1 About

1.1 Citation

If you wish to use any of the material from this report please cite as:

  • Ben Anderson (2019) NZ GREEN Grid Household Electricity Demand Data: EECA Data Processing (Part A) Report v1.0, Centre for Sustainability, University of Otago: Dunedin.

This work is (c) 2019 the authors. Usage right are specified in the License section (1.3).

1.2 Report circulation

  • Public – this report is intended for publication following EECA approval.

1.3 License

This work is made available under the Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) License.

This means you are free to:

  • Share — copy and redistribute the material in any medium or format
  • Adapt — remix, transform, and build upon the material for any purpose, even commercially.

Under the following terms:

  • Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
  • ShareAlike — If you remix, transform, or build upon the material, you must distribute your contributions under the same license as the original.
  • No additional restrictions — You may not apply legal terms or technological measures that legally restrict others from doing anything the license permits.


  • You do not have to comply with the license for elements of the material in the public domain or where your use is permitted by an applicable exception or limitation.
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For the avoidance of doubt and explanation of terms please refer to the full license notice and legal code.

1.4 History

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1.5 Support

This work was supported by:

  • The New Zealand Energy Efficiency and Conservation Authority (EECA)

2 Introduction

This report uses the full New Zealand GREEN Grid household electricity demand study research data to:

  • test the feasibility of multi-year data analysis beyond the single year made possible by the public available data (Stephenson et al. 2017);
  • impute total dwelling load (W) per minute using the original circuit level data;
  • produce a smaller mean half-hourly power demand (W) per circuit (and total load) per dwelling dataset for further analysis;
  • extract half-hourly data for specified circuits.

This report describes the results of this work and directs the reader to relevant R code where necessary.

All code used to create this report is available from:

The archived and most recent version of the report is available from:

3 Data

The NZ GREEN Grid household electricity demand study recruited a sample of c 40 households in each of two regions of New Zealand (Stephenson et al. 2017). The first sample was recruited in early 2014 and the second in early 2015. Research data includes:

  • 1 minute electricity power (W) data was collected for each dwelling circuit using GridSpy monitors on each power circuit (and the incoming power). The power values represent mean(W) over the minute preceding the observation timestamp;
  • Dwelling & appliance surveys;
  • Occupant time-use diaries (focused on energy use).

The data collection was supported by the New Zealand Ministry of Business, Innovation and Employment (MBIE) through the Renewable Energy and the Smart Grid (GREEN Grid) grant (Contract ID: UOCX1203).

4 Multi-year data availability

Whilst the GREEN Grid project collected data from 2014-01-06 to 2018-08-01, we do not have complete multi-year coverage of the 45 dwellings for whom data exists.

As Figure 4.1 shows data is available for most of the 24 dwellings in the Taranaki region from mid 2014 and for most of the 20 dwellings in Hawkes Bay from early 2015. In most cases the ‘right’ number of observations were received per half hour (30) when the dwellings were sending data. However not all dwellings sent data continuously with substantial attrition by 2017 (Figure 4.2).