As facilities with refrigeration and air-conditioning (RAC) systems or heating, ventilation and air conditioning (HVAC) systems begin efforts to reduce greenhouse gas emissions, additionality will be used to determine the effectiveness of their changes. The formula compares business as usual prior to implementation with the levels of emissions after a greenhouse gas reduction project is in place.

Before a greenhouse gas reduction project is implemented, a monitoring and verification (M&V) plan must be developed to quantify and verify results. The additionality metrics included in the plan should explain when, how and who will be conducting the monitoring and verification process. Generally, software developed by specialists in the area is used to streamline the M&V process.

Many facilities that use refrigerant conduct a project specific assessment to determine additionality. This method evaluates greenhouse gas reduction projects on an individual basis by creating a baseline of emission levels before the project is in place. After the project is implemented, the emission levels are compared to the baseline to determine actual reduction in greenhouse gas emissions.

Specific industries have specific performance assessments, as used to determine additionality. For example, heating, ventilation and air-conditioning system manufacturers or refrigeration and air-conditioning system manufacturers may measure performance improvements as compared to existing standards. This will apply for particular appliances or processes in relation to the reduction of greenhouse gas.

Additionality plays an important role in determining the effectiveness of any reduction project. Global climate change is severely impacted by greenhouse gas emissions. Numerous industries are affected by greenhouse gas offsets projects in all sectors, just a few examples including renewable energy efforts, reforestation and methane capture and recovery in landfills.

It is essential that businesses account for the benefits of a greenhouse gas reduction program. Additionality criteria must be established in order for it to be a true emissions reduction. Monitoring and verification ensure that reductions are real and sustainable. Many facilities involved in the development of methods to reduce their usage are relying on monitoring and tracking software and web-based applications that have been developed by experts in this area.

Part of any additionality equation is an examination of how permanent the project will be and a determination of any risk factors involved. The issue of leakage should be addressed and properly accounted for through monitoring and verification.

There is much discussion in the U.S. and other foreign countries as to whether funding should be made available to companies to enact programs aimed at reducing greenhouse gas emissions. Currently, a benchmarking system and protocols for certain industry sectors are under development. Determination of funding would rely on additionality to show how the project goes well beyond business as usual improvements. For example, if a project would have occurred anyway as part of a business improvement, then funding credits would not be awarded.