Emission Reduction Calculator Formula
Understand the math behind the emission reduction calculator. Each variable explained with a worked example.
Formulas Used
Reduction Achieved
reduction_pct = pct_reductionAbsolute Reduction
abs_reduction = absolute_reductionRemaining to Target
still_needed = remaining_to_targetTarget Reduction %
target_pct = (baseline_tons - target_tons) / baseline_tons * 100Variables
| Variable | Description | Default |
|---|---|---|
baseline_tons | Baseline Annual Emissions(metric tons CO2e) | 500 |
current_tons | Current Annual Emissions(metric tons CO2e) | 350 |
target_tons | Target Emissions(metric tons CO2e) | 250 |
absolute_reduction | Derived value= baseline_tons - current_tons | calculated |
pct_reduction | Derived value= (baseline_tons - current_tons) / baseline_tons * 100 | calculated |
remaining_to_target | Derived value= current_tons - target_tons | calculated |
How It Works
How to Calculate Emission Reductions
Tracking emission reductions helps measure progress toward climate goals.
Formula
Reduction % = (Baseline - Current) / Baseline * 100
Absolute Reduction = Baseline - Current
Baseline is typically a reference year (e.g., 2019) against which progress is measured. Targets are often set as percentage reductions from that baseline.
Worked Example
A company had 500 tons CO2e baseline, currently emits 350 tons, targeting 250 tons.
- 01Absolute reduction: 500 - 350 = 150 metric tons CO2e
- 02Reduction achieved: 150 / 500 * 100 = 30%
- 03Remaining to target: 350 - 250 = 100 metric tons CO2e
- 04Target reduction: (500 - 250) / 500 * 100 = 50%
Frequently Asked Questions
What is a good baseline year?
Most organizations use 2019 as a baseline since it represents pre-pandemic operations. The Science Based Targets initiative recommends a baseline no older than 2015.
What reduction targets are considered science-based?
The SBTi requires at least 4.2% annual linear reduction for 1.5C alignment and 2.5% for well-below 2C, typically aiming for 50% reduction by 2030.
Should I use absolute or intensity-based targets?
Absolute targets (total tons reduced) are preferred for climate impact. Intensity targets (per unit of revenue or product) can complement by accounting for business growth.
Ready to run the numbers?
Open Emission Reduction Calculator