An industrial engineer’s version of the deconstruction of stuff is called Life Cycle Assessment, or LCA, a method that allows us to systematically tear apart any manufactured item into its components and their subsidiary industrial processes, and measure with near- surgical precision their impacts on nature from the beginning of their production through their final disposal.
LCAs had a prosaic start; one of the very first such studies was commissioned by Coca- Cola back in the 1960s to determine the relative merits of plastic and glass bottles and quantify the benefits of recycling. The method slowly spread to other industrial questions; by now a large and growing band of companies with national or international brands deploys the method somewhere along the way to make choices in product design or manufacturing—and many governments use LCAs to regulate those industries.
Life Cycle Assessment was created by a loose confederation of physicists and chemical and industrial engineers documenting the minutiae of manufacturing—what materials are used and how much energy, what kinds of pollution are generated and toxins exuded, and in what amounts—at each basic unit in a very long chain. In that dusty text the Riddle of the Chariot names a handful of components; today the LCA for a Mini Cooper breaks down into thousands of components—like the electronic modules that regulate electrical systems. These electronic modules deconstruct—like the chariot into its main parts—into printed wiring board, various cables, plastics, and metals; the chain leading to each of these in turn leads to a trail of extraction, manufacture, transport, and so on. These modules run dashboard systems, regulate the radiator fan, wipers, lights, and ignition, and manage the engine—and for each of these parts in turn the analysis can run into a thousand or more discrete industrial processes. In total, that petite car’s LCA entails hundreds of thousands of distinct units.
My guide in this terrain is Gregory Norris, an industrial ecologist at the Harvard School of Public Health. With degrees in mechanical engineering from MIT and aerospace engineering from Purdue and several years in the air force as an astronautical engineer helping build better space structures, Norris has impeccable credentials. But he readily concedes, “For LCA you don’t need to be a rocket scientist—I know, I was one. It’s mainly data tracking.
That meticulous analysis yields metrics for harmful impacts over an auto’s life cycle, from manufacture to junked car, for the raw materials consumed; energy and water depleted; photochemical ozone created; contribution to global warming; air and water toxicity; and production of hazardous wastes—to name but a few. An LCA reveals that in terms of global warming effluents, for example, everything in the car’s life cycle from manufacture to getting scrapped pales when compared to the emissions while it is driven.
When Norris walked me through a Life Cycle Assessment for glass packaging, like that for jams or pasta sauce, we ended up in a maze of interdependent linkages in a seemingly endless chain of material, transportation, and energy demands. Manufacturing bottles for jams (or anything in a glass container for that matter) requires getting stuff from dozens of suppliers—including silica sand, caustic soda, limestone, and a variety of inorganic chemicals, to name but a few—as well as the services of suppliers of fuels like natural gas and electricity. Each one of the suppliers makes purchases from or otherwise utilizes dozens of its own suppliers.
The basics for making glass have changed little since the time of ancient Rome. Today, natural gas- powered furnaces burn at up to 2,000 degrees Fahrenheit for twenty- four hours to melt sand into glass for windows, containers, or the monitor on your cell phone. But there’s far more to it than that. A chart showing the thirteen most important processes deployed to make glass jars revealed a system stitching together 1,959 distinct “unit processes.” Each unit process along the chain itself represents an aggregate of innumerable subsidiary processes, themselves the outcome of hundreds of others, in what can appear an infinite regression.
I asked Norris for some detail. “For example, let’s trace the production of caustic soda. That requires inputs of sodium chloride, limestone, liquid ammonia, a variety of fuels and electricity, and transport of those inputs to the site. Sodium chloride production in turn involves mining and water use, and inputs of materials, equipment, energy, and transport.”
Because “everything connects to everything,” Norris says, “we need to think in a new way.”
Another insight: the supply chain for a glass jar may consist of seemingly endless links, but these eventually hook back onto earlier links. As Norris explained, “If you go beyond the total 1,959 links in the glass jar’s supply chain, you loop into repeats—the chain goes on forever, but asymptotically.”
Norris gave a simple example of such repetitive loops. “It takes electricity to make steel, and it takes steel to make and maintain an electric power plant,” he explained. “You could truly say that the chain goes on forever—but it’s also true that the extra impacts of the upstream processes get smaller and smaller as you trace them farther and farther back.”
Making a glass jar requires the use of hundreds of substances somewhere upstream in the supply chain, each one with its own profile of impacts. There are around one hundred substances released into water and fifty or so into soil along the way. Among the 220 different kinds of emissions into the air, for instance, caustic soda at a glass factory accounts for 3 percent of the jar’s potential harm to health and 6 percent of its danger to ecosystems.
Another ecosystem threat, accounting for 16 percent of glassmaking’s negative impact, results from the energy for the furnace. Twenty percent of the negatives specifically for climate change are attributed to the generation of electricity for the factory that makes the glass. Overall, half the emissions from making a glass jar that contribute to global warming occur at the glass factory, the other half in other parts of the supply chain. The list of chemicals released into the air from the glass factory runs from carbon dioxide and nitrogen oxides at relatively high levels through trace amounts of heavy metals like cadmium and lead.
When you analyze the inventory of materials needed to make one kilogram of packaging glass, you get a list of 659 different ingredients used at various stages of production. These range from chromium, silver, and gold to exotic chemicals like krypton and isocyanic acid to eight different molecular structures for ethane.
The details are overwhelming. “That’s why we use impact assessment, where we can sum it all up into a few informative indicators,” says Norris. For instance, if you want to know what
carcinogens are involved in glassmaking, an LCA tells you the main culprit is aromatic hydrocarbons, the best known being VOCs, the volatile organic compounds that make the smell of fresh paint or a vinyl shower curtain a matter of concern. For glassmaking, these compounds account for about 70 percent of the process’s cancer-causing impact.
However, none of these are released directly from glassmaking at the factory; they are all somewhere else in the supply chain. Each one of the units of analysis in the glass jar’s LCA offers a point for analyzing impacts. Drilling down into the LCA reveals that 8 percent of the cancer-causing impacts come from releases of volatile organic compounds associated with constructing and maintaining the factory, 16 percent from producing the natural gas the factory uses to heat its furnaces, and 31 percent from making HDPE, high- density polyethylene for the plastic the glass is wrapped in for shipping.
Does this mean we should stop using glass jars for foods? Of course not. Glass, unlike some plastics, does not leach questionable chemicals into fluids and remains endlessly recyclable.
But as Norris took me through the highlights of that glass jar’s LCA, it hit me: all this was for a glass jar that is 60 percent recycled.
Exactly what, I asked Norris, is gained by that 60 percent? For one, he answered, the amount of new glass replaced by the recycled content saves about that proportion of weight in raw materials extracted, processed, and transported. “Of course you still need to process and transport post- consumer glass, but the net impact of glass recycling is still beneficial,” he reassured me, adding an example: “Every twenty- eight percent of recycled content saves five hundred gallons of water per ton of glass produced and avoids emissions of twenty pounds of CO2 to the atmosphere.”
And yet all those other impacts remain, despite the recycling. This transforms our notions of “green” from what seems a binary judgment—green or not into a far more sophisticated arena of fine distinctions, each showing relatively better or worse impacts along myriad dimensions. Never before have we had the methodology at hand to track, organize, and display the complex inter-relationships among all the steps from extraction and manu facture of goods through their use to their disposal—and summarize how each step matters for ecosystems, whether in the environment or in our body.
Every small step toward green helps, to be sure. But our craze for all things green represents a transitional stage, a dawning of awareness of ecological impact but one that lacks precision, depth of understanding, and clarity. Much of what’s touted as “green” in reality represents fantasy or simple hype. We are past the day when one or two virtuous qualities of a product qualify it as green. To tout a product as green on the basis of a single attribute—while ignoring numerous negative impacts—parallels a magician’s sleight of hand.
Consider a study of 1,753 environmental claims made for over a thousand different products plucked from the aisles of big- box stores. Some paper brands, for instance, focus on a narrow set of features, like having some recycled fiber content or chlorine- free bleaching, while ignoring other significant environmental issues for paper mills, such as whether the pulp comes from sustainable forestry or whether the massive amounts of water used are properly cleansed before return to a river. Or there’s the office printer that proclaims its energy efficiency but ignores its impact on the quality of indoor air or its incompatibility with recycled printer cartridges or recycled paper. In other words, it was not designed to be green from cradle to grave, but only engineered to tackle a single problem.
To be sure, there are relatively virtuous products, building materials, and energy sources. We can buy detergent without phosphates, install carpeting that exudes fewer toxins or flooring of sustainable bamboo, or sign up for energy that comes mainly from wind, solar, or other renewable sources. And all that can make us feel we have made a virtuous decision.
But those green choices, helpful as they are, too often lull us to more readily ignore the way that what we now think of as “green” is a bare beginning, a narrow slice of goodness among the myriad unfortunate impacts of all manufactured objects. Today’s standards for green ness will be seen tomorrow as eco- myopia.
“Very few green products have been systematically assessed for how much good they actually do,” says Gregory Norris. “First you have to do an LCA, and that’s rare.” Maybe thousands of products of any kind have gone through these rigorous impact evaluations, he adds, “but that’s a tiny fraction—millions are sold. Plus, consumers don’t realize how interconnected industrial processes are,” let alone their myriad consequences.
“The bar is too low for green products,” Norris concludes. Our current fixation on a single dimension of “green” ignores the multitude of adverse impacts that shadow even the most seemingly virtuous of items. As Life Cycle Assessment of just about anything shows, virtually everything manufactured is linked to at least trace quantities of environmental toxins of one kind or another, somewhere back in the vast recesses of the industrial supply chain. Everything made has innumerable consequences; to focus on one problem in isolation leaves all the other consequences unchanged.
As one industrial ecologist confided, “The term ‘eco- friendly’ should not ever be used. Anything manufactured is only relatively so.”
This shadow side of industry has been overlooked in the value chain concept, which gauges how each step in a product’s life, from extracting materials and manufacture through distribution, adds to its worth. But the notion of a value chain misses a crucial part of the equation: while it tracks the value added at each step of the way, it ignores the value subtracted by negative impacts. Seen through the lens of a product’s Life Cycle Assessment, that same chain tracks a product’s ecological negatives, quantifying its environmental and public health downsides at each link. This window on a company or product’s negative ecological footprint might be called the “devalue chain.”
Such information has strategic importance. Every negative value in an LCA offers a potential for upgrading and so improving the item’s overall ecological impacts. Assessing the pluses and minuses throughout a product’s value chain offers a metric for business decisions that will boost the pluses and lessen the minuses.
In a day when major players in every industry, and more and more consumers, are pressing for green, we would do well to understand the implication of improving impacts all along the supply chain and throughout a product’s life cycle. Green is a process, not a status—we need to think of “green” as a verb, not an adjective. That semantic shift might help us focus better on greening.