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Streamlined LCA. Streamlining the LCA Process. Full LCA is only practical with no limitations to time, expense, data availability etc… In practice consists of many compromises
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Streamlining the LCA Process • Full LCA is only practical with no limitations to time, expense, data availability etc… • In practice consists of many compromises • Although very extensive LCA’s have been conducted a complete quantitative LCA has never been accomplished nor is it ever likely to be • Design stage is best time to do LCA but very little data available at this point
Fully Comprehensive LCA Currently Accessible Region Extensive LCA Streamlined LCA LCA Scoping The LCA Continuum Ecoscreening
Streamlining the LCA Process • Screen the product with an inviolates list • Limit of eliminate life-cycle stages • Include only selected environmental impacts • Include only selected inventory parameters • Limit consideration to major constituents • Limit or eliminate impact analysis • Use surrogate data • Use qualitative rather than quantitative data • Eliminate interpretations or recommendations
The SLCA Matrix • Number of approaches developed adopting a matrix approach in which several life stages are evaluated for their potential impacts on a number of environmentally related concerns • Any SLCA process should allow for • Direct comparisons between rated products • Useable and consistent across different assessment teams • Encompass all stages of product life cycle • Address all relevant environmental concerns • Simple enough to permit relatively quick and inexpensive assessments
The SLCA Matrix Developed at AT&T
The SLCA Matrix • Values may be • Binary • 1 = problem • 0 = no problem • Ordinal • 1-10 severity ranking • 1-4 severity ranking • Assessor is providing a figure of merit to represent the estimated result from a more formal LCA • Should be guided by experience, design & manufacturing survey, appropriate checklists & other available info
The SLCA Matrix • Once an evaluation has been made for each matrix element the overall Environmentally Responsible Product Rating (RERP) is computed as the sum of the matrix element values • Process is qualitative and utilitarian but does provide a numerical end point against which to measure improvement
The SLCA Matrix • Assignment of integer ratings may seem subjective, experiments at AT&T have been performed in which comparative assessments of products are made by several different industrial and environmental engineers. Overall product ratings differ by no more that 15%
SLCA Assets • More efficient & less costly (days vrs months) • Useable at the early stage of design when opportunities for change are greater • Evaluate design attributes which are inherently qualitative such as ease of dissassembly
SLCA Liabilities • Little or no ability to track overall material flows • Little ability to compare completely dissimilar approaches to fulfilling a need • Little ability to track improvements over time
Cumulative Energy Demand as SLCA Ref:Mhuijbregtsm M, Hellweg S, Hensriks "Cumulative Energy Demand As Predictor for the Environmental Burden of Commodity Production" Environ. Sci. Technol., Article ASAP DOI: 10.1021/es902870s
CED as SLCA CED time
Estimating the materials and manufacturing energy of your product • 1. Define your bill of materials • 2. For the “energy cost of common materials” table to estimate the energy cost of the materials production. This from Vaclav Smil “Energy in Nature and Society, General Energetics of Complex Systems” • . • 3. Use table 1 from Ciceri et al to estimate the manufacturing energy cost of these common materials
Estimating the materials and manufacturing energy of your product • . • 3. Use table 1 from Ciceri et al to estimate the manufacturing energy cost of these common materials
Estimating the materials and manufacturing energy of your product
Estimating the materials and manufacturing energy of your product • 4. Identify what electronics are going to be part of your product, how is the function to be delivered. Estimate the size of the PCB required and how many layers. Use Table 3 from Ciceri et al to identify the energy cost of the PCB. Use the same table to estimate the energy cost of the chips. • 5. Identify the display technology to be used and the size. Again use table 3 to estimate the energy required.
Estimating the materials and manufacturing energy of your product
Estimate the energy consumption of your product • 1) What is the energy consumption in use mode? • 2) What is the energy consumption in other modes (sleep, hibernate, etc…)? • 3) How does it spend in each state? • 4) How many years will it be in service for? • If your product is “SMART” it should also know about what is happening on the electric grid. You can find the most important information from the following websites • 1) http://www.eirgrid.com (CO2 intensity & wind generation) • 2) http://www.sem-o.com (predicted wholesale electricity price, predicted system demand)