From a34151767f454daa6c8a67f7f199b30c1220a7c9 Mon Sep 17 00:00:00 2001
From: nawaaaaaAaar <198336470+nawaaaaaAaar@users.noreply.github.com>
Date: Mon, 5 Oct 2026 16:13:35 +0000
Subject: [PATCH] Preserve explicitly provided zero carbon intensity factors

---
 codecarbon/core/emissions.py        |  4 ++--
 tests/test_zero_carbon_intensity.py | 34 +++++++++++++++++++++++++++++
 2 files changed, 36 insertions(+), 2 deletions(-)
 create mode 100644 tests/test_zero_carbon_intensity.py

diff --git a/codecarbon/core/emissions.py b/codecarbon/core/emissions.py
index 3b2f10fad..12fe42a62 100644
--- a/codecarbon/core/emissions.py
+++ b/codecarbon/core/emissions.py
@@ -335,7 +335,7 @@ def _global_energy_mix_to_emissions_rate(energy_mix: Dict) -> EmissionsPerKWh:
             in Kgs.CO2 / kWh
         """
         # If we have the chance to have the carbon intensity for this country
-        if energy_mix.get("carbon_intensity"):
+        if energy_mix.get("carbon_intensity") is not None:
             return EmissionsPerKWh.from_g_per_kWh(energy_mix.get("carbon_intensity"))
 
         # Else we compute it from the energy mix.
@@ -353,7 +353,7 @@ def _global_energy_mix_to_emissions_rate(energy_mix: Dict) -> EmissionsPerKWh:
                 carbon_intensity_for_type = carbon_intensity_per_source.get(
                     energy_type[: -len("_TWh")]
                 )
-                if carbon_intensity_for_type:  # to ignore "total_TWh"
+                if carbon_intensity_for_type is not None:  # to ignore "total_TWh"
                     carbon_intensity += (
                         energy_per_year / energy_sum
                     ) * carbon_intensity_for_type
diff --git a/tests/test_zero_carbon_intensity.py b/tests/test_zero_carbon_intensity.py
new file mode 100644
index 000000000..be8e95f15
--- /dev/null
+++ b/tests/test_zero_carbon_intensity.py
@@ -0,0 +1,34 @@
+from unittest.mock import patch
+
+import pytest
+
+from codecarbon.core.emissions import Emissions
+
+
+@pytest.mark.parametrize("intensity", [0, 0.0, 42.0])
+def test_explicit_carbon_intensity_is_used(intensity):
+    with patch(
+        "codecarbon.input.DataSource.get_carbon_intensity_per_source_data",
+        side_effect=AssertionError("Source factors should not be needed"),
+    ):
+        rate = Emissions._global_energy_mix_to_emissions_rate(
+            {"carbon_intensity": intensity}
+        )
+    assert rate.kgs_per_kWh == intensity / 1000
+
+
+@pytest.mark.parametrize(
+    "mix,expected",
+    [
+        ({"total_TWh": 1, "wind_TWh": 1}, 0.0),
+        ({"total_TWh": 2, "wind_TWh": 1, "coal_TWh": 1}, 0.4),
+        ({"total_TWh": 1, "coal_TWh": 1}, 0.8),
+    ],
+)
+def test_zero_source_factor_counts_toward_energy_coverage(mix, expected):
+    with patch(
+        "codecarbon.input.DataSource.get_carbon_intensity_per_source_data",
+        return_value={"wind": 0, "coal": 800, "world_average": 475},
+    ):
+        rate = Emissions._global_energy_mix_to_emissions_rate(mix)
+    assert rate.kgs_per_kWh == expected