The Rhode Island Department of Environmental Management (DEM) recently released its 2020 Greenhouse Gas Emissions Inventory, providing insights into the state’s progress on reducing emissions over the past 30 years. The report indicates that while the COVID-19 pandemic significantly reduced emissions in 2020, Rhode Island still has a way to go to make these drops an ongoing trend.

Overview of Emissions Trends

The 2020 inventory found that Rhode Island’s total greenhouse gas emissions were 9.24 million metric tons of CO2 equivalent (MMTCO2e) in 2020. This represents a 20.1% reduction compared to 1990 levels of 11.56 MMTCO2e. The reduction meets the Act on Climate’s first benchmark of 10% below 1990 levels by 2020. However, the report cautions that the pandemic drove an unusual one-year decline in emissions beyond what climate policies alone could achieve.

The transportation sector remains Rhode Island’s largest source of emissions, responsible for 38% of the 2020 total. But transportation emissions declined 11.6% from 2019 levels due to reduced aviation activity during lockdowns and less vehicle miles traveled. Emissions from electricity consumption comprised the second largest share at 20.6% of the total. However, electricity emissions notably increased 16.7% from 2019, attributed to changes in regional power generation impacts from the pandemic.

Over the past 30 years, Rhode Island has seen sizeable declines in some of its highest emitting sectors. Transportation emissions have dropped 18.9% since 1990 thanks to more fuel efficient vehicles. Electricity emissions are down 27.5% due to the growth of renewable energy and natural gas power displacing dirtier coal and oil generation. Residential heating emissions have declined 19.8% as homes become more efficient and transition from oil to natural gas or electricity.

Emissions Impacts of the COVID-19 Pandemic

The report emphasizes that the 2020 emissions inventory reflects unique pandemic impacts that reduced emissions beyond typical expectations. Transportation saw the clearest pandemic-driven effects. Aviation emissions plummeted 79.6% in 2020 compared to 2019 levels. Overall highway vehicle emissions declined 7.3% reflecting less commuting and travel during lockdowns.

The pandemic also contributed to a warmer than average winter in 2020, reducing heating fuel demand. Residential heating emissions fell 8.5% and commercial heating dropped 6.8% from 2019. Limited industrial activity and closure of many businesses and commercial spaces also contributed to lower electricity use and emissions.

The report cautions against interpreting the 2020 inventory as indicative of future emission trends, however, 2020 provides an important benchmark of progress towards Rhode Island’s 2050 goal of net zero emissions.

Progress on Renewable Energy Goals

The inventory report also tracks Rhode Island’s efforts to transition its electricity supply to renewable sources. In 2020, the state retired 6.3% more Renewable Energy Certificates (RECs) compared to 2019. Rhode Island’s Renewable Energy Standard sets a goal of 38.5% renewable electricity by 2035.

The report notes that 2020’s electricity emissions total of 2.04 MMTCO2e includes 1.75 MMTCO2e from renewable sources considered carbon neutral under the RES. While biomass carbon neutrality remains controversial globally, Rhode Island follows federal bioenergy carbon accounting in its inventory. Efforts to increase additional solar, wind, and other renewable generation will be key to driving further emissions reductions from the electricity sector.

Methane Leaks from Natural Gas Systems

The 2020 report also provides estimates of methane emissions from leaks across Rhode Island’s natural gas distribution system. Methane is a potent greenhouse gas around 25 times more powerful than carbon dioxide. The inventory incorporates improved data from gas utilities on pipeline materials and leakage rates. This addresses a past reliance on limited EPA data that underestimated state methane leaks.

In 2020, methane leaks from gas mains and services accounted for 0.26 MMTCO2e or 2.7% of total state emissions. Leakage has declined 19.4% since 1990 as utilities replace older leak-prone distribution pipes. However, gas systems still represent a major source of greenhouse gas emissions that must be further reduced to meet state climate goals. Improved methane data will help better target and evaluate efforts to reduce emissions from this sector.

Land Use Emissions and Sequestration

The inventory also tracks carbon sequestration from Rhode Island’s forests, fields, wetlands and other natural landscapes that absorb and store carbon. In 2020, land use changes resulted in the sequestration of 0.68 MMTCO2e, offsetting 7.4% of the state’s gross greenhouse gas emissions.

However, Rhode Island has seen its carbon sequestration capacity decline 15.7% since 1990 as forests and farmlands are converted to residential and commercial development. Preserving and expanding natural areas and forests will be an important natural climate solution for Rhode Island. Tree planting programs in urban areas and farms can also sequester additional carbon.

The Next 30 Years of Climate Action

The 2020 Greenhouse Gas Emissions Inventory provides a detailed look at Rhode Island’s emissions sources and trends over the past 30 years. While the COVID-19 pandemic created an anomalous drop in 2020 emissions, the state has made measurable progress in reducing emissions from its largest emitting sectors.

However, far deeper emissions cuts will be needed to reach the Act’s ultimate goal of net zero emissions by 2050. The transportation and heating sectors remain among the most challenging to decarbonize. Accelerating the adoption of electric vehicles, low-carbon alternative fuels, energy efficiency, and renewable heating sources will be essential to driving further reductions. Continued climate action and progress towards these goals will be tracked in each year’s RI emissions inventory.