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Key Initiatives
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ICAO Carbon Emissions Calculator (ICEC)
  • ICEC API
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FAQ

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 Title : 1. Why does ICAO not take account of non-CO2 effects in the methodology?  ‎(1)

The ICAO Carbon Emissions Calculator is limited to the calculation of the CO2 amounts released into the atmosphere by the aircraft engines during a flight. Consequently, the ICAO Emissions Calculator does not quantify the climate change impact of aircraft emissions using the Radiative Forcing Index (RFI) or other such multipliers. The scientific community has not yet reached consensus on the use of the RFI or other such multipliers and therefore ICAO will only adopt a multiplier if and when the scientific community reaches a general agreement on this issue. ICAO is working in collaboration with IPCC on this subject and will adapt a multiplier methodology in due course accordingly. 
 
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 Title : 2. What is offsetting? ‎(1)

In general terms, an offset is a “compensating equivalent”. As an activity, it can mean to “cancel out” or “neutralise” emissions from a sector like aviation by financing or creating equivalent emissions reductions in a different activity or location.
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 Title : 3. Why doesn’t ICAO provide an offsetting scheme on its website? ‎(1)

ICAO notes the positive contribution that offsetting makes to the mitigation of greenhouse gas emissions through carbon markets, and its role in consumer education. The voluntary offset market has undergone rapid growth in the last few years, producing a wide variance in the quality of offset credits and some public confusion about their role. As a member of the United Nations, ICAO cannot recommend specific services offered by commercial entities. However, the answers to the questions below may help individual travelers to select the best means to offset their air travel CO2 emissions.
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 Title : 4. What should I look for in an offset scheme? ‎(1)

While ICAO cannot recommend a specific offset provider, there are factors that you should consider in making your own selection, including:
  • How is my carbon offset credit generated?
  • Does it conform to recognised standards (and/or any guidance from governments)?
  • Has it been audited and verified?
  • Is it transparent?
     
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 Title : 5. How is my carbon offset credit generated? What different qualities do they possess? ‎(1)

Most credits are generated through investment in specific emission reduction projects. Although not an exhaustive list, the most common projects to invest in are bio energy and clean non-emitting electricity generation (for example, harnessing wind, solar, and hydro power). These projects not only generate credits but provide investment in renewable sources that reduce our long-term reliance on fossil fuels. As well as new technologies, maintaining the planet’s ability to absorb CO2 through nature is also important. For this reason forest-based carbon sequestration projects are also common and play an important role in tackling climate change, although some have doubts about the permanent carbon storage of such projects. Where a sequestration project is offered, look for information on how the forest is managed and risks are addressed. As a general rule, look for projects that provide evidence on how they contribute to sustainable development and whether they provide a genuine “additional” benefit (in other words, they finance projects that would otherwise have not taken place). This task is usually carried out for you where a project complies with a recognised standard. Also, you can also check to see whether any advice or information is provided by from local/national government.

Some companies and sectors have their emissions regulated and can be subject to a cap. Each regulated entity has a carbon allowance equivalent to the cap. Some offset providers offer the consumer the ability to purchase and cancel these allowances, forcing the regulated entity to make additional emission reductions to meet their cap.

 
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 Title : 6. Does it comply with a recognised standard? Has it been audited and verified? ‎(1)

Carbon credits can be generated through the Kyoto Protocol’s Clean Development Mechanism (CDM) and Joint Implementation (JI) [Ref. 1]  as Certified Emission Reductions (CERs). All CER projects satisfy rigorous quantification requirements to determine how many tonnes of GHG the project has reduced. The projects must also successfully complete an additionality assessment, contribute to sustainable development, and undergo third-party validation and verification of emission reductions before they are approved. The quality of Voluntary Emissions Reductions (VERs) is highly variable so they should be approached with appropriate caution. One indicator is compliance with ISO 14064 (Part 2, 2006) [Ref. 2] . ICAO does not offer any advice on national standards or other voluntary standards, although many provide a robust test.

 

[Ref. 1] Clean Development Mechanism allows emission-reduction (or emission removal) projects in developing countries to earn certified emission reduction (CER) credits, each equivalent to one tonne of CO2. These CERs can be traded and sold, and used by industrialized countries to a meet a part of their emission reduction targets under the Kyoto Protocol.

The mechanism stimulates sustainable development and emission reductions, while giving industrialized countries some flexibility in how they meet their emission reduction limitation targets. The projects must qualify through a rigorous and public registration and issuance process designed to ensure real, measurable and verifiable emission reductions that are additional to what would have occurred without the project. The mechanism is overseen by the CDM Executive Board, answerable ultimately to the countries that have ratified the Kyoto Protocol. UNFCCC website http://cdm.unfccc.int/about/index.html

Joint Implementation allows a country with an emission reduction or limitation commitment under the Kyoto Protocol (Annex B Party) to earn emission reduction units (ERUs) from an emission-reduction or emission removal project in another Annex B Party, each equivalent to one tonne of CO2, which can be counted towards meeting its Kyoto target.

Joint implementation offers Parties a flexible and cost-efficient means of fulfilling a part of their Kyoto commitments, while the host Party benefits from foreign investment and technology transfer. UNFCCC website http://unfccc.int/kyoto_protocol/mechanisms/joint_implementation/items/1674.php
 
 
[Ref. 2] Greenhouse gases -- Part 2: Specification with guidance at the project level for quantification, monitoring and reporting of greenhouse gas emission reductions or removal enhancements.
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 Title : 7. Is it transparent? ‎(1)

The degree of transparency about the offsetting program varies significantly between programs. Using schemes that are well documented make an informed choice possible. As a minimum, you should have sufficient information about the project to answer all of the above questions.
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 Title : 8. Can I calculate the monetary cost of my carbon emissions? ‎(1)

In general, the price of an offset credit is no guarantee of its quality. The price of a project credit is determined by the investment required to generate a carbon saving, and the administration cost. Project investment will vary by location and the nature of the project, even if the quality is the same. Administration costs also vary. Some projects claim to invest 100% of your money directly in projects, but somewhere between 80-90% is typical. In practice, there may be little difference as some schemes attribute overheads and verification costs directly to the project.

Like the carbon markets generally, prices can and do fluctuate. This makes it difficult to provide accurate information on the average price of carbon offset credits at any moment in time. Some indicative information can be found by looking at the trends in the carbon markets. Various carbon markets are in operation, some are mandatory like the European Union (EU) emissions trading scheme and others are on a voluntary basis.

 
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