Check that a decomposition sums to its parent

Add only the rows whose parent_relation is sums_to_parent, and compare that sum with the parent row: never add the parent to its own children. For ADEME's butane (Europe, per kWh), the 2014 vintage splits exactly, 0.22968 + 0.0378 = 0.26748 kg CO2e per kWh.

The query#

A decomposition shares one root_slug. This query lists the parent and its children for every vintage, with the sum of the children beside each row.

SELECT reference_year,
       system_boundary,
       parent_relation,
       is_top_parent,
       value_co2e_native,
       round((sum(value_co2e_native) FILTER (WHERE parent_relation = 'sums_to_parent')
              OVER (PARTITION BY reference_year))::numeric, 5) AS children_sum
FROM open_ef.factors_flat
WHERE library = 'ademe'
  AND root_slug = 'ef-ademe-butane_maritime_included-europe-kwh-well_to_use-53be0cf1'
  AND is_default_indicator
ORDER BY reference_year, is_top_parent DESC, system_boundary;

The 2014 vintage adds up to the parent exactly. The 2019 vintage, the current default, is off by 0.0002 because the publisher rounds each printed figure on its own. Treat a gap of that size as rounding, and report the parent's printed total.

The query filters on is_default_indicator but not on is_latest_activity_year, so that both vintages show. To read one vintage only, add AND is_latest_activity_year (the current one) or a year filter, as in Get the value for a past year.

Why it works#

Why it works. The parent row (is_top_parent, no parent_relation) is the total. combustion and upstream_fuel are parts of it. Filtering on parent_relation = 'sums_to_parent' adds the parts and leaves the total out. Summing every row of the root_slug would count the butane twice.

Watch out. Only sums_to_parent children are addends. A contained_by_parent child is a nested envelope, a smaller boundary inside the parent's, so it is not a part to add, and a reported_beside_parent row (EN 15804 module D) is reported next to the total and never added to it. In any aggregate over many factors, keep WHERE is_top_parent so that no child is counted beside its parent.

Which total to report#

The two parts exist because reporting standards disagree on where the line falls. Under the GHG Protocol, combustion is Scope 1 and the upstream part is Scope 3.3, reported apart. ISO 14083 wants the well-to-use total. On factors_flat, is_top_parent AND system_boundary = 'well_to_use' gives the ISO 14083 view, and the GHG Protocol view is that parent's parent_relation = 'sums_to_parent' children, reported apart. Do not read NOT is_derived as the GHG Protocol filter: it only says the publisher printed the total itself, which ADEME does and DESNZ does not.

Related#

• Parents, children, double counting
• System boundaries
• Glossary: sums to parent, contained by parent, derived total
• ADEME butane factors in factor search and ADEME's methodology