Transforming the Appliance Market: Strategies for Lower-Emissions Heat and Hot Water

Comments Off on Transforming the Appliance Market: Strategies for Lower-Emissions Heat and Hot Water

If the video is not visible, please accept all cookies to enable the player.

Fossil-fueled appliances in buildings are a significant source of emissions, not only of greenhouse gases but also pollutants such as nitrogen oxides (NOx), which are responsible for a variety of air and water quality and health problems. A model rule recently developed and published by RAP proposes an approach to regulating NOx emissions from water heaters over time. The goal is to drive transformation of the market for these appliances, particularly through adoption of efficient electric heat pump models. Similar appliance emission rules are already in place for water heaters and furnaces in the Bay Area of California and elsewhere, and other agencies are likely to follow suit.

To make such a transformation smooth for households, new appliance technology must be affordable and accessible. In an interactive webinar, panelists from RAP, RMI, Northeast States for Coordinated Air Use Management and the Vermont Energy Investment Corporation discussed the keys to transforming this market, from innovative appliance standards to consumer-friendly pilot programs.

Transforming the Appliance Market: Strategies for Lower-Emissions Heat and Hot Water

Comments Off on Transforming the Appliance Market: Strategies for Lower-Emissions Heat and Hot Water

Fossil-fueled appliances in buildings are a significant source of emissions, not only of greenhouse gases but also pollutants such as nitrogen oxides (NOx), which are responsible for a variety of air and water quality and health problems. In a webinar presentation, panelists from RAP, RMI, Northeast States for Coordinated Air Use Management and the Vermont Energy Investment Corporation discussed ways to drive transformation of the appliance market to reduce emissions.

NOx Standards for Water Heaters: Model Rule Technical Support Document

Comments Off on NOx Standards for Water Heaters: Model Rule Technical Support Document

RAP developed a model rule for use by U.S. state and local air quality regulators to reduce nitrogen oxide (NOx) emissions from water heaters. This technical support document was published to assist regulators and staff in understanding and making use of the model rule. It describes why water heaters are a significant source of air pollution, why NOx emissions standards are an excellent tool for reducing the environmental impact of water heaters and how those standards can promote electrification and market transformation. It also explains in detail the design and structure of the model rule.

Model Rule: NOx Standards for Water Heaters

Comments Off on Model Rule: NOx Standards for Water Heaters

Fossil-fueled water heaters represent a significant uncontrolled source of nitrogen oxide (NOx) emissions, which have a variety of harmful environmental effects. RAP developed a model rule for use by U.S. state and local air quality regulators to reduce NOx emissions from water heaters over time. A related technical support document explains the background and context of this work and describes in detail how the model rule was designed.

NOx, NOx — Who’s There? Decarbonizing Buildings Through Nitrogen Oxides Emissions Standards

Comments Off on NOx, NOx — Who’s There? Decarbonizing Buildings Through Nitrogen Oxides Emissions Standards

This fact sheet, prepared as a poster for presentation at the ACEEE 2022 Summer Study on Energy Efficiency in Buildings, describes the concept of a model rule to reduce emissions of nitrogen oxides (NOx) from fossil fuel-fired water heaters, an opportunity to transform the market for these appliances by driving the adoption of cleaner, more energy-efficient electric heat pump models.

Environmental Regulations and the “No Regrets” Approach: A Refresher for Utility Generators

Comments Off on Environmental Regulations and the “No Regrets” Approach: A Refresher for Utility Generators

Many of us have a hard time keeping track of where our federal government stands on environmental issues, especially when viewed through a political lens or from the perspective of the popular press. For example, in 2016 we signed on to the Paris Climate Accord. We withdrew in 2020, then rejoined in 2021. The Obama administration put in place numerous environmental regulatory programs. Subsequently, the Trump administration undermined them in court and dismantled them administratively. Then, rather than supporting the Obama administration’s Clean Power Plan, which was replaced by the Trump administration’s Affordable Clean Energy rule, the Biden administration took a different tack through a series of executive orders.

Despite being confusing at times, policy changes should not be an impediment to utility companies. The reason: Electric utilities across the country have always been masters of long-term planning. They know that major infrastructure projects take a long time — up to a decade or more — to conceive, plan and execute. More than half of all states require utilities to develop long-term integrated resource plans, a full range of feasible options on the supply side (utility-scale generation), demand side (customer-sited solutions) and distribution side (customer and community resources), and to assess them against a common set of planning objectives and criteria to meet expected customer service requirements into the future at least cost.

The truth is that utilities routinely make and execute resource plans, whether mandated or not. As illustrated in a blog one of us wrote in 2015, a careful assessment of risk factors will reveal that, in addition to what is immediately before you, utilities face “a host of other rules, initiatives, and market trends that are forcing other changes.”

So, instead of getting caught up in the latest pronouncements, utilities should make sure that they consider a wide range of regulatory scenarios, then develop plans to help them acquire a portfolio of resources capable of serving customers well, given existing trends and the law. In other words, “no regrets” approaches today can dictate what reasonably appear to be a company’s most equitable and economical choices.

What follows are some examples to illustrate that new environmental requirements could arise from federal laws already on the books. Utilities, working with their state regulators and stakeholders, should recognize and make long-term plans for these likely requirements.

Ambient Air Quality Standards (standards reviewed every five years)

The Clean Air Act requires the U.S. Environmental Protection Agency (EPA) to review the National Ambient Air Quality Standards every five years. This requirement includes primary and secondary standards for six of the most common air pollutants, known as criteria pollutants: carbon monoxide, lead, ground-level ozone, particulate matter, nitrogen dioxide, and sulfur dioxide. The purpose of the review is to ensure that these standards reflect the best, current scientific information to ensure the protection of public health and the environment.

These reviews depend on the development and evaluation of scientific information by the EPA, and, in turn, advice from the agency’s independent Clean Air Scientific Advisory Committee. Today’s utility planners should note the ongoing review of the air quality standards for fine particulate matter, for example. A 2021 Advisory Committee report indicates that the current standards may not be adequate to protect public health and welfare, as required. Particulate matter is emitted whenever fossil fuels are burned, so a tighter standard could result in more restrictions on processes and equipment (including power plants) that burn fossil fuels.

Section 110(a)(1) of the Clean Air Act requires states to submit State Implementation Plans to the EPA within three years after the initial development or revision of a national primary ambient air quality standard. State plans provide for the implementation, maintenance and enforcement of these standards.  These plans provide an excellent opportunity for utility regulators, utilities and community groups to help states design appropriate plans, consistent with other utility planning efforts.

Interstate Air Pollution (allowable emissions in 12 states are due to decrease through 2024)

In 2011, EPA finalized the Cross-State Air Pollution Rule (CSAPR) to address the emissions of criteria air pollutants that are transported across state lines and affect air quality in downwind states.

Because the interstate transport of emissions affects air quality and public health locally, regionally, and in states hundreds of miles downwind, this rule requires certain states in the eastern half of the United States to regulate and reduce power plant emissions to improve air quality. If a downwind state can demonstrate that upwind emitting sources in neighboring states are affecting its ability to comply with national standards, the “good neighbor” provisions of Section 126 of the Clean Air Act require the upwind source to either cease operation or comply with emissions limitations established by the EPA.

If the EPA determines that states are taking too long to implement changes to their state plans, the agency has the authority to issue a Federal Implementation Plan. In 2021, it issued new or amended plans for these 12 states, revising their emission budgets until air quality projections demonstrate resolution of the link between emissions in these states, allowing downwind states to meet air quality standards.

New Source Performance Standards for GHG Emissions (standards could be revisited any time)

In 2015, using authority from Section 111(b) of the Clean Air Act, the EPA set New Source Performance Standards for greenhouse gas (GHG) emissions from new, modified, and reconstructed fossil fuel-fired power plants. As required, the agency established these emissions standards based on its evaluation of the “best system of emission reduction” for affected sources. For example, the best system for baseload natural gas-fired turbines was determined to be the use of efficient natural gas combined cycle technology. For peaking turbines, however, the EPA determined that using “clean fuels” was the best system of emissions reduction. In neither case did the agency require new gas-fired turbines to match the performance of the lowest-emitting commercially available turbines.

In December 2018, EPA proposed revisions to the new source performance standards for coal-fired electric power plants relaxing the requirements. The primary reason given by the agency, “high costs and limited geographic availability of [carbon capture and storage] CCS.” Using the same authority, the EPA could likewise propose to tighten the standards for baseload and peaking gas plants. If it were to consider current resource information, the agency could revisit its best system of emissions reduction determination for a gas “peaker” and determine, for example, that new plants should not emit more than the very lowest emitting units on the market today.

Hazardous Pollutants (standard reviewed every eight years)

In 2012, the EPA developed the Mercury and Air Toxics Standard (MATS) pursuant to Section 112 of the Clean Air Act. That section gives the agency the authority to regulate hazardous air pollutants from stationary sources like electric generating units. Section 112 also requires periodic review and potential revision “taking into account developments in practices, processes, and control technologies.”

In fact, fossil-fueled electric power plants emit toxic air pollutants and could become subject to further restrictions given the EPA’s recent announcement about the need to enforce the mercury requirements, reversing another decision made during the Trump administration. The agency is taking comments on whether the mercury emissions limits should be made more stringent.

Utilities have the capability and the responsibility to factor all these contingencies and scenarios into their long-term plans and investment decisions. In the foreword to its 2011 publication Preparing for EPA Regulations:  Working to Ensure Reliable and Affordable Environmental Compliance, RAP quoted Moody’s Investor Service:

 …credit risk factors associated with energy and climate legislation have existed for decades and managing these risks are considered a core competency for all utility operators, whether they are regulated or un-regulated, public, or privately-owned.

This applies as much today as it did 10 years ago when Moody’s made the pronouncement. Staying abreast of changes to environmental and public health laws and their potential effects on the utility sector continues to be an important responsibility of utility owners, operators, and regulators.

How Electrifying Trucks Can Help Roadside Neighborhoods Breathe Easier

Comments Off on How Electrifying Trucks Can Help Roadside Neighborhoods Breathe Easier

We know that electrifying trucks, as we wrote last month, can reduce significant amounts of air pollution; it can also have significant health benefits, particularly for frontline communities. Analysis by Alexander Meitiv and Ann Xu for Texas A&M’s Transportation Institute finds that, by electrifying just 40% of existing, predominantly diesel-fueled medium-and heavy-duty vehicles in the eight-county Houston area, Texans could avoid more than 21 tons of nitrogen oxides (NOx) – over a quarter of the 80 tons a day emitted per day by Greater Houston’s on-road traffic. This could be achieved by electrifying a little over 60,000 medium-and heavy-duty vehicles, about 1% of all the vehicles in greater Houston.

This is big news for all areas in non-attainment for ozone under the Clean Air Act, a serious public health and economic challenge. But it is especially big news for people living near highway corridors, because electrifying the same vehicles also reduces fine particle emissions by nearly 20%.

Fine Particulates Are Deadly

Tailpipe emissions from medium- and heavy-duty diesel trucks contain significant amounts of fine particle pollution, also referred to as “PM2.5.” PM2.5 are particles that are 2.5 microns or smaller that are produced along with partially combusted fuel and from other pollutants like nitrogen and sulfur oxides. (To get a sense of just how small 2.5 microns is, the diameter of a human hair is around 50 microns.)

The World Health Organization’s International Agency for Research on Cancer characterizes PM2.5 as a carcinogen, and for decades, we have known that PM2.5 causes premature mortality. In the proceedings of the National Academy of Sciences research indicates that roughly 100,000 Americans per year die from fine particle pollution.

In spring 2020, public health researchers at Harvard issued a study further illustrating the danger of particulate pollution. They found that the pre-existing conditions that increase the risk of death in those with COVID-19 are the same diseases that are affected by long-term exposure to air pollution, and that a small increase in exposure to PM2.5 leads to a large increase in the COVID-19 death rate. Emissions from medium- and heavy-duty vehicles, a major source of PM2.5, should be of grave concern and raise a red flag.

Who Is Affected?

Low- and moderate-income (LMI) communities and communities of color, especially those located near transportation corridors, are disproportionately affected by transportation-related emissions of PM2.5. Meitiv and Xu’s analysis finds that the proximity and exposure to truck-related emissions in certain neighborhoods “leads to environmental justice questions related to air pollution and public health.”

LMI communities are often located in very close proximity to roadways because property values in those areas are likely to be lower . The CDC has found that racial and ethnic minority communities, foreign-born people, and people who speak a language other than English at home represent the highest percentage of people living within 500 feet of a major highway.

As illustrated in the following figures, people living in close proximity to roadways in the Houston-Galveston region are subject to long–term exposure to these pollutants. Figure 1 shows a census block map organized by percentage of low- and moderate-income (LMI) residents. As the legend suggests, the darker the shade, the higher the percentage of LMI residents in each block.

Figure 1: Census Block Group Map of Percentage of LMI Residents

Figure 1 shows that in Houston’s surrounding communities – the northwest, northeast and southeast quadrants – neighborhoods are home to 50–100% LMI residents. Even in the city’s southwestern suburbs (lighter shade), where the relative percentage of LMI residents is low, there are still neighborhoods where the proportion ranges between 20% to as much as 50%.

The Strategy: Electrify Medium- and Heavy-Duty Vehicles

The most effective way to improve air quality for communities near roadways, according to the EPA, is to “reduce the emissions of each vehicle on the road and the number of vehicle miles driven.” Vehicle electrification can reduce emissions. And Meitiv and Xu’s research illustrates how the electrification of medium- and heavy-duty vehicles can be especially effective.

Figure 2: PM2.5 Concentration Reduction From 40% Heavy-Duty Truck Electrification

In their analysis, the authors found that (1) heavy-duty long-haul electrification reduces emissions along major corridors, whereas (2) medium-duty short-haul electrification reduces emissions across secondary roadways, especially on the west side of Houston. Figure 2 illustrates reductions of PM2.5 concentrations (the lighter colors) across Houston and the surrounding areas produced by the electrification of 40% of heavy-duty trucks in the region. In addition, emissions reductions from electrifying heavy-duty trucks can be seen along major corridors in the region, including routes to Galveston to the southeast, Lake Jackson to the south, and Bay City to the southwest.

Figure 3 illustrates reductions of PM2.5 concentrations (the lighter colors) produced by the electrification of 40% of medium-duty trucks in the region. Most notable are PM2.5 emissions reductions in the areas to the west and the northwest of Houston, on secondary roads and, similar to the effects produced by electrifying heavy-duty trucks, on major corridors as well.

Figure 3: PM2.5 Concentration Reduction From 40% Medium-Duty Truck Electrification


Electrifying trucks can reduce air pollution significantly and produce public health benefits, particularly for frontline communities. Texas A&M Transportation Institute’s analysis identifies major benefits in NOx reductions by electrifying a fraction of diesel-fueled vehicles on Houston’s highways. They also found an important co-benefit of the same truck electrification strategy: Electrification reduces deadly PM2.5 emissions by 20%. Not only is this good news for overburdened Houston neighborhoods near roadways, but it also has positive implications for similar communities throughout the United States.