The Comparison Grid in eTool helps users evaluate and compare the environmental impacts of different energy and resource grids side by side. It can help the users to make a more informed decision based not only on the current grid but also the future projections as the user can choose a decarbonising grid for the comparison.
Note that this feature is not just limited to comparisons with a decarbonised grid but can be used to compare any grid with each other. However we recommend using this feature for comparing decarbonised scenarios.
Grid Comparison Feature in eTool
You can find this feature in the Project level under the ‘Site Attributes’ tab. Under the Default Grid/Network section, you’ll have the following grid selection fields:
- People and Equipment Grid/Network
- Operational Comparison Grid/Network
People and Equipment Comparison Grid/Network
The impacts of construction activities, equipment use, and water consumption are typically calculated based on the energy and fuel usage, alongside their respective carbon intensities. However, as the grid decarbonises over time, these intensities will reduce, and consequently, the construction impacts will also decrease. This feature enables users to compare the life cycle assessment (LCA) impacts of a project side by side, contrasting the impacts based on both the current grid and a decarbonised grid.
The ability to compare the two grid scenarios provides a more comprehensive view of how using electrical equipment will provide even more carbon savings based on the future decarbonisation. For instance, when replacing fossil fuel-powered equipment with electric alternatives, the carbon savings will be higher during the use phase and end-of-life phase because the grid intensity will be lower at the time of replacement or repair.
For example, if a building’s external driveway is replaced at year 30 using electric-powered equipment, the comparison grid will calculate the carbon impacts based on the projected grid intensity in year 30. This means that the carbon savings associated with the electric equipment will be greater since the grid’s carbon intensity will be much lower at that point, reflecting the cleaner energy mix that will likely be in place by that time. It is important to note that if no equipment relies on the electric or gas grids after the initial construction phase, the results for both the default and comparison grids will remain the same.
The people and equipment comparison grid will affect the embodied carbon impacts, including transport and equipment emissions for Modules A, B, and C (excluding B6/B6+ and B7/B7+), based on the selected electricity, gas, and water grids.
Operational Comparison Grid/Network
The Operational Comparison Grid allows users to compare the ongoing energy, gas, and water impacts of a building or infrastructure project under two different grids: for example, the current grid and a decarbonised grid. The flexibility of this tool means users are not limited to just comparing with the decarbonised grid, but the comparison can be done based on any two grids. If the goal is to compare the use phase and end-of-life phase impacts based on the NSW grid and the Victorian grid, that can be done as well.
The operational comparison grids affect the impacts for Modules B6/B6+ and B7/B7+.
If users wish to compare only embodied or only operational impacts, they can adjust the relevant grids while keeping the other comparison grids set ‘None’ (example below).
Reporting
Once the comparison grid(s) have been specified, the results will be reported in the ‘All Impact Details’ report under the ‘Data’ sheet which will have the results for the default grid as well as the comparison grid. All of the selected indicators will be reported for both default as well as comparison grids and the headers for the comparison grid will have “Comparison -” as a prefix to the reported indicator.
Related Posts:
- Decarbonised Grid Scenarios
- Future Grid Sensitivity
- Green Star Buildings: Decarbonisation of Future Grids
