Reference: nanozeo.WebLCA.net trainings, Ecoinvent website, ISO 14040/44/14064/14067 standards, EU-Product Environmental Footprint (PEF), CDP/SBTi requirements, Dr. CP Tung and Dr. Chunpo Hung's SSBTi/TFF/SFIT trainings, CLCD/CPCD/ELCD databases, and many thanks and special honor to: H. Scott Matthews, Chris T. Hendrickson, and Deanna Matthews, Life Cycle Assessment: Quantitative Approaches for Decisions that Matter, 2014.
ESG and Footprints Based on Life Cycle Assessment: One for All Approaches to SBTi
Podcast Audio for Deep Dive Discussion for Overview.
Expanded Explanation: Defining the Concept of a Life Cycle and Its Stages
A life cycle refers to the sequence of stages a product, system, or organism goes through from its beginning to its end. This concept is widely applied in both natural and human-made contexts. In nature, life cycles are evident in processes such as the metamorphosis of a butterfly, the water cycle, or the growth of plants through seasonal changes. Similarly, manmade products also follow a life cycle—from raw material extraction to manufacturing, usage, and finally disposal or recycling. Understanding life cycles allows for better decision-making in resource use, sustainability, and environmental impact.
Manmade Product Life Cycles
While natural life cycles occur as part of ecosystems, human-created products also undergo distinct stages. Consider the journey of an aluminum can: it starts as raw bauxite ore, which is extracted, refined, and processed into aluminum sheets before being formed into a beverage can. After use, the can is either discarded in a landfill or recycled into a new product. Another example is a cellphone, which consists of materials sourced from various parts of the world, assembled into a finished device, used by a consumer, and then either resold, donated, or discarded. These examples illustrate the continuous and interconnected nature of life cycles in both natural and industrial contexts.
Stages of a Life Cycle
The life cycle of a product typically includes the following key stages:
Raw Material Extraction (Resource Acquisition) – This is where materials such as metals, plastics, or organic substances are sourced. For example, metals for electronics come from mining, while wood for paper products comes from forestry.
Material Processing & Manufacturing – Once raw materials are obtained, they are refined and processed to create intermediate or final products. This stage includes energy-intensive activities such as metal refining, chemical synthesis, and factory assembly.
Product Use & Consumption – After manufacturing, the product reaches the consumer or is integrated into a system. This phase can range from a short single-use product (e.g., a plastic bag) to long-term use (e.g., a car or an appliance).
End-of-Life Management (Disposal, Recycling, or Repurposing) – When the product is no longer useful, it enters its final stage. Some products are disposed of in landfills, while others are repurposed, refurbished, or recycled to extract valuable materials and reduce waste.
Life Cycle Perspectives: Cradle-to-Grave vs. Cradle-to-Cradle
Different approaches exist for evaluating product life cycles:
Cradle-to-Grave: This perspective considers the full journey of a product, from raw material extraction to its final disposal, without reuse or recycling.
Cradle-to-Gate: This focuses only on the stages up to when the product leaves the factory, excluding its use and end-of-life phases.
Cradle-to-Cradle: A more sustainable approach that designs products for continuous reuse and recycling, minimizing waste and resource depletion.
By applying life cycle thinking, industries and policymakers can make informed decisions about product sustainability, resource efficiency, and environmental impact mitigation. Understanding the full cycle of a product allows for strategic choices that minimize negative effects and promote circular economy practices.
2
Illustrate complexity
Show the complexity of life cycles for simple products.
Expanded Explanation: Illustrating the Complexity of Life Cycles for Simple Products
At first glance, the life cycle of a simple product may appear straightforward. For example, a paper napkin or a plastic water bottle seems to follow a simple path: manufactured, used, and discarded. However, when examined through the lens of Life Cycle Assessment (LCA), even the most basic products reveal a complex web of interconnected processes, materials, energy flows, and environmental impacts.
Case Study 1: A Simple Paper Napkin
A paper napkin seems like an uncomplicated disposable product, but its life cycle is surprisingly intricate:
Raw Material Extraction:
The journey starts in managed forests or tree plantations, where trees are grown specifically for pulp production.
Logging operations require heavy machinery, which burns fossil fuels and emits CO₂.
Trees are transported to paper mills, consuming additional energy in transportation.
Material Processing & Manufacturing:
Wood is pulped using mechanical and chemical processes, involving chemicals like bleach and sulfur compounds that contribute to water pollution.
The pulp is formed into thin sheets using large amounts of water and electricity.
Napkins are cut, packaged in plastic wrapping, and distributed to retailers.
Product Use & Disposal:
Unlike a reusable item, a napkin is single-use, meaning it is disposed of immediately after use.
If thrown in a landfill, it contributes to organic waste but decomposes relatively quickly.
If incinerated, it may generate air pollution and carbon emissions.
Despite being a low-cost, disposable item, a napkin’s life cycle involves complex energy flows, chemical processing, and environmental considerations across multiple stages.
Case Study 2: A Plastic Water Bottle
A plastic water bottle is another seemingly simple product, but its life cycle spans multiple industries and global supply chains:
Raw Material Extraction & Processing:
The primary ingredient, polyethylene terephthalate (PET), is derived from crude oil and natural gas.
Oil extraction, refining, and polymerization processes require energy-intensive operations, generating greenhouse gas emissions and toxic waste byproducts.
Manufacturing & Distribution:
Plastic is molded into bottle shapes, filled with water, and sealed.
The bottle is shipped globally, consuming fuel for transportation.
Consumer Use & End-of-Life Scenarios:
Recycling: If collected and properly processed, plastic bottles can be recycled into new plastic products or polyester fibers.
Landfill Disposal: If discarded improperly, plastic can persist for hundreds of years in the environment.
Ocean Pollution: Many bottles end up in marine ecosystems, breaking down into microplastics that harm wildlife.
Even a single-use plastic bottle embodies complex supply chains, energy demands, and long-term environmental challenges.
Why Do Simple Products Have Complex Life Cycles?
Even for basic consumer goods, multiple hidden factors contribute to life cycle complexity:
Multi-Stage Production: The materials often go through several transformation steps before becoming the final product.
Global Supply Chains: Raw materials may be extracted in one country, processed in another, and assembled elsewhere, increasing transportation impacts.
Energy & Chemical Inputs: Manufacturing often requires multiple resources, including electricity, water, and various chemical treatments.
Multiple End-of-Life Scenarios: Products may be recycled, incinerated, landfilled, or contribute to pollution, affecting long-term environmental sustainability.
By recognizing this complexity, we can develop better strategies to reduce environmental harm, improve product design, and promote sustainable alternatives that minimize waste and resource consumption.
Environmental issues, much like physical products, are complex and require broad, systems-level thinking to fully understand their causes and consequences. Many past environmental decisions were made with narrow perspectives, leading to unintended consequences that could have been avoided with a more comprehensive approach.
A systems-level perspective considers the entire life cycle of a product, process, or policy—rather than just a single phase—ensuring that solutions do not create new environmental problems elsewhere. This kind of thinking is essential for making informed decisions that balance economic, environmental, and social sustainability.
The Complexity of Environmental Problems
Historically, industrial production and environmental management were treated as linear systems: raw materials were extracted, products were manufactured and used, and waste was disposed of. However, this "end-of-pipe" approach, which focuses only on treating waste and emissions after they occur, has proven inadequate.
1. Hidden Environmental Costs
Many environmental problems are not immediately visible. For example:
A power plant may appear clean because it has air pollution control equipment, but if it still emits high levels of CO₂, it contributes significantly to climate change.
Electric vehicles (EVs) were initially promoted as "zero-emission vehicles," but a life cycle analysis (LCA) showed that their overall environmental impact depends on:
Electricity sources (coal-fired vs. renewable energy).
Battery production, which requires mining rare metals with serious environmental consequences.
2. Interconnected Systems & Global Impacts
Environmental problems do not occur in isolation:
Deforestation for agriculture affects carbon sequestration, biodiversity, soil erosion, and water cycles.
Plastic waste reduces food spoilage and transport emissions but contributes to marine pollution and microplastics that harm ecosystems.
The ozone depletion crisis caused by chlorofluorocarbons (CFCs) required global cooperation (Montreal Protocol) to be resolved.
3. Time-Delayed Effects
Some environmental problems take decades to manifest:
Climate change results from CO₂ emissions that persist in the atmosphere for centuries.
Acid rain, caused by sulfur dioxide (SO₂) emissions, was not widely recognized until ecosystems and water bodies had already suffered extensive damage.
Why Systems Thinking is Necessary for Environmental Solutions
Adopting a life cycle and systems approach helps policymakers, businesses, and consumers make better choices that account for long-term environmental trade-offs.
1. Avoiding Unintended Consequences
When decisions are made with a narrow focus, they often create new environmental issues elsewhere:
Lead-Acid Electric Vehicles (1990s): California’s push for zero-emission vehicles (ZEVs) focused only on eliminating tailpipe emissions. However, an LCA revealed that the electricity demand for charging and the lead pollution from battery production and recycling outweighed the benefits.
Compact Fluorescent Lamps (CFLs): Promoted as an energy-efficient alternative to incandescent bulbs, CFLs contained mercury, creating hazardous waste disposal challenges.
A systems approach considers all life cycle stages, identifying potential trade-offs before large-scale implementation.
2. Identifying Environmental Hotspots
Life cycle thinking allows us to pinpoint which stages of a product's life cause the most harm, so we can focus mitigation efforts on high-impact areas.
Automobile LCA Example:
While manufacturing a car consumes materials and energy, the majority of emissions come from fuel consumption during its operational phase.
This insight has led to fuel efficiency standards, hybrid technology, and electrification as strategies to reduce lifecycle emissions.
Plastic vs. Paper Bags Debate:
Paper bags use renewable materials but require energy-intensive production and heavy transportation emissions.
Plastic bags, though derived from petroleum, use less energy in manufacturing and transport but create long-term waste management challenges.
Conclusion: The solution depends on reuse rates, recycling infrastructure, and disposal methods—not just material choice.
3. Supporting Circular Economy and Sustainable Development
Instead of a linear "take-make-dispose" model, a systems-level approach encourages circular economy strategies, where materials are reused, recycled, or repurposed.
Cradle-to-Cradle Design: Products are designed to have multiple life cycles through recycling, remanufacturing, or biodegradable materials.
Sustainable Materials: Companies are shifting toward bio-based plastics, aluminum recycling, and renewable energy to reduce life cycle emissions.
Extended Producer Responsibility (EPR): Some industries (e.g., electronics) now take back old products for responsible recycling.
Summary: Thinking Beyond the Obvious
To truly address environmental issues, systems-level thinking is essential. Instead of focusing on isolated solutions, we must examine entire product and environmental life cycles, from resource extraction to final disposal.
By adopting life cycle thinking, we can: ✅Make more informed policy and business decisions. ✅Identify trade-offs before implementing environmental solutions. ✅Avoid shifting environmental burdens to another stage or region. ✅Promote circular economy strategies that minimize waste and maximize resource efficiency.
Without systems-level thinking, well-intended decisions may cause new problems, delaying real progress toward sustainability.
4
Describe consequences
Identify outcomes of failing to use life cycle thinking.
Identifying the Outcomes of Failing to Use Life Cycle Thinking
When life cycle thinking is ignored, environmental, economic, and social consequences often arise. Without a comprehensive, systems-level approach, decisions that appear beneficial in one area may cause unexpected problems elsewhere. The failure to consider the full life cycle of a product, process, or system can lead to resource depletion, pollution shifting, increased costs, and sustainability failures.
This section explores the key negative outcomes of neglecting life cycle thinking.
1. Pollution Shift: Solving One Problem While Creating Another
When life cycle thinking is not applied, efforts to reduce environmental impacts in one area may simply shift the problem elsewhere, leading to hidden trade-offs.
Example: Biofuels vs. Land Use Change
Biofuels were initially promoted as a sustainable alternative to fossil fuels due to their lower carbon emissions.
However, increased demand for biofuel crops led to deforestation and land use change, releasing large amounts of CO₂ from soil and forests.
In some cases, the total carbon footprint of biofuels exceeded that of traditional fossil fuels, negating their intended benefit.
Example: Electric Vehicles (EVs) and Battery Waste
EVs reduce tailpipe emissions, but their batteries require lithium, cobalt, and nickel mining, which can cause water pollution, habitat destruction, and human rights issues.
If not properly recycled, battery disposal becomes an environmental hazard, contributing to toxic waste.
Without life cycle planning, EV technology could solve urban air pollution while exacerbating mining-related environmental problems.
2. Increased Resource Depletion and Waste
Ignoring life cycle thinking often leads to unsustainable resource consumption and excessive waste generation.
Example: Single-Use Plastics
Plastic packaging is often cheaper and more efficient than alternatives like paper or glass.
However, without proper recycling infrastructure, single-use plastics accumulate in landfills and oceans, causing long-term pollution problems.
The push for biodegradable plastics was initially seen as a solution, but some materials still require industrial composting and do not degrade naturally in the environment.
Example: Fast Fashion and Textile Waste
Many clothing brands prioritize low-cost, mass production, leading to short product lifespans and increased textile waste.
Synthetic fabrics like polyester shed microplastics during washing, polluting oceans and entering the food chain.
The lack of a circular economy approach results in millions of tons of clothing waste each year.
3. Higher Long-Term Costs for Businesses and Society
Failure to integrate life cycle thinking often leads to higher costs in the long run, both for businesses and society.
Example: Poor Infrastructure Planning
Cities that prioritize short-term construction cost savings without considering energy efficiency and maintenance costs often end up with higher long-term operational expenses.
Buildings without sustainable designs require more energy for heating, cooling, and lighting, increasing both carbon emissions and financial costs.
Example: Over-Reliance on Fossil Fuels
Countries that fail to invest in renewable energy infrastructure early face higher energy costs and supply chain instability in the future.
Transitioning away from fossil fuels becomes more expensive the longer it is delayed.
4. Unintended Environmental and Social Consequences
When products and policies are not evaluated with a life cycle perspective, unexpected consequences may arise, affecting both the environment and human well-being.
Example: Compact Fluorescent Lamps (CFLs) vs. LED Bulbs
CFLs were once promoted as a more energy-efficient alternative to incandescent bulbs.
However, they contained mercury, creating hazardous waste disposal challenges.
LEDs eventually replaced CFLs as a superior, low-impact lighting solution, demonstrating the importance of anticipating long-term consequences.
Example: Globalization and Carbon Footprint
Outsourcing manufacturing to countries with cheaper labor can reduce business costs, but it often results in higher carbon emissions due to increased transportation and coal-powered energy use.
Many companies now incorporate carbon footprint assessments in their supply chains to address these hidden environmental costs.
5. Lost Opportunities for Circular Economy and Sustainability
Without life cycle thinking, industries miss opportunities to design waste out of the system and create circular economy models.
Example: Electronics Waste (E-Waste)
Many electronic devices are designed for obsolescence, making repairs difficult and increasing electronic waste.
Without policies like extended producer responsibility (EPR) and product take-back programs, companies miss the chance to recover valuable materials like copper, gold, and rare earth metals.
Example: Agricultural Supply Chains
Farms that focus only on yield maximization without considering soil health and biodiversity end up depleting their land, requiring more chemical fertilizers and harming ecosystem balance.
Sustainable farming techniques, like crop rotation and regenerative agriculture, offer long-term benefits, but they require life cycle planning.
Summary: The Risks of Ignoring Life Cycle Thinking
Without life cycle thinking, decision-makers risk creating short-term solutions that cause long-term damage. The key risks include:
✅Pollution shifting – solving one problem while creating another. ✅Increased resource depletion – failing to manage raw materials efficiently. ✅Higher long-term costs – making short-sighted economic decisions. ✅Unintended environmental and social consequences – ignoring systemic impacts. ✅Missed opportunities for circular economy – failing to close material loops.
By integrating life cycle thinking, businesses, policymakers, and consumers can avoid these risks, enhance sustainability, and make smarter environmental decisions for the future.
What is a Life Cycle?
Definition
A series of stages or changes in the life of an organism, product, or system.
Natural Examples
Butterfly metamorphosis, water cycle.
Manmade Examples
Aluminum can, cellphone, car.
Key Theme
Continuous, stepwise path with no clear breaks.
Life Cycle Stages
1
Cradle to Grave
Birth to death of a product.
2
Cradle to Gate
Birth to factory gate.
3
Cradle to Cradle
Complete recycling.
Examples: Fruit (Farm → Market → Consumption → Waste) and Tuxedo (Factory → Sale/Rental → Use → Disposal).
Why Life Cycle Thinking?
Complex Problems
Environmental issues are interconnected and multifaceted.
Avoiding Consequences
Decisions without life cycle thinking lead to unintended outcomes.
Real Examples
Electric vehicles (lead-acid batteries) and CFLs (mercury disposal).
Systems Thinking
1
1
Interconnected Parts
Life cycles are systems with linked components.
2
2
System Boundaries
Define what's included in the analysis.
3
3
Analysis Scope
Services, urban areas, and entire systems can be analyzed.
Environmental Impacts
Fossil Fuel Depletion
Use of non-renewable energy sources.
Global Warming
Greenhouse gas emissions (CO2, CH4, N2O).
Ozone Depletion
CFCs and other ozone-depleting substances.
Acid Rain
Sulfur dioxide (SO2) and nitrogen oxides (NOx).
Life Cycle Thinking in Action
Chapter Summary
Systems-Level View
Life cycle thinking provides a holistic perspective of products and processes.
Impact Identification
It helps identify environmental impacts across all stages of a product's life.
Informed Decisions
Without it, decisions may lead to unintended consequences.
End of Chapter Questions
1
Soft Drink Container
Describe the life cycle stages of a soft drink container.
2
Simple Product
Draw a life cycle diagram for a simple product.
3
Fossil Fuel Impacts
Explain the environmental impacts of fossil fuel power plants.
4
Laptop Life Cycle
Discuss the life cycle stages of a laptop computer.