MONITORING, MODELING, AND MANAGING GREENHOUSE GAS EMISSIONS

The 2019 greenhouse gas (GHG) emissions inventory prepared by the Nevada Division of Environmental Protection (NDEP) under NRS 445B.380 provides an informative assessment of current statewide GHG emissions and is a helpful starting point for identifying the major sectors expected to drive future GHG emissions in Nevada.

In order to support a comprehensive and consistent evaluation of GHG emissions-reduction benefits from policies across the state, Nevada’s inventory capabilities would need to expand.

In order to support a comprehensive and consistent evaluation of GHG emissions-reduction benefits from policies across the state, Nevada’s inventory capabilities would need to expand. This includes: 

  • access to input data that are current and specific to Nevada by emissions sector, locality, and individual policy; and
  • an integrated GHG inventory framework that:
    • includes algorithms reflecting the interconnected nature of policies across sectors, jurisdictions, and time scales, and
    • synchronizes with existing processes, analyses, and resources used for local and regional development, land use, and transportation planning.

CURRENT NEVADA EMISSIONS INVENTORY EFFORTS

Several state, regional, and local agencies, as well as larger private entities, are engaged in GHG emissions inventory efforts to meet a range of objectives.

Several state, regional, and local agencies, as well as larger private entities, are engaged in GHG emissions inventory efforts to meet a range of objectives. The GHG Inventory Working Group reached out to numerous entities to assess the current practice of emissions inventory efforts statewide and to understand how these efforts may support or complement the State Climate Strategy and the broader goals of the State of Nevada Climate Initiative (NCI).

The GHG Inventory Working Group convened a series of group and individual discussions in August, September, and October 2020 with representatives from the following organizations to assess current efforts and plans for GHG inventories in Nevada. These discussions were intended to develop mutual understanding of the scope of each entity’s emissions tracking and platform, as well as to learn more about opportunities and impediments to GHG emissions reporting that could complement and inform NDEP’s statewide reporting:

  • City of Henderson
  • City of Las Vegas
  • City of Reno
  • Clark County School District (CCSD)
  • Clark County Department of Environment and Sustainability
  • Clark County Department of Aviation (CCDOA)
  • Nevada Department of Transportation (NDOT)
  • Regional Transportation Commission of Washoe County (RTC Washoe)
  • Southern Nevada Regional Transportation Commission (RTCSNV)
  • Tahoe Regional Planning Agency (TRPA)
  • Washoe County Air Quality Management Division
  • Washoe County School District (WCSD)

GHG emissions inventory efforts are not mandated by state law, or local codes or ordinances, but completed at the discretion of local governing bodies within individual resolutions or as part of master plan documents.

Inventory efforts currently conducted and planned within Nevada fall into three categories:

  • Jurisdiction-wide or “community-scale” inventories that include GHG emissions for all sectors and all sources generated within a certain jurisdiction (e.g., state, county, or city);
  • Regional transportation-sector inventories associated with the transportation sector for designated metropolitan planning areas (MPAs); and
  • Operations inventories, which are typically self-assessments of an individual organization’s direct (and in a smaller number of cases, indirect or value-chain) GHG emissions.

Jurisdiction-Wide Inventories

As required by NRS 445B.380, NDEP has produced four GHG inventories (published in 2008, 2012, 2016, and 2019). NDEP uses the U.S. EPA State Inventory Tool and U.S. Energy Information Administration Annual Energy Outlook. This is supplemented with available Nevada-specific electricity generation projections, Nevada state demographer population projections, and modifications to conform to updated Intergovernmental Panel on Climate Change (IPCC) pollutant global warming potentials. Because of how data flows and is processed through the EPA State Inventory Tool, NDEP inventories have been approximately three years behind. For example, the 2019 inventory calculates emissions based on 2016 data. For 2017 through 2039, the NDEP inventory projects statewide GHG emissions by emissions sector through 2039, with projections starting from 2016 emissions data as the baseline inventory.

Some of the larger municipalities in Nevada, including Reno (2014) and Las Vegas (2020), have completed jurisdiction-wide GHG emissions inventories. In 2011, the Washoe County Air Quality Management Division completed a community-scale GHG inventory for Washoe County. Following up on previous GHG inventory efforts by the Southern Nevada Regional Planning Coalition in 2017, the Clark County Department of Environment and Sustainability is currently scoping a county-wide GHG inventory effort.

However, NRS 278.160 does not require GHG emissions inventories be included in community master plans. NRS 278.160(2) allows local jurisdictions to prepare and adopt, as part of their master plans, additional planning and reports that in the judgment of that local authority’s governing body relates to the physical development of the local jurisdiction. This may include GHG emissions inventories and projections. These GHG emissions inventory efforts are not mandated by state law, or local codes or ordinances, but completed at the discretion of local governing bodies within individual resolutions or as part of master plan documents.

The most recent Reno, Washoe County, and Las Vegas GHG emissions inventories do not contain projections. The Las Vegas Draft 2050 Master Plan indicates it will prepare GHG emissions projections going forward. Las Vegas also includes in its draft 2050 Master Plan the goal of completing annual GHG emissions inventories. Reno’s 2017–2036 master plan, Reimagine Reno, incorporates by reference the goal from its 2019–2035 Sustainability and Climate Action Plan to complete GHG inventories on a three-year cycle.

A key difference between the NDEP inventory, which is mandated by state statute, and local jurisdiction inventories is how electricity generation emissions are segregated from residential/commercial and industrial emissions. In the NDEP inventory, these three sectors are tracked individually. In the local jurisdiction inventories, electricity generation is a subset of residential, commercial, and industrial sector emissions rather than a separate sector. These are the types of baseline differences that need to be accounted for to compare GHG emissions-reduction impacts of policies that may be implemented locally, regionally, and statewide. Further review is needed to understand what portion of electricity generation accounted for within the local emissions inventories may originate from electricity generated outside of the state. For the NDEP inventory, only GHG emissions from electricity generation within state boundaries is included in emissions calculations. Since Nevada-based power plants generate most of the electricity consumed in the state, this is not expected to have a significant impact.

Regional Transportation-Sector Inventories

Federally-designated metropolitan planning organizations (MPOs)—including RTCSNV, RTC Washoe, TRPA, and others—complete regional transportation plans at least every four years as required by federal regulations (23 CFR Part 450). As part of developing these plans, MPOs analyze alternatives against a number of criteria, including air quality projections. These regional transportation plans project MPA-wide air emissions for Clean Air Act criteria pollutants. This information is also incorporated into air quality planning documents required by the Clean Air Act by local agencies in Washoe and Clark County. Except for TRPA, these emissions estimates do not currently include GHG emissions projections.

Because TRPA is an MPO partially located in California, it is required under California statutes (2008 CA SB 375) to coordinate both transportation and land-use planning to evaluate and reduce GHG emissions. TRPA completed a 2017 Linking Tahoe: Regional Transportation Plan that integrates land-use planning and transportation demand scenarios into GHG emissions projections. The TRPA has released a draft 2020 transportation plan that includes these same elements.

NDEP statewide GHG emissions inventory estimates for the transportation sector are based on statewide fuel consumption data and estimated combustion efficiency. There are also default assumptions regarding vehicle miles traveled and assumed vehicle age distribution contained within the EPA State Inventory Tool. Moving towards transportation-sector GHG emissions projections, this high-level, coarse calculation cannot account for different long-term transportation and land-use development patterns resulting from different local and regional policies and scenarios.

Operations Inventories

Several organizations (e.g., RTCs, CCSD, WCSD, cities, CCDOA), including several private entities (and in 2020, NDOT), have completed GHG emissions inventories of agency operations. These include assessments of GHG Protocol Scope 1 (direct emissions associated with burning fossil fuels, such as natural gas for space heating and hot water or gasoline and diesel for internal combustion engine cars ), Scope 2 (indirect emissions associated with purchased energy, especially for electricity consumption ), and in limited cases Scope 3 (emissions associated with upstream and downstream supply-chain) emissions sources.

Platforms and reporting mechanisms used include those provided by the Carbon Footprint Registry (formerly the Climate Registry), Carbon Disclosure Project (CDP), Global Protocol for Community-Scale Greenhouse Gas Emission Inventories (GPC), and the EPA Simplified GHG Emissions Calculator.

These detailed, bottom-up inventories are very important to understand the carbon footprint of individual government agencies and individual entity operations. They provide the underlying basis for illustrating and defining “lead-by-example” practices and help to identify opportunities for improvements in efficiency, cost-savings, and procurement policies that can reduce GHG emissions. However, these inventories are limited in their potential to contribute to statewide inventories across all sectors or for understanding the relative impact of policies across sectors and jurisdictions.

Detailed, bottom-up inventories are very important to understand the carbon footprint of individual government agencies and individual entity operations. However, these inventories are limited in their potential to contribute to statewide inventories across all sectors or for understanding the relative impact of policies across sectors and jurisdictions.

GHG DATA NEEDS IDENTIFIED BY 2019 NDEP GHG EMISSIONS INVENTORY

Section 11 of the 2019 NDEP GHG inventory identifies several data needs that would help to ensure the statewide inventory is complete and up to date. For example, a qualitative assessment of the ability of identified policies to support long-term goals of net-zero GHG emissions by 2050 could not be performed due to lack of data.

In the 2019 inventory, NDEP specifically identified the need to further research available knowledge and state of the practice related to carbon sequestration on Nevada rangelands. Among the uncertainties in the NDEP GHG emissions inventory, these data could have a significant effect on estimates of net GHG emissions from the state both now and in the future. A description of that effort is under way as further described in Box 1.

Box 1. Natural and Working Lands Carbon Sequestration Project

Effective carbon sequestration, or carbon storage, is a key element in reducing GHG emissions in the environment—and fostering healthy natural ecosystems is necessary to this process. The Nature Conservancy, together with the Nevada Division of Natural Heritage, is working on a project to model the estimated amount of net carbon stored per acre through transforming non-native grasslands to native vegetation and evaluate the estimated cost of storing net carbon through the native grassland restoration process.

The proposed project aligns with the policies outlined in NDEP’s 2019 GHG emissions inventory, including:

  • Promote land management practices that increase carbon sequestration by natural lands that are typical and/or native to Nevada.
  • Expand specific programs to restore and enhance habitats with measurable carbon sequestration co-benefits.
  • Promote land management practices that decrease the risk of catastrophic wildfires.

Calculating the net carbon storage and cost of restoration of Nevada’s grasslands provides several additional benefits. Enhancing carbon sequestration below ground in rangeland soils serves as a more-stable carbon sink compared to forests, where the majority of carbon sequestration occurs in the trees, which can then burn, be logged, or be developed. Restoring grasslands reduces wildfire frequency and is less expensive than other rangeland restoration practices. This process provides additional benefits as well, including enhancing habitat for Greater Sage-Grouse and insect pollinators. Additionally, we would see an increase in the quality of forage for herbivores and livestock.

GHG DATA NEEDS IDENTIFIED BY CLIMATE MITIGATION POLICY EVALUATIONS

The individual evaluations of climate mitigation policies illuminated additional data needs. In many cases, the impact of a policy, program, or regulation on GHG emissions could not be estimated because of a lack of data. 

The underlying factor that affects GHG emissions projections for many policies is the percent of electricity consumed in Nevada that comes from renewable sources. Nevada’s current statutory requirement to achieve a 50% renewable portfolio standard by 2030 will impact the GHG emissions-reduction effectiveness of policies across sectors.

The individual evaluations of climate mitigation policies illuminated additional data needs. In many cases, the impact of a policy, program, or regulation on GHG emissions could not be estimated because of a lack of data.

For example, policies that increase electrical efficiency of appliances and buildings, or increase the relative percentage of electric vehicles compared to internal combustion engine vehicles on the road, will result in different levels of GHG emissions reductions depending on the percentage of Nevada’s electricity that comes from renewable sources.

For policies that may be implemented on a local or regional level, additional information on the percentage of renewable energy supplied to individual areas of the state and effects of the wholesale energy market on these areas would be needed. In many cases, it may be more appropriate to provide a range of GHG emissions-reduction projections for a given policy to account for uncertainties, rather than a single point estimate.

FRAMEWORK FOR FUTURE STATEWIDE GHG INVENTORY EFFORTS 

After discussions with organizations and stakeholders across Nevada, the state could benefit from an integrated statewide GHG emissions inventory framework. There are multiple items that must be considered in developing a framework for a comprehensive, statewide GHG emissions inventory. 

  • Operations inventories focused on individual entity emissions impacts will be helpful to identify “lead-by-example” areas for government and private-sector GHG emissions reductions, but will likely remain difficult to integrate and separate from the statewide inventory. These efforts may be summarized in a separate lead-by-example compilation of operations inventories if they are reported in a consistent format.
  • Estimates of cumulative statewide GHG impacts of land use, development, and regional transportation policies in the statewide inventory may benefit from regional and local planning efforts (e.g., master plans and regional transportation plans) that incorporate GHG emissions inventories and projections.
  • Regional and local planning efforts that incorporate GHG emissions inventories and projections would need to incorporate consistent format, methodology, and accounting for comparisons across jurisdictions and sectors.
  • The statewide framework for projections could be adapted to synchronize with regional and local planning cycles (e.g., master plans and regional transportation plans) thereby taking advantage of existing planning resources and local planning expertise and knowledge.
  • All governmental entities expressed a strong interest in continued interagency collaboration on consistent GHG inventory practices but noted that available resources for GHG inventory efforts are very limited. The statewide framework will benefit from ongoing collaboration such as regular meetings and updates from agencies. This can include introduction of opportunities and platforms to help integrate complementary GHG emissions reporting across jurisdiction and for the state to remain engaged with and connected to local and regional efforts.

The World Resources Institute has developed a comprehensive Policy and Action Standard that provides a standardized framework for estimating and reporting the change in GHG emissions and removals resulting from policies and actions. Together with an inventory platform, adaptation of this standard (or another systematic framework), could help to integrate consistent GHG emissions-reduction analysis of policies across planning organizations.

The state could benefit from an integrated statewide GHG emissions inventory framework.

The GHG Inventory Working Group performed an initial survey of available inventory platforms that can perform integrated, modular, and interactive cross-sector and potentially cross-jurisdiction GHG emissions-projection analysis of individual and related policies. Either these or other platforms will require further evaluation of cost and identification of additional resources to use effectively. The examples below may warrant further consideration based upon a preliminary evaluation of the parameters of each tool’s modeling capabilities, ease of use, extent of adoption, and the cost of the platforms:

  • Open-Source Energy Policy Simulator (EPS) developed by Energy Innovation: Policy and Technology LLC (https://us.energypolicy.solutions/
    • This open-source computer model is designed to inform policymakers and regulators about climate and energy policies, individually or as a package, that will most-effectively reduce GHG emissions. EPS can model the economic sectors required to be analyzed in the NDEP annual report, and includes outputs such as job impacts, cash flow, multiple pollutants, and public health.
  • Low Emissions Analysis Platform (LEAP) developed by the Stockholm Environment Institute (https://leap.sei.org/
    • LEAP is a software tool for creating quantitative modeling of energy systems, pollutant emissions from energy and non-energy sources, and costs and benefits and related externalities. It has been used in multiple states and as the basis for many countries to meet their commitments to the Paris Agreement. Licensing and training can be low-cost, but customized modeling would require more-significant investment.