Design for Environment (DfE), Eco Design, Green Engineering

Life Cycle Costing & Reverse Logistics

© Colin Fitzpatrick

Introduction

Design for X

Design is often mistakenly considered as merely providing the blueprint to satisfy functional specifications

Design practices must include a host of other desired attributes known as the design for concept

Examples include “design for assembly (DfA)” & “design for testability (DfT)”

DfX

Design for Assembly Design for Compliance Design for Disassembly Design for Environment Design for Logistics Design for Manufacturing Design for Orderability

Design for Product Retirement

Design for Quality Design for Recycling Design for Reliability Design for Safety Design for Serviceability Design for Testability

DfE

Efforts to incorporate environmentally friendly engineering practices are known as Design for Environment, Green Design or Eco Design

Design of a product has the highest influence throughout its lifecycle

Avoid “over the wall engineering” and move toward “concurrent design”

Life Cycle Thinking

Life Cycle Thinking

Life cycle thinking is at the heart of Eco Design Starts with resources taken from nature and

concludes with end of life stage. Sometimes called cradle to the grave approach

or cradle to reincarnation Legislators “encouraging” such an extended

producer responsibility approach

Life Cycle Thinking

Holistic view where design options should not have a reduced impact at one life cycle stage at the expense of increasing the impact on the complete life cycle

Only if the complete life cycle of a product is taken into account can an assessment of the environmental performance of a product be made

Life Cycle Thinking

Consideration of the entire life cycle can help ensure that

– No materials are arbitrarily excluded– All the environmental and economic characteristics of a

product are taken into account– Consideration is given to impacts generated by intermediate

products– Focus is not only on the environmental impact of the product

itself but also on the system in which it will perform– Environmental impacts are not merely shifted from one life

cycle phase to another or from one medium to another

Life Cycle Thinking

A life cycle approach should be able to define the best design strategy in order to reduce the environmental impact of a product. This can affect the life cycle stages of a product as follows

– Extraction of raw materials– Production of materials– Manufacturing of parts– Manufacturing of sub-assemblies– Assembly of the end product– Distribution– Use & Maintenance– End of Life Treatment

Life Cycle Thinking

Helps to avoid “displaced impacts” such as– A recycling process that consumes more energy, possibly in

transport as well as processing, than is saved by recovering material

– A miniaturised product, using fewer materials than its precursor, that is impossible to deal with at its end of life stage because of its complex design and use of mixed materials

– More energy embodied in the manufacture than can be saved in the use phase of an energy efficient product (not normally an issue in electronic goods!!)

– Products lifetimes over extended by being robust and consuming more materials. New technology could permit its replacement with enhanced energy efficiency

Raw Materials

What environmental impacts do the materials cause?

– Materials consist of resources and production of them needs energy.

– Some materials, e.g. copper produce a lot of waste during extraction, because the ores only consist of a small amount of copper.

– Material extraction needs a variety of chemicals and can lead to emissions of more or less toxic substances.

Raw Materials -Energy Consumption

– All materials need energy to be produced. This processing energy - needed for extraction, refining and further processing of virgin resources into 'ready-to-use' materials - will typically be electrical or thermal. Some materials like plastics are synthesised from energy sources like gas or oil and thereby have an inherent energy content. The total energy input to a material is the sum of processing and inherent energy.

– Some of the inherent energy in plastics may be recovered by incineration. This energy corresponds to the combustion value of the material. It should be remembered that this energy can not be recovered 100%, as it has to be corrected by the efficiency of the incineration system!

Raw Materials –Limited Resources

– No matter what we do, the amount of resources is limited. Use of fossil fuels is an irreversible process - once they have been used, they have gone. For metals, the resources do not disappear, but if we don't take care of them, we end up diluting them to such an extent in the waste streams that re-extraction of them will be very energy intensive

– A way of describing the scarcity of resources is by defining the "World Reserves Life Index" (WRLI). It is based on the amount of reserves (the amount of a resource that is economically profitable to extract) and the consumption of resources. WRLI is defined as the reserve divided by the yearly consumption of the resource. It gives the number of years we have left of a given resource, assuming constant reserves and constant consumption.

Reduce the environmental impacts

Avoid hazardous materials Avoid mixing of materials.

– For the recycling industry, there can be different reasons to disassemble the equipment: The equipment may contain substances or components that according to legislation must be removed and treated separately.

– The scrap value is higher, when more pure material fractions can be recovered by dismantling and separation. The labour costs for this dismantling and separation process must of course be lower than the gained increased in scrap value.

General checklists for materials

Recommendations concerning materials in general

Reason for recommendation

Use as few different types of

materials as possible Makes it easier to sort materials for recyclingLarger amounts of similar materials increase the value of the scrap

Avoid use of dangerous and hazardous substances

Reduce the risk of contact with hazardous substances during manufacturing, use and disposal Reduced costs for disposal

Avoid using materials characterized

as scarce resources Limits the use of scarce resources

General checklists for materials

Recommendations concerning materials in general

Reason for recommendation

Use materials which can be recycled in the established recycling systems

Reduces consumption of resources and means higher value on disposal

Reduce consumption of materials, avoid over-dimensioning

Reduces consumption of resources and means higher value on disposal

Reduce spillage and waste Reduce consumption of resources

Reduce packagingLabel materialsTake care that different materials can be separated

Reduces consumption of resourcesStimulate recycling

General checklists for materials

Materials, plastics Reason for recommendation

Use as few different types of plastics as possible

Makes it easier to sort materials for recyclingLarger amounts of similar materials increase the value of the scrap

Choose plastics, which: can be recycled, i.e. thermoplastics (e.g. PET, PS) and polyolefines (e.g. HDPE, LDPE and PP)are compatible on recycling

Increases possibility of recycling

General checklists for materials

Materials, plastics Reason for recommendation

Choose plastics which can be incinerated without emission of hazardous substancesAvoid PVC and other halogen containing polymers

Since incineration of plastics is the most realistic disposal routeIn case of fire in electric and electronic equipment, PVC will emit chlorine, and the hydrochloric acid which is formed can result in considerable damage of the installations and other equipment

Avoid brominated flame retardants Toxic substances are emitted during incineration at low temperature. Some of the flame retardants are toxic themselves (PBB, PBDE)

General checklists for materials

Materials, plastics Reason for recommendation

Plastic parts which are joined together should be made of the same materials

Eases recycling

Avoid glued labels on the plastic surface

Contaminates material on recycling

Manufacture

The sources of environmental impacts from the production or manufacturing stage are consumption of energy, water and ancillary substances. Waste and emissions are typical outputs.

Use Phase

The main contributors to the environmental impact during the use stage are:

– Energy consumption– Maintenance and cleaning– The lifetime of the product also influences the impact.

Use Phase

Electrical and electronic products are characterised by energy consumption in the use stage. For many products the energy consumption is by far the most important contributor to the environmental impact, but it is not necessarily so. However, if little is known about the products and its environmental performance, energy reduction is a good start.

Maintenance is connected to lifetime. The better the maintenance, the longer the lifetime, and generally, the smaller the environmental impact. Maintenance includes repairing, changing parts, lubrication etc. Cleaning must not be forgotten. Cleaning can include cleaning agents with high environmental impacts.

Use Phase

The lifetime of a product influences the use of materials (which will be divided over the lifetime in years), but usually it has no influence on the energy consumption per year. Please observe, however, that energy consumption of newer products is often lower due to improved efficiency.

For electronic equipment, several studies have shown that the energy consumption during stand-by is considerable. Older equipment used to have an on/off-switch, which would completely disconnect the equipment from the mains. Newer equipment stores information, is often remote controlled, and must be able to react immediately on external events. This makes it mandatory, that the power supply is active all the time, and consequently the efficiency of this is extremely important.

Use Phase

Recommendations concerning reduction of energy consumption and other consumptions

Reason for recommendation

Use automatic power-down and standbyMake sure that the energy consumption is minimal in these situations, because the existence of automatic power-down/standby means that the equipment will not be turned off when not in use

Most equipment is turned on all the time, but it is only active part time (TV, VCR, Set-top boxes, Audio etc.)It is a typical demand in environmental labelling

Minimise the energy consumption during use, e.g. by:High efficiency in power supplyAs low clock-frequencies as possibleReducing the supply voltage as much as possibleHigh degree of integration normally reduces consumption

Reduces environmental impactSaves money for the customer (competitive advantage)

R. Broderson ,ISSCC 2003

R. Broderson ,ISSCC 2003

End of Life

When a product is send to landfill not only are the precious components and materials wasted but also toxic substances in the product can leak out and contaminate underground water and soil

Need to consider Design for Product Retirement in the design stage

Options include Reuse, Upgrading, Re-Manufacturing, Recycling

Life Cycle Costing

Life Cycle Costing

Incorporation of “green features” seen as desirable Often perceived as too expensive Need to account properly for the long term costs and benefits

of their products Environmental progress is sub optimised by imperfect analysis

leading to unclaimed opportunities for enhanced profitability Changing nature of production aswell as regulatory

parameters have challenged the old conservative bean counter system to get the maths right

If companies could improve at tracking costs they can design better for the long run and find it more profitable

What gets Measured gets Managed

Life Cycle Costing

Electronic products often have very short life cycles Leaves little time for exploring cost-capturing tools

such as life cycle costing “Urgent Vrs Important” urgent usually wins Rather than disappear from the balance sheets at the

point of sale many products will now be returned Current accounting and financial models disregard the

serious cost ramifications of policy and preference shifts

Life Cycle Costing

DfE can fail to incorporate common business considerations

Limits its acceptance and influence To sell a concept internally it is best to use

terms and ideas that managers understand All understand accounting and cost-reduction

Life Cycle Costing

Life Cycle Costing is an accounting model which must be considered as early as possible in the design stage

Important in understanding and maximising product value not just through one product incarnation but through many

Life Cycle Costing

Establishing costs of a product over its entire existence

In addition to research & development things like product design, storage, inspection & maintenance, administrative, program management, disposal, insurance, potential clean-up, potential liability costs related to an environmental impact should be included in a projects total cost assessment

Life Cycle Costing

Firm realises product benefits of its product only once

A B C

A B C

€100 €100 €100Cost

€200 €200 €200Price

Today Totals

€300

€600

Total Profits €300

Life Cycle Costing

Contrast this with scenario B– Designed in longevity– Tracking the costs over more than one use– New Manufacturing cost increased by 10%

Better materials Design improvements Provides the product with worth on its return

– After take back and reconditioning it will have a 2nd or 3rd revenue potential when it is resold or leased

Life Cycle Costing

A B C

A B C

€110 €110 €110Cost

€200 €200 €200Price

Today Totals

€330

€600

Total Profits €270

Life Cycle Costing

A B C

A B C

€40 €40 €40RefurbCost

€130 €130 €130Price

Two Years from Today Totals

€120

€390

Total Profits €270

Life Cycle Costing

First incarnation sales show a slightly decreased profit

Not necessarily the case that environmental upgrades or LCC will give a higher price product and often the opposite is true

Good to envision the conservative scenario Profits from a single life cycle $300 Combined first and second sales profits $540

Life Cycle Costing

Assumed refurbishing costs including storage and retrieval $40

Must account for the time value of money Important to look at a range of possibilities, sensitivity

analysis Wont be able to predict all future costs with exact

certainty Will gain more insight than it no costs were tracked

throughout the life cycle of a given product

Life Cycle Costing

Example– Camera company responding to European Legislation on

packaging reduction fortified the actual camera– Accommodated less protective packaging but also

Less warranty repairs Compliance Reduced packaging cost

– Only for life cycle costing may have erroneously believed that the extra material required was not worth the cost

Life Cycle Costing

Vision of value in end of life Reclaimed EoL products = ingredients Margins on the used products are often higher Larger inventory of parts means better able to

service contract maintenance customers Previous accounting practices led to believe

this would not be profitable Xerox example

Reverse Logistics

Definition of Logistics – Logistics is defined as a business planning

framework for the management of material, service, information and capital flows. It includes the increasingly complex information, communication and control systems required in today's business environment

Reverse Logistics

Definition of Reverse Logistics– The supply chain that flows opposite to the traditional process

of order acceptance and fulfilment. For example, reverse logistics includes the handling of customer returns, the disposal of excess inventory and the return journey of empty trucks and freight cars.

– A specialized segment of logistics focusing on the movement and management of products and resources after the sale and after delivery to the customer

Reverse Logistics

Most expensive part of take back Take back needs economies of scale More difficult to design an economically viable

EoL solution than simply to be ecologically viable

Refurbishment, re-use & recycling will live or die by reverse logistics

Reverse Logistics

Need to examine– Collection area, population density– Spectrum of products being delivered– Product life cycle times– Recycling potential– Recycling infrastructure– Costs

Collection, transport, handling, storing, sorting, disassembly + REVENUES

– Suitable Equipment for recovery

Further Reading

Lewis Ch9 Design + EnvironmentCh5 & Ch18,19 Goldbergwww.ecodesignguide.dk