Estimating Avoided Emissions
Developing a GHG Baseline is essential to estimating avoided emissions from the activities.
This can be achieved through using simplified calculations representative of the emissions reduction activities.
The avoided emissions estimate calculation provided here does not meet the requirements for reporting an enterprise baseline and emissions avoided for other purposes.
Emissions factors (EFs) are representative values or multipliers that convert an inventory input (e.g. fertiliser, daily feed intake) to the average amount of CO2 produced in its use. Estimating GHG emissions associated with land management activities are based on internationally agreed calculations and emissions factors. These agreed calculations are embedded into GHG Baselining tools.
To support your planning , estimates of avoided emissions that can be expected when implementing an activity can be made based on simplified calculations.
Avoided emissions (GHGavoided) can be estimated by comparing the difference in emissions between a ‘business-as-usual’ state (GHGBAU) and the emissions reducing activity (GHGactivity).
Avoided Emissions Estimate (AAE) Equation:
GHGavoided = GHGBAU - GHG activity
In the Pathfinder, we outline simplified calculations to estimate avoided emissions associated with some of the proposed activities. EFs or default values, are provided where appropriate. The simplified calculations are based on IPCC Tier 1 calculations, Australian defaults, and basic assumptions are provided to support farm assessments.
Nitrification Inhibitors (enhanced Fertiliser)
To estimate avoided emissions resulting from an EEF you will need the following data for both the baselineb and activitya scenarios:
|
F |
= |
Fertiliser application amount (kg) |
|
N |
= |
The proportion of nitrogen in the fertiliser for example, urea = 0.466 (see FAO Fertiliser specifications list) |
|
EF |
= |
Emissions Factor, Australian default = 0.0057 |
|
EFEEF |
= |
Emissions Factor estimate = 0.002 |
|
GWP |
= |
Global warming potential (265) |
Compared to the baseline calculation, the activity calculation should change the EF, the fertiliser application rate, and the proportion of N associated with the EEF.
GHGbase = Fb * Nb * EF * GWP
GHGactivity = Fa * Na * EFEEF * GWP
These calculations provide provide a simple indicator based on direct N2O emissions (kg CO2-e) and should then be applied to the AEE to estimate the GHG benefit. They do not account for indirect emissions (e.g. volatilisation, leaching).
See more on estimating avoided emissions: