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8 Conclusions

The analysis suggests that there is the potential to increase rates of recycling at a positive net benefit for nearly all waste streams. The only exceptions to this are PVC, LDPE and organics for which, under low benefit estimates, the results suggest that recycling rates are currently higher than optimal. For organics, it should be noted that the analysis of costs assumes a different collection methodology from that used currently. Specifically, the analysis assumes that kerbside collection of organic material is used rather than the current drop-off system. Therefore the results cannot be used to conclude that current rates of recycling of organics are too high, but rather that switching to the different collection method is justified only under the high benefit value assumptions.

Clear glass shows net benefits of collecting close to current rates, although the estimates of current rates ignore the fact that considerable quantities are being stockpiled awaiting the identification of suitable markets. The analysis here suggests it is worthwhile collecting some of this material for low (zero) value markets.

The contributing factors to the net benefits vary by material, but where they are included (household waste, including organics, end-of-life tyres and used oil), direct consumer benefits, estimated from a willingness to pay study undertaken in parallel with this study, are the most significant contributing factor to total benefits. These are potentially the most contentious elements of the analysis partly because, to our knowledge, such estimates have not been included in other recycling cost benefit analyses. However, the legitimacy of this benefit seems clear.

Willingness to pay studies can over-estimate benefits because people can over-state their willingness to pay when they do not believe that they will actually have to pay or they do not fully understand the payment mechanism. This is tackled to some extent through the inclusion of questions about willingness to spend time in addition to willingness to pay financially. However, there remains a degree of uncertainty regarding the size of these benefit estimates. This is so also because there is uncertainty over whether the respondents assumed that their willingness to spend time related to the current quantity of material collected or to an increased volume, for which there would be a requirement for additional time to be spent. The range of values used takes account of this uncertainty and the values are still sufficiently high to provide significant additional benefits of recycling. There would be value in further research into the willingness to pay values to better understand the assumptions being made by households.

Taking the full set of benefits into account, the results suggest that increasing rates of recycling in New Zealand is justified across all assumptions, for the majority of materials examined. Consistent with this, least cost instruments to achieve higher rates of recycling should be examined.

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