Viet Nam

Historical emissions are based on PRIMAP data (Gütschow et al., 2021). Data may differ from CAT data in 2020 as it was based on government data sources (MNRE 2019; Viet Nam Government 2017b). LULUCF data is from the Biennial Report 3 (Viet Nam Government, 2020b).

To estimate historical emissions for 2020, we applied a gas-by-gas approach. For direct CO₂ emissions, we applied growth rates from Global Carbon Budget for the year 2020 (Global Carbon Project, 2020). We assume that the impact of the pandemic on other emissions will be minimal and so have extrapolated emissions for 2020 using a 5-year average from historic emissions.

The pledge emissions are found in Viet Nam’s updated NDC (Viet Nam Government, 2020a). The BAU scenario for GHG emissions assumes economic growth in the absence of climate change policies. The pledge emissions have economy wide coverage. The BAU starts from 2014 inventory data, with projections for 2020, 2025 and 2030. Interpolations were used in the years not reported. The updated NDC includes a breakdown of sectoral emissions. The CAT removes LULUCF to focus on the emissions intensive sectors of industry and energy.

The current policy scenario is based on projections from APERC (2019a) business as usual (BAU) scenario. The APERC BAU scenario projects CO₂ emissions of current and planned policies in the energy sector. The energy sector covers over 50% of Viet Nam’s emissions.

The APERC (2019a) BAU scenario has a number of assumptions: The optimisation and capacity of the power mix is based on the Revised PDP7. Electricity use from appliance and buildings reflect economic growth and urbanisation. Industry plays a key role in the economy, where steel, iron and cement industry continue to dominate the industry sector. Regarding transport, energy elasticity is linked to GDP consistent with the base year fuel mix. Biodiesel is not included as it assumes no market penetration of the product. It is assumed that increases in the number of vehicles continues. The energy supply mix matches the sectoral plans, including coal and natural gas targets, and LNG terminal plans. The production of oil is based on available reserves and historical data. The scenario projects a decrease in the use of biomass, but biomass is the main renewable energy source in the power sector. Energy is imported when demand is not met by domestic supply.

The APERC BAU scenario considers the Viet Nam National Energy Efficiency Program (VNEEP) phase one and two, the shift from traditional fuels to electrification, the National Technical Regulation on Energy Efficiency Buildings, and the Energy Efficiency Building Code technical standards. It does not include the recent VNEEP Phase three (MOIT, 2019) which would reduce energy demand (APERC, 2019b). In addition, the APERC BAU scenario was publish in 2019 and does not include any policies in 2020, such as Resolution 55, the extension of the solar feed-in-tariff, or solar auctions.

Current policy projections for energy non-CO₂ emissions are based on US EPA (US EPA, 2019) data.

Agriculture and waste emissions projections are based on the latest historical emissions with a trend from the growth rates of the US EPA (US EPA, 2019) non-CO₂ data.

Projections for LULUCF (when included) are based on historical data for year 2014 the Third National Communication and projections from the updated NDC with interpolations between unreported years (MNRE, 2019; Viet Nam Government, 2020a).

Current policy industrial processes emissions create an emissions range estimated by applying the average growth rate of the last historical year and the average growth rate of the last 5 years. Estimated emissions for this sector are substantial more than estimated for last year based on more recent historical data and these estimations.

The CAT rated Viet Nam’s overall rating and the current policies and actions as “Highly Insufficient” in September 2021, and “Critically Insufficient” in October 2021. The change is the result of a methodological change using more recent data sources rather than policies or actions. We strive to use the latest and most robust data sources, and more recent historical data has led to revisions to the current policies and actions pathway. Viet Nam is on the border of the “Critically Insufficient” rating and “Highly Insufficient” rating. Viet Nam could easily improve its rating by one category with further policy actions. This would likely tip the balance of Viet Nam’s overall rating to “Highly Insufficient”.

We applied a novel method to estimate the COVID-19 related dip in greenhouse gas emissions in 2020 and the deployment through to 2030. The uncertainty surrounding the severity and length of the pandemic creates a new level of uncertainty for current and future greenhouse gas emissions. We first update the current policy projections using most recent projections, prepared before the pandemic (as above).

We then distil the emission intensity (GHG emissions/GDP) from this pre-pandemic scenario and apply to it most recent GDP projections that take into account the effect of the pandemic. The CAT used the GDP from APERC to estimate the pre-pandemic emissions intensity (APERC 2019a).

To capture a wide range, we compare several GDP projections to account for the pandemic. The CAT compared scenarios from the IMF, the World Bank, the Asian Development Bank, and government projections (ADB, 2021; IMF, 2021; Jennings, 2020; World Bank, 2021). The CAT calculations are based on the largest range of scenarios available, and then choosing the maximum and minimum emissions out of all the scenarios to create a maximum and minimum range. The CAT applies the GDP growth rate of APERC to estimate GDP beyond the years that each scenario reported.

The CAT uses Global Warming Potential (GWP) values from the IPCC's Fourth Assessment Report (AR4) for all its figures and time series. Assessments completed prior to December 2018 (COP24) used GWP values from the Second Assessment Report (SAR).