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National Wood Burner Performance Review: Phase 1

Executive Summary

1 Introduction

2 Methodology

3 Design Verification

4 Conclusions

Appendix 1: Wood Burner Lists for Testing

Appendix 2: Protocol

1 Introduction

1.1 The national environmental standards

The Resource Management (National Environmental Standards Relating to Certain Air Pollutants, Dioxins and Other Toxics) Regulations 2004 were promulgated on 6 September 2004. For the purposes of this report, these regulations will hereafter be referred to as either “the regulations” or “the NES”.

The regulations require that from 1 September 2005 all new wood burners installed on properties less than two hectares must have a maximum particle emission of 1.5g/kg and a minimum efficiency of 65% when tested in accordance with AS/NZS 4012/4013. Under the Resource Management Act 1991 responsibility for enforcing the regulations is devolved to regional councils and unitary authorities.

Under the regulations, a wood burner is defined as:

(a) a domestic heating appliance that burns wood; but

(b) does not include -

i. an open fire; or

ii. a multifuel heater, a pellet heater, or a coal burning heater; or

iii. a stove that is -

(A) designed and used for cooking; and

(B) heated by burning wood.

As noted, the regulations do not apply to burners installed in properties over two hectares. This means that it is not illegal to manufacture or sell non-compliant burners in New Zealand. It is however, illegal to sell or advertise that a wood burner meets the regulations if it does not.¹

Two key drivers behind the introduction of the NES were to:

• reduce emissions to air – the emissions and efficiency limits are important tools for improving air quality and public health in urban New Zealand

• provide a level playing field for industry – setting a design standard for wood burners provides for competition in a fair environment.

1.2 Design verification testing

In April 2006 the Ministry for the Environment (the Ministry) announced the commencement of a review of wood burners under the NES. The aim of the review was to provide consumers, retailers and installers with confidence that the products they are purchasing and installing are compliant with the regulations.

In designing the review, the Ministry was mindful of the regulatory history of wood burners in both New Zealand and Australia. The regulations introduced in 2005 build on a voluntary emissions limit of 4.0g/kg that was adopted in a joint New Zealand and Australian standard in 1999.² This emission limit has since been adopted as a mandatory standard in most states and territories of Australia. In 2003 the Department of Environment and Heritage (Federal Government of Australia) commissioned an audit of wood burners involving:³

• emissions and efficiency testing of 12 wood burners

• design verification testing of a further 35 models.

Design verification testing is a physical inspection of a burner for comparison with its original design as described in the emissions and efficiency test report. This test is much quicker and cheaper than a full emissions and efficiency test, which typically requires around four days test work in the laboratory.

Results from the Australian audit showed the extent of non-compliance was significant. An analysis of burners tested for emissions performance found the presence of engineering design faults was a good indicator of emissions non-compliance. These results provide confidence that the design verification test is a good indicator of whether or not a burner will comply with its stated emissions and efficiency.

1.3 New Zealand regulatory context

In New Zealand, wood burners are authorised for installation by either Environment Canterbury or Nelson City Council in accordance with the rules in their respective regional plans.⁴

Environment Canterbury requires burners have a maximum particle emission of 1.0g/kg and Nelson City Council requires 1.5g/kg.⁵ To avoid duplication the two councils have an arrangement whereby Environment Canterbury authorises burners emitting less than 1.0g/kg and Nelson City Council adopts that list and also authorises burners emitting between 1.0 and 1.5g/kg. The Ministry for the Environment publishes a list of all wood burners authorised by both Environment Canterbury and Nelson City Council – this is called the ‘authorised list’.

In addition to this, the Ministry published a ‘tested list’ of wood burners. These were burners for which a certificate had been provided to the Ministry by an accredited laboratory demonstrating emissions and efficiency in accordance with the national environmental standards.

The fundamental difference between the lists was that wood burners on the tested list have been tested by an approved laboratory, which, on the basis of those test results, provided a certificate to the Ministry that the burner meets the NES. (In some cases, however, the test certificate was based only on an opinion of the laboratory and not a full test. This provides no certainty that the burner was actually compliant.) Wood burners on the authorised list have undergone a more stringent approval process to be specifically approved by organisations such as Nelson City Council or Environment Canterbury. During this approval process, issues such as tamperability have been considered, as well as a physical inspection of the wood burner (design verification test) and a review of all its documentation (eg, installation and operating instructions).

Technically, a design verification test that reveals any departure from the authorised design therefore, indicates a burner that is not authorised for installation in that region.

1.4 Project overview

This performance review incorporated both design verification testing as well as full emissions and efficiency testing. The review consisted of two phases:

• Phase 1: design verification testing, in-store, of 35 wood burners

• Phase 2: purchase of 10 wood burners by the project partners, followed by design verification testing, and then emissions and efficiency testing in accordance with AS/NZS 4012/4013 in an accredited laboratory.

All burners were randomly selected for inclusion. This report describes the process and the results obtained for Phase 1 of the performance review. A report on Phase 2 is expected in late 2007.

The project was initially managed by Glenn Seymour of Strategic Energy Ltd. Glenn also authored the first draft of this report. Design verification work was carried out by John Yolland of John Yolland and Associates, consulting engineers.

1.5 Project partners

Environment Canterbury and Nelson City Council are national leaders in regulating wood burners. It was, therefore, appropriate for the review to be carried out in partnership with these councils. The Ministry provided the funding for the project, with Environment Canterbury and Nelson City Council providing considerable resources in kind (staff with relevant expertise in the testing and approval of low-emission wood burners).

In undertaking such a review it was to be expected that compliance issues could arise, particularly considering the industry was previously unregulated in most areas of New Zealand (ie, there were no emission limits other than the voluntary limits present in AS/NZS 4013:1999). It was also important that such a review provide transparency and fairness to the industry. The Ministry met with the New Zealand Home Heating Association (NZHHA) executive and manufacturers in April 2006 to outline the intention to carry out a performance review. At that time a date for the review was not specified. Industry therefore had no warning other than general notice that a review would be undertaken at some stage in the next two years.

1.6 Industry input

The Ministry also extended the opportunity for NZHHA to provide technical input into the design of the review. The NZHHA formally endorsed the review and offered their support by providing:

• co-operation in making burners in retail showrooms available for inspection (design verification testing only)

• co-operation in making test reports available

• informing all members (particularly retailers) of the upcoming review

• technical input into the design of the review protocol.

In addition to this, a sub-committee was set up to help develop a protocol to govern the performance review (discussed in more detail in Section 2). The Ministry acknowledges that such input was at company expense and would like to thank the following participants for their time and input to the review protocol:

• Ed Hawkes, National Secretary, NZHHA

• Ian Gallaugher, Technical Manager, BBQ Factory

• Phil Allen, Technical Manager, MetalFab (now Glen Dimplex)

• Evan Harris, Managing Director, Harris Flame Technology.

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