.

“Keep the Molecule in Play”

Bob Lilienfeld also concludes that the “best way to generate maximum value from virtually all packaging materials is to ‘keep the molecule in play’. This means we should strive to reuse and recycle as much packaging as possible, and not place undue emphasis on a material’s ability to biodegrade or be composted. While there may be specific applications in which this functionality is desirable, composting and biodegradation of materials such as paper and plastic can actually lead to increased potential for climate change…”

“This research and its predecessor study indicate that it would be better to reuse and recycle the material, or recover it for energy…”

Well said. That’s one reason why, according to ACC’s Steve Russell, “America’s plastics makers are working to enhance plastics’ environmental performance after use by increasing recycling and recovery while supporting efforts to prevent litter.”

And that work is paying off. Two recycling examples:

  • More than 94 percent of Americans today can recycle bottles and caps locally, and more than 60 percent can recycle other types of rigid plastic containers and lids.
  • More than 91 percent of Americans today can recycle plastic bags locally at one of 18,000 locations across the U.S., primarily major grocery and retail chains, and another 71% can recycle other types of flexible polyethylene wraps.

Plus numerous companies are developing innovative, large-scale technologies to convert non-recycled plastics into fuels that one day could power our cars, trucks and communities.

Can Common Assumptions Change?

Can scientific studies help demonstrate “that plastics and plastic packaging play a far more positive role in the quest for sustainability than most people recognize,” as Lilienfeld concludes?

Who knows? As mentioned above, many Americans assume that plastic packaging is wasteful, according to public opinion research. Popular media have helped spread that assumption. But as media scholar Marshall McLuhan once noted: “Most of our assumptions have outlived their uselessness.”

Perhaps this assumption will, too.