The scope of the EnergyScape (parent) project was subtly different to the hydrogen options and bioenergy options sub-projects, but all three projects had similar phases of work and applied similar methodologies during their development. Before addressing the methodologies used in the EnergyScape projects, we need to define two concepts:
- Energy pathway - An energy pathway is the thread that connects an energy resource as it is supplied through various conversion and distribution infrastructures to the application demanded by an end-user. Figure 1 provides an example of such an energy pathway; from wind to passenger-kilometres via the generation and transmission of electricity and end-use in an electric vehicle.
- Energy assets - An energy asset is any discrete component of an energy pathway e.g. a wind farm, transmission grid from Waikato to Auckland, a coal mine etc. Each asset can have a defined capacity, cost and life-time etc.
Here we review the five basic project stages:
Stage 1: Identification and review of energy pathway options
In order to assess and define the characteristics of all New Zealand’s current and potential (future) energy pathways, it was first necessary to map out how all resources, conversion systems, distribution systems and end-use options could be linked together. The resulting map was called the pathway map.
The next task was to describe all of the identified energy assets in a ‘consistently formatted’ manner, independent of the type of asset. To achieve this we documented the characteristics of all the assets in the New Zealand Energy Asset Database, and then described the status and barriers for all their associated technologies and energy resources in the. It should be noted that obtaining perfectly verified and up to date data / assessments for all assets was not the objective of this project. Rather, the intention was to provide enough credible data to provide a good ‘order or magnitude’ assessment of New Zealand’s current and future assets.
In order to provide some structure to the documentation, the energy pathways were broadly grouped into: “renewable resources” (solar, wind, hydro, marine etc); “earth resources” (geothermal, oil, gas, coal, nuclear etc.), “bioenergy resources” (animal and plant based biological waste streams); “distribution infrastructure” (road, rail, shipping & aviation transportation, and, oil, gas, coal & electricity distribution networks etc.); “secondary conversion” (energy conversion systems and processes that are not directly connected with a primary energy resource e.g. gas to liquids, petroleum refining); and, “hydrogen options”.
Because the potentials of many renewable resources in New Zealand have not been investigated under a commonly defined methodology, this project was obliged to develop one. The resulting methodology comprised the following items and concepts:
- Generation of the resource’s potential energy map by evaluating the energy that could be captured / extracted using a generic or dominant capture / extraction system (e.g. conventional bore drilling systems for oil resource extraction and horizontal-axis wind turbine devices for wind energy capture) and mapping the physical location of the resource. These Geographic Information Systems (GIS) maps present the potential of each energy resource, spatially, using the most appropriate units of energy measurement.
- Consideration of the barriers and limitations linked to the exploitation and development of a particular energy resource (e.g. geographical accessibility, distance from existing distribution grids and urban centres etc.), such that the potential energy maps can be filtered to present only the feasibly realisable energy maps.
- Tabulation of the realisable potentials for each resource into potential assets (e.g. the possible number of 20 MW wave energy farms that could be deployed over the national wave energy resource).
- Those resources that also fall within the Maori kaitiakitanga (guardianship) are identified on the maps.
Stage 2: End-use characterisation
It is well understood that the demand for energy services drives the development of extraction, distribution and supply infrastructure, i.e. if the demand didn’t exist, there would not be a revenue stream for the infrastructure. As more conversion technologies become available and the costs of accessing existing resources increase, the energy resources available to meet end-user demands become diversified (e.g. home heating can be achieved using passive solar, gas-burning, wood-burning, or electricity based heating systems).
In order to characterise the end-user demand in the future, the EnergyScape project had to classify demand by end-user “service” rather than by the type of conventional fuel used for that service at present (e.g. demand for transport services was determined in terms of passenger-kilometres travelled by the end-user rather than by the volume of diesel and petrol consumed by the service).
The methodology for forecasting future end-use demand is described in the first section of the EnergyScape Asset Review, and, tabulated results of the end-use demand, by service sub-sector and by region, appear in the New Zealand Energy Demand Database.
Stage 3: Pathway analysis (energy, economic and emissions)
The EnergyScape project needed an analysis tool for calculating and depicting the complex interactions occurring between energy resources, extraction / conversion / distribution assets and end-use demands. The Long-Range Energy Alternatives Planning (LEAP) software tool, developed by the Stockholm Environment Institute-Boston (www.sei-us.org), was selected for this purpose. In trialling this tool, a basic LEAP model was developed by inputing Energy Data File level data. that was capable of depicting the New Zealand energy system at a relatively low level of detail, whilst demonstrating its capacity to calculate and display a wide range of energy, economic and emissions parameters. This basic model demonstrates the flexibility of LEAP for displaying the predicted time varying characteristics of a wide range of national data (energy and GHG emissions) by end-user service, energy resource type and future environment scenario.
Stage 4: Scenario modelling
After demonstrating the capacity of LEAP to calculate and depict energy pathway data, a comprehensive model with regional differentiation was developed. The challenge for the EnergyScape team was to import information from the Energy Asset and Energy Demand Databases into the complete LEAP model. To enable rapid input of data updates and more in-depth analysis of output, a series of LEAP interface tools were developed. The interface tools included:
- NZEAD to LEAP interface – which passes data from the Energy Asset Database to LEAP
- NZEDD to LEAP interface – which passes data from the Energy Demand Database to LEAP
- LEAP viewer – which is a Labview tool that enables interrogation of LEAP models from external websites
- Scenario evaluation tool – which is an excel file used to graphically display results of LEAP modelling
- Sankey diagram generator – which enables visualisation of energy systems in Sankey diagram format
We called the combined package of tools, the “EnergyScape framework”. This framework allows you to select various combinations of energy pathways to meet a forecast end-user demand for energy services (from various energy resources) according to three defined future environment “scenarios”. Since this project only seeks to demonstrate the functionality of the analysis tool developed. These future environment scenarios were created to demonstrate the versatility of the EnergyScape framework; they do not represent suggested or expected national energy system directions.
Stage 5: Gap analysis
The process of pulling together a comprehensive energy pathway evaluation tool is bound to generate insights into system vulnerabilities and knowledge gaps. The project captured these insights in three ways:
- Colour coding the state of knowledge for all processes in the pathways map
- Indentifying status of research for each chapter in the asset review
- Capturing observations in the ‘summary of findings’ document.
The later document identifies gaps in the knowledge base of the EnergyScape framework that weaken its ability to provide valid results and feasible solutions to New Zealand’s envisioned future energy systems. The results of three scenarios (Continuity, Political and Alternative) will be characterised in terms of: magnitude of demand and supply gaps, resource and infrastructure maturity, capital cost profile, implementation and operating risk and environmental impacts.
Sensitivity and risk analyses will be undertaken and these will check: technical risks, research risks, magnitude of demand and supply gaps, resource and infrastructure maturity, national energy security, price volatility and environmental impacts.
The EnergyScape framework will be will be constructed in a manner that its various inputs can be updated, and, thus, it can track research priority as new developments take place.
Stage 6: Supporting research strategy development
Leveraging of the strengths of the EnergyScape team, a weighted-score research prioritisation tool was developed to facilitate a more robust and mechanistic methodology for defining New Zealand’s energy research strategy. The usefulness of the prioritisation tool was verified by pre-populating the matrix with research needs as identified in the EnergyScape asset review, and discussing the outcomes in a two day workshop. By combining the analysis and insights derived from developing the EnergyScape platform with the preliminary results of the research prioritisation matrix, some suggestions regarding priorities of national public good research priorities (as compared to private and international research) could be made.