Ökobilanz (LCA)

Is a refurbished notebook more environmentally friendly than a new one? How large is the share of manufacturing in the CO₂ footprint of a server? A life cycle assessment answers such questions. This entry explains how a life cycle assessment according to ISO 14040 and 14044 is structured, what it shows for IT hardware and where its limits lie.

The four phases of a life cycle assessment

Phase	What happens
1. Goal and scope	Defining what is examined and for what purpose. This includes the functional unit, for example "one notebook over five years of office use", and the system boundaries.
2. Life cycle inventory	Recording all material and energy flows: raw materials, energy, transport, emissions and waste.
3. Impact assessment	Translating the flows into environmental impacts, for example global warming potential, acidification, resource or water consumption.
4. Interpretation	Reviewing results, naming uncertainties and drawing conclusions.

Depending on the question, only part of the life cycle is considered. "Cradle to Gate" ends at the manufacturer's factory gate, "Cradle to Grave" includes use and disposal.

What life cycle assessments show about IT hardware

For notebooks, smartphones and tablets, a large share of the environmental impact comes from manufacturing, above all chips, circuit boards and displays. This effort is described by the term embodied energy. It follows that the longer a device is used, the better its footprint per year of use. Continued use as a refurbished device can replace the manufacture of a new device. How large the effect is in an individual case depends on the device, assumptions and data basis.

Many manufacturers publish a Product Carbon Footprint for their models. It is an excerpt of a life cycle assessment and considers only the climate impact; the methodology for it is described in ISO 14067. More on the climate perspective in the entry Carbon footprint of IT hardware.

Limits and typical misunderstandings

• Assumptions determine the result: Service life, electricity mix and recycling rate change the figures significantly.
• Data quality: Many values come from databases with average values, not from the specific factory.
• Comparisons need review: Anyone who publicly claims that one product is more environmentally friendly than another needs, under ISO 14044, a critical review by independent experts.
• Not a substitute for the corporate footprint: The greenhouse gas inventory of a company according to Scope 1, 2 and 3 follows its own rules. However, life cycle assessments provide important input data for it.

How to realistically assess the actual environmental impact of your IT is shown in the article How green is your IT really?

Life cycle assessment and Second IT

Second IT prioritizes reuse before recycling: decommissioned devices are certifiably erased, refurbished and remarketed. For your CSR and ESG reporting you receive recycling and disposal records as well as an annual, individual environmental report. Second IT is certified for environmental management under ISO 14001. More on sustainable recovery and disposal.

Frequently asked questions about life cycle assessment

What is the difference between a life cycle assessment and a CO₂ footprint?

The CO₂ footprint considers only the climate impact. A life cycle assessment additionally evaluates other environmental impacts such as resource consumption, acidification or water consumption. The footprint is thus a partial result of a life cycle assessment.

Which standards apply to life cycle assessments?

ISO 14040 describes the principles and framework, ISO 14044 the requirements and guidelines. For the CO₂ footprint of products there is additionally ISO 14067.

Is a refurbished notebook better in a life cycle assessment than a new one?

In many cases yes, because the manufacture of a new device is avoided and the effort for refurbishment is usually low. There is no blanket result, though. It depends on whether the refurbished device actually replaces a new one and how long it is used.

What do Cradle to Gate and Cradle to Grave mean?

These are system boundaries of a life cycle assessment. Cradle to Gate ends at the manufacturer's factory gate. Cradle to Grave includes use and disposal. Depending on the question, only part of the life cycle is considered.

What is the functional unit in a life cycle assessment?

It defines what all results refer to, for example "one notebook over five years of office use". Results can only be compared if the functional unit and system boundaries match.