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Appendix E: Peer Review Panel Comments and Responses

Critical Review Panel

Life Cycle Assessment of Product Stewardship Options for
Mercury-Containing Lamps In New Zealand

Review Statement on Draft Final Report

Members of Review Panel:   
Dr Sarah McLaren (Chair)   Landcare Research
Dr Barbara Nebel                  Scion
Dr Donald Hannah                ERMA

Date of meetings:
Thursday 28th May 2009, 3.00 pm to 4.15 pm
Tuesday 2nd June 2009, 9.00 am to 10.30 am
Friday 5th June 2009, 11.30 am to 12.40 pm

Summary

The Ministry for the Environment has contracted ERM to undertaken an LCA study of mercury-containing lamps – in the context of development of a product stewardship scheme for these products in New Zealand. A Critical Review Panel for the study was set up by the Ministry for the Environment consisting of Dr Donald Hannah (ERMA), Dr Sarah McLaren (Landcare Research) and Dr Barbara Nebel (Scion). Dr Sarah McLaren was appointed Chair of the Panel.

This document provides a summary of the Critical Review Panel’s assessment of the draft Final Report provided by ERM in May 2009. It is divided into: General Comments, Main Comments (for each section of the report), Minor Comments, and Reporting.

General Comments

Modelling use of mercury

Our understanding is that there is very little mercury now sourced from primary mining and that the mercury used in the fabrication of energy efficient lighting products is almost completely sourced from recycled mercury (either from recovery processes or from mercury from phased-out industrial processes).  The UNEP Global Mercury Programme (http://www.chem.unep.ch/mercury/default.htm) is a good source and starting point for following this up.  We think that, if this is taken into account, the conclusions of the report with respect to mercury are likely to be significantly different.  ERM response (1): The study has been updated to reflect recycled and recovered sources of mercury in lamp production.  This has been updated based on recently published and available data.  Based on the predominant countries of lamp manufacture: mercury used in China is predominantly from primary sources; mercury used in Thailand relates to both primary and recycled sources; while in the EU, mercury is primarily from recycled sources.  Further specific references and updates to the LCI/LCIA results are presented in the final report.  In terms of effect on final results, the above changes do not affect the main focus and overall conclusions of the report in any material way.  Overall, results in relation to the emissions and impacts of mercury have altered as follows:

  • LCI flows and LCIA results remain almost unchanged for whole life results and end-of-life only results.  Emissions of mercury to air and to land are dominated by the end-of-life stage.  Emissions to water are dominated by end-of-life and the manufacturing stage (for manufacturing this is from other (i.e. non-mercury) material production and electricity generation). 
  • For whole-life human toxicity impacts mercury contribution reduces by around 10%; although, total mercury contribution still remains below 0.5% for whole life.  For end-of-life only human toxicity impacts, mercury contribution to water and soil remain unchanged, but for emissions to water, these reduce by around 50%.  This reduction is due to the changes in offset benefits of the above modifications.  Nevertheless, the same overall conclusions are drawn from the results. 

In general, it was difficult to check modelling calculations because insufficient data have been supplied in the report.   ERM response (2): See responses below from ERM on specific areas where additional data have been requested.

We recommend that further details are provided throughout the text on quantities of mercury emissions released to different media.  ERM response (3): Additional resolution of data has been added in where LCI results are presented in Section 4 of the main report and Appendix C.

Modelling use of recycled aluminium, nickel and brass

Following on from the comment about use of recycled mercury above, we consider that further details should be provided about the modelling assumptions for avoided use of aluminium, nickel and brass. This is particularly in view of the fact that modelling of these metals appears to make a big contribution to the toxicity impact category results (as stated in Sections 5.4.2 and 6.4).  ERM response (4): Additional descriptive text has been added for these inventories as presented in Appendix B, Section B.10

Main Comments: Goal

Section 2.1

As per our comments in the earlier Review of the Goal and Scope Document, we consider that Section 2.1 should provide a fuller explanation of why there is a particular focus in the study on end-of-life management and mercury use in lamps.  ERM response (5): The original scope of work as defined by the Ministry for the Environment in New Zealand was to focus only on these aspects.  Additional descriptive text has been added in Section 2.1 to this effect.

The different scenarios are listed in Section 2.1. We suggest that these are numbered as Baseline Scenarios 1 to 6, and that there is consistency in using these scenarios throughout the document. In the current report, a Baseline Scenario with 9% recovery and recycling appears in the Impact Assessment results, and it is not clear how this relates to the list of scenarios in Section 2.1.  ERM response (6): Scenarios have been labelled as suggested, in order to ease interpretation and clarity of the results.

Also, for scenarios 4 to 6, what is the technically feasible minimum?  ERM response (7): The technically feasible minimum has been estimated based on a 10% reduction in mercury content.  This was estimated as the maximum mercury reduction that the manufacturers, which we were in contact with, felt could be achieved without significant changes in lamp design and unacceptable loss in performance.    Appendix B, Section B.11 presents the lamp mercury levels assessed in the study.  No additions or amendments to the report have been made.  

Section 3.3.2

As indicated in our earlier comments on the Goal and Scope Definition, the packaging and fittings/gear are not the same across the different lamp types, and so the sentences in Section 3.3.2 (p.18 and p.20) stating that the packaging and fitting gear are identical for the different lamp types is incorrect.  ERM response (8): The peer review panel has not read the text correctly as shown in the final report and this has been misinterpreted, as follows:

  • the sentence on page 18 which states “The following exclusions are made due to these being the same for each typical lamp type”. 
  • the sentence on page 18 which states “This is excluded because these components are identical within each lamp type”.

This does not state “across” lamp types, but “within” each lamp type – meaning that “within” each of the six lamp types assessed the packaging and fittings/gear are identical. 
In order to provide additional clarity, and as described in Section 2.1 of the LCA report, the goal of the study was to “…to assess the potential life cycle environmental impacts associated with the production, use and end-of-life management options for individual types of mercury-containing lamps in New Zealand.  […]  The study does not to provide comparative results across the different lamp types.  This is because the lamps offer a different function and performance characteristics relating to lamp lifetime, lamp output (in terms of wattage) and in terms of lamp application (although application may be the same in many cases for CFLe and CFLi lamps).  As such the lamps are not functionally the same and should not be directly compared.

Consequently, for the intended goal of the study, the “packaging and fittings/gear” are identical within each of the six typical lamp types assessed.  The study therefore excludes these from the assessment when making a comparison “within” each lamp type.  The comparison is made within each lamp type according to changes in recycling/recovery rates at end-of-life, alternate life times, alternate operating efficiency and alternate mercury levels in the product. 

Also, we note that the current version includes the packaging, product fittings and control gear at sensitivity analysis, and so this section needs to be updated to reflect the current study.  ERM response (9): The final report reflects the inclusion of a sensitivity analysis that addresses packaging and product fittings.

As an aside, we note from Figure 13 that the inclusion of packaging and fittings actually makes a 25% difference to the Freshwater Aquatic Ecotoxicity result (and a 15% difference to the Human Toxicity and Marine Aquatic Ecotoxicity results) for the compact fluorescent lamps with integral ballast. Therefore it is important to be take account of these ancillary items from a whole-of-life-cycle perspective.  ERM response (10): Refer to comment 8 above for their exclusion from the study.

Main Comments: Inventory Analysis

Data in Inventory Analysis (Section 3.7)

In general, it was difficult to check calculations because no data are supplied in this section. We feel the study would be more transparent if data on actual use of materials and energy are provided in this section. For example, Table 4 provides details on lamp composition; this could be moved to Section 3.7, and augmented with information on the specific datasets used for each of the materials.  ERM response (11): All data are provided Appendix B of the report which clearly and logically identifies all assumptions and data sources.  Please refer to Appendix B of the main report for these details.  No additions or amendments to the report have been made.

More details are also required in this section on actual energy use for each lamp type and other data assumptions and datasets used for each scenario. A clearer description of each life cycle stage with associated assumptions and data would provide further clarity in this section.  ERM response (12): All data are provided Appendix B of the report which clearly and logically identifies all assumptions and data sources.  Please refer to Appendix B of the main report for these details.  No additions or amendments to the report have been made.

Main Comments: Impact Assessment and Interpretation

Impacts of end-of-life

Informing end-of-life management options is stated specifically in the goal of the study. In this context it is valid to look at the end-of-life stage of the life cycle separately. However, the results need to be presented in a way that reflects the relative importance of this life cycle stage.

In order to allow an interpretation of the reported results, their relative importance should be stated. How significant is, for example, a saving of 0.8 kg of CO2 equivalents? (Last paragraph in Section 5.2).  ERM response (13): All results are presented initially as the entire life cycle which provides context for the end-of-life phase.  Where numerical results have been presented in the interpretation for the end-of-life phase, these have also been shown as percentage in terms of whole-life, as the example suggested by the review panel in Section 5.2.

Impacts of reduced mercury in lamps

Based on our understanding that mercury used in the fabrication of energy efficient lighting products is almost completely sourced from recycled mercury (see General Comments above), the results for terrestrial ecotoxicity will change.  ERM response (14): Refer to comment 1 from ERM for additions and amendments to the LCA study and effect on results that have been made.  No additional amendments made to the LCA report. 
Results using different Impact Assessment methodologies

The choice of Impact 2002+ and TRACI are in general regarded as appropriate by the Review Panel. However, it is stated that health impacts related to mercury are excluded in the TRACI methodology. It would be good to state if impacts related to mercury are included elsewhere in this methodology ERM response (15): The LCA report in Section 5.4 has been updated.

For the interpretation and transparency of the study, we recommend to include the results of the alternative Impact Assessments, i.e. to provide data related to the statements made in the last paragraph on p.61.
ERM response (16): The LCA report has been updated to provide some additional results tables of these two methods.

Section 5.4.2: End-of-life results

It is stated in Section 5.4.2 that nickel, brass and aluminium play an important role. We recommend quantifying the results for those metals in order to increase the transparency of the study.  ERM response (17): The LCA report has been updated with some additional LCIA results tables of these materials, which includes material extraction, production and transportation to point of manufacture.

Brass is not mentioned in Appendix B.10.  ERM response (18): Brass has been added to Appendix B.10.

Main Comments: Interpretation

Impacts of lamp warm-up and impacts of improved energy efficiency in the use phase

This scenario requires more detail with regard to the ‘warm-up’ effect. Quantifying the increased energy use as well as the increase in environmental impacts would help to clarify the second paragraph.  ERM response (19): An additional Table has been added to Appendix B.11 to show the changes in energy consumption from warm-up effects.  The Figure shown in Section 6.2 provides results which quantify the changes that result from warm-up effect sin relation to the baseline scenario.

Does the “0.5% scenario” in Figure 10 relate to the warm up effect? This needs clarification.  ERM response (20): The 0.5% scenario relates to the scenario for warm-up effects.  The 0.5% represents the percentage difference in energy usage compared to baseline, as described in Appendix B.11.  The Figure in Section 6.2 of the LCA report has been updated to identify this scenario more clearly. 

The title of this scenario also does not correspond with the scenarios listed on page 67.  ERM response (21): The Figure in Section 6.2 of the LCA report has been updated to reflect same names as shown on page 67.

Section 6.3: Impacts of open- and closed-loop recycling

The terms ‘open-loop’ and ‘closed-loop’ recycling requires a short explanation.
The second sentence in the third paragraph needs clarification.  ERM response (22): Additional text to clarify has been added to Section 6.3 of the LCA report.

Section 6.4

The text in Section 6.4 does not correspond with the related Figures in all aspects. The second Figure 12 (see also minor comment related to p.75/76) shows environmental benefits for fresh and marine ecotoxicity - the words ‘and fresh and marine water’ therefore need to be deleted in the third paragraph.  ERM response (23): Agreed.  Interpretation of results should only relate to terrestrial ecotoxicity.  Text shown in Section 6.4 has been amended.

The last paragraph is also not in line with the second Figure 12. The text states that increased levels of recycling improve the environmental performance. This is also what would be expected due to reduced emissions from the disposal stage. The second Figure 12, however, shows opposite results except for terrestrial ecotoxicity.  ERM response (24): Agreed.  Interpretation of results should have stated ‘decreased’ rather than ‘increased’ in the first sentence of last paragraph.  The second sentence of the last paragraph has been updated to reflect the results correctly.

Section 6.5: Potential impacts of packaging and fittings

Providing separate results for packaging and fittings would increase the transparency of the results. Also this section states that packaging has a negligible effect, it would be good to provide the data for this.  ERM response (25): The LCA report has been updated in the appendix  to provide some additional LCIA results tables of the packaging  materials, which includes material extraction, production and transportation to point of manufacture.

Figure 13 shows an approximate increase for fresh water ecotoxicity of 25%. As noted earlier in this Review, this seems to be a significant change and should be reflected in the text.  ERM response (26): The text has been updated to reflect the scale of changes in the results compared to the baseline. 

Main Comments: Conclusions

Mercury contribution

The first sentence of Section 7.2.1 needs some clarification. We realise that this section is within the section on ‘End-of-Life Conclusions’, but the reference to ‘total impacts’ in section 7.2.1 is slightly misleading. We recommend changing it to “end-of-life” impacts.  ERM response (27): The LCA report text has been updated in Section 7.2.1 to reflect recommendation.

Minor Comments

p.19 In Figure 1 it would be clearer to draw a labelled system boundary around the system under analysis i.e. it includes the “energy supply systems” and “other product systems” but excludes the “environment” categories at the top and bottom of the diagram.  ERM response (28): The LCA report has been updated to reflect recommendation.

p.21 Section 3.4.1 first sentence, provide a reference to justify the source for stating that system expansion “should” be applied.  .  ERM response (29): The LCA report has been updated to reflect this comment.

p.22 The reference for the equation under Figure 2 should be stated.  ERM response (30): The LCA report has been updated to reflect recommendation.

p. 23 Why does the second paragraph refer to ‘provisional’ results?  .  ERM response (31): Incorrect text shown in the LCA report.  The LCA report has been updated to reflect this comment.

p.24 We do not understand the sentence in the second paragraph, “an estimate is used for geothermal electricity generation based on hydro generation.”  ERM response (32): The LCA report has been updated to provide further clarification.  Appendix B provides specific details and assumptions used. 

p.24 Regarding the “Lamp energy consumption” paragraph, we note that the sensitivity analysis in Section 6.2 (p.70) considers a situation where there is both increased power required in the initial period of operation AND a 10% improvement in energy efficiency over the lifetime of the lamps. Is there a direct correlation between these two aspects? If not, why have the two been considered together at sensitivity analysis?  ERM response (33): There is no direct correlation between these two sensitivities.  Nor have the results been aggregated in any way as presented in Section 6.2.  The results are simply shown in the same section and the same results figure in order to provide a useful comparison on the same results Figure to indicate scale of difference between these changes associated with baseline versus a 10% improvement in energy efficiency and lamp warm-up effects.  No changes or updates made to the LCA report. 

p.27 Section 3.6.3 The International Journal of LCA is not a database  ERM response (34): The LCA report has been updated to reflect this comment.

p.29 Table 6 does not include PAH and NMVOC yet these groups of substances make the biggest contribution to Human Toxicity (Section 5.4.1). We are not sure of the overall value of Table 6.  ERM response (35): The LCA report has been updated to reflect this recommendation.  The Table has been deleted from the report.

p.31 Section 3.9 mentions “provisional results” but presumably these should be final results.  ERM response (36): Incorrect text shown in the LCA report.  The LCA report has been updated to reflect this comment.
p. 38 Add ‘abiotic’ in first bullet point (depletion of abiotic resources) ERM response (37): The LCA report has been updated to reflect this comment.

p. 46 Table 10 – change unit for Eutrophication potential to PO4-3   ERM response (38): The LCA report has been updated to reflect this comment.

p. 47 Figure 9 – Abbreviations are only provided for GWP and ODP not for other impact categories. ERM response (39): No update made to LCA report.  

Add ‘)’ after ODP abbreviation.  ERM response (40): No changes have been made to the report.  This minor formatting issue hasn’t been easy to resolve with the LCA software used. 

p. 55 Numbering of Figures from here to the end of the report needs to be checked. Figure on page 55 is Figure 3 – there was already a Figure 3 on page 40.  ERM response (41): The LCA report has been updated to reflect this comment.

p. 62 It is not obvious from the caption for Table 13 that is relates to the base scenario. This should be stated in the caption.  ERM response (42): The LCA report has been updated to reflect this comment.

p. 64 4th paragraph – 2nd sentence. This sentence needs clarification. We assume that it should be ‘of mercury production’ instead of ‘of mercury emissions’.  ERM response (43): Correct assumption.  The LCA report has been updated to reflect this comment.

p. 67 First paragraph – change ‘reduce’ to ‘reduced’

second paragraph line 2 – change ‘sue’ to ‘due’

third paragraph – provide a reference for ‘research indicates’

ERM response (44): The LCA report has been updated to reflect these comments.

p.68 Last paragraph, reference research that indicates increased life requires increased mercury levels  ERM response (45): The LCA report has been updated to reflect these comments.

p. 75/76 Numbering of figures - both figures are ‘Figure 12’ ERM response (46): The LCA report has been updated to reflect these comments.

Reporting

The requirements for reporting are specified in detail in Section 5 of ISO 14044. The Review Panel has reviewed this report for consistency with those guidelines and concludes that the report in general complies with those requirements once the comments from the Review Panel are addressed.  ERM response (47): All peer reviewer comments have been addressed above.

The requirements of the Inventory Analysis specifically require a qualitative and quantitative description of the unit processes. Although the Review Panel acknowledges that the data are provided in the appendix, we suggest that key data for unit processes are presented in the main text.   ERM response (48): All data is provided in the Appendix in order to maintain ease of reading the final LCA report.  Reference to Appendix B should be made for further details. 

ERM response (49): ERM would like to thank and acknowledge the peer review panel members for their thorough, concise and helpful comments supplied in their review of this ISO LCA study.

Dr Sarah McLaren
Dr Barbara Nebel
Dr Donald Hannah
15 June 2009