For manufacturing and food and beverage companies in the Philippines, greenhouse gas (GHG) accounting is becoming an important part of sustainability reporting. Yet preparing a complete inventory can be challenging, especially when supplier information is limited, operations rely on fossil fuels, or emissions data is spread across different departments.

A review of common gaps identified in 2025 sustainability reports points to five areas where companies can strengthen their inventories. The good news is that improvement does not always require expensive software or perfect data from the start. Small, well-documented steps can make emissions reporting more reliable and useful for business decisions.

1. Start measuring Scope 3 emissions

Many companies have started measuring emissions from their own operations and purchased electricity, known as Scope 1 and Scope 2. However, emissions from the wider value chain, classified as Scope 3, may remain unreported or only partially measured.

For manufacturers and food and beverage companies, these emissions can come from raw materials, packaging, freight, waste disposal, business travel, and employee commuting.

Where to start: Use existing purchasing and accounting records to estimate emissions from relevant activities. A spend-based method, for example, estimates emissions by multiplying the amount spent on a good or service by an appropriate emissions factor.

Treat these calculations as initial estimates, document the assumptions, and identify the three to five categories likely to contribute most to your footprint. You can then prioritize better data collection from suppliers and logistics providers.

You do not need to contact every supplier before beginning. Start with the areas that matter most and improve the estimates as better information becomes available.

2. Make reporting boundaries clear

A GHG inventory should explain which parts of the business are included. However, recently acquired facilities, joint ventures, outsourced production, and other operations may be excluded because of reporting limitations or incomplete data.

Without a clear explanation, readers may not understand how much of the business the inventory actually represents.

Where to start: List the facilities and operations included in your inventory, identify significant exclusions, and explain why they are excluded. Set a realistic timeline for improving coverage.

For example, a company could disclose that its inventory currently covers its owned manufacturing facilities, while emissions data from contract manufacturers is still being developed.

The important thing is to be transparent about current limitations and show how they will be addressed. The appropriate accounting treatment will depend on the company’s organizational boundary and the applicable GHG reporting framework.

3. Reduce fossil fuel use through practical improvements

Coal-fired boilers, diesel generators, and other fuel-burning equipment can be important sources of direct emissions. Given this industry, replacing these systems may not be technically or financially feasible for every manufacturer.

However, companies can take practical steps to reduce fuel waste while evaluating longer-term  alternatives.

Where to start: Monitor fuel consumption for major equipment, maintain boilers and generators, inspect steam traps and insulation, and assess opportunities for heat recovery. Track fuel use per tonne of product, where appropriate, to understand whether production is becoming more energy-efficient.

Companies can also assess options such as biomass, industrial heat pumps, electrified heating, and renewable electricity where these are technically suitable and commercially viable.

The first goal is to understand where energy is being used inefficiently, reduce avoidable consumption, and build the data needed to evaluate future investments.

4. Make emissions calculations easier to check

Changes in emission factors, inconsistent units, missing records, and changes in reporting boundaries can make emissions totals difficult to compare from one year to the next.

These issues can also make it harder for management to determine whether reported changes reflect actual improvements or simply changes in calculation methods.

Where to start: Maintain a standardized GHG calculation workbook with separate records for activity data, emission factors, calculations, and final results. Record each data point’s source, reporting period, unit, and responsible department.

Use consistent calculation methods and document any changes. If a revised boundary or methodology affects previous results, explain the change and restate historical figures where appropriate under the reporting framework.

A simple rule can help: whenever a reported number changes, explain whether the reason is a change in activity, data quality, methodology, emission factors, or business coverage.

5. Set realistic, measurable reduction targets

Some companies may not yet have emissions reduction targets, while others may announce long-term ambitions without a sufficiently developed inventory or clear implementation plan.

Targets are more useful when they are based on a reliable baseline and linked to actions the company can take.

Where to start: Establish your Scope 1 and Scope 2 baseline, identify the largest emission sources, and set measurable near-term targets. These could include reducing fuel use per unit of production, improving boiler efficiency, or increasing renewable electricity procurement.

Once the inventory improves, expand the targets to cover priority Scope 3 categories, such as purchased materials, packaging, and transportation. Longer-term net-zero or science-based targets can be considered as the company’s data and reduction plans mature.

For example, a company might aim to reduce Scope 1 and Scope 2 emissions intensity by 10% per unit of production by 2030, using 2026 as its baseline. Such a target should be supported by a defined calculation method, feasible reduction measures, and regular progress tracking.

From reporting gaps to practical progress

Improving a GHG inventory does not mean fixing every gap at once. Manufacturers and food and beverage companies can begin with existing records, establish consistent calculation methods, clarify their reporting boundaries, and gradually expand their coverage of value-chain emissions.

These improvements can strengthen the credibility of sustainability reports while helping businesses identify opportunities to reduce energy costs, engage suppliers, and prepare for changing customer expectations.

A reliable GHG inventory is not just a record of emissions. It is a practical tool for understanding your impact, setting realistic goals, and deciding what to improve next.