The Principal Economics team collaborated with a large team of frontier researchers and practitioners and developed a transport appraisal methodology that is grounded in an accessibility framework and integrates travel behaviour, environmental impacts and economic principles.

The project sought to address limitations in the current appraisal methodology, which although well-established, has notable limitations. To address these, the research considered the pros and cons of six potential appraisal methodologies, drawing on the identified advantages of each to establish an access-based synthesised accessibility appraisal methodology as an alternative.

The synthesised methodology will improve land-use and transport policy integration. It:

Our team has applied the synthesised accessibility appraisal methodology to three case studies. A comparison of the outcomes produced by the synthesised accessibility appraisal methodology with those generated from a status quo appraisal highlighted the importance and usefulness of the new approach. The new methodology was shown to cohesively combine various components of land-use and transport policy, and provide transparent information for decision-makers, and demonstrated it could lead to significantly higher benefit–cost ratios if the potential benefits of transport projects and programmes are accommodated by permissive land-use policies.

The Emissions Reduction Plan 2 (ERP2) delineates Aotearoa New Zealand’s strategy to attain its emissions reduction objectives for the 2026-2030 period, alongside setting a path towards achieving long-term emissions reduction objectives. ERP2 aims to reduce annual average emissions from 72.5 MtCO2e to 61 MtCO2e. The Ministry for the Environment (MfE) engaged Principal Economics Limited, the Centre of Policy Studies, and Infometrics Limited to evaluate the comprehensive impact of the proposed policies. This includes:

• Assessing the comprehensive economic repercussions of emissions mitigation policy packages within ERP2.

• Estimating and understanding of secondary or indirect consequences.

• Carrying out distributional analysis of these ramifications.

The critical policies investigated in our report include:

• Increasing renewable energy through Electrify NZ

• Targeting 10,000 public EV chargers

• Lowering agricultural emissions

• Investing in resource recovery

• Improving public transport

• Investigating carbon capture, utilisation and storage.

Cite this article

Torshizian E, Adams P, Stroombergen A. 2024. Economic Impact of New Zealand’s Second Emissions Reduction Plan. Report to Ministry for the Environment by Principal Economics Limited in collaboration with the Centre for Policy Studies and Infometrics Limited.

Despite being one of the national priorities, there are still large gaps and no consensus from the literature on what drives house price growth and the interaction between major drivers that underpin house price growth. In our housing affordability knowledge hub, we provide:

• an independent review of the factors of house price growth (HPG) in New Zealand
• a range of descriptive statistics of the HPG and its drivers over the last fifty years.

Our review includes both the academic and grey literature. We provide a list of suggested future studies to improve our understanding of the factors of HPG in New Zealand.

Cite this article.

Principal Economics. (2021). Drivers of House Price Growth Knowledge Hub. Retrieved from Drivers of House Price Growth – Principal Economics.

Avoid costly delays in decision-making. For deep uncertainty, plan ahead, start small, and keep monitoring. Climate is beginning to exacerbate extreme “one-in-100-year” events. Our knowledge of the likelihood of these large-impact events happening in shorter intervals is limited. Adaptive Decision-Making can help to minimise the cost (from delays) to the economy through increasing flexibility at the planning phase. Our earlier work estimated the annual cost of delay to be equal to 18 per cent of the capital cost of projects.

Cite this article

Principal Economics. (2023). Climate change adaptation and investment decision making. Waka Kotahi NZ Transport Agency.

The Ministry for the Environment (MfE) appointed Principal Economics to review the Housing and Business Development Capacity Assessments HBAs). Our review included all councils’ HBAs, except for Rotorua and Wellington, which were not available at the time of this review. The focus of our review was on the requirements of the National Policy Statement on Urban Development 2020 (NPS-UD 2020). The outcome of our review indicates the areas of improvement for the next round of HBAs both for the councils and for the MfE and HUD (the ministries).

Reviews that have been published online can be found below:

• Dunedin – Otago Regional Council and Dunedin City Council.
• Futureproof – Waikato Regional Council, Hamilton City Council, Waikato District Council and Waipa District Council.
• Tasman – Tasman District Council.