The Sensor Surge: Why Equipment Engineers Are Adding Sensors Everywhere — and Why the Wood Stove May be Next

MF Fire is the US industry leader in
integrating sensors into wood stoves

Over the last decade equipment engineers have been rapidly adding sensors to cars, HVAC systems, laundry machines, refrigerators and other household appliances. That trend isn’t just about bells and whistles — it’s driven by lower sensor costs, smarter processing at the edge, connectivity, regulatory and efficiency pressures, and real customer value. Below is a concise look at the benefits, the sensor types being deployed, why prices are falling, where the trend is headed, and how this sensor wave will likely soon be more widespread in something old-school: the wood stove.

Sensors have slowly started to enter the wood stove technology space and are catching on in Europe much faster than North America.  In the US, the Baltimore-based MF Fire made an after-market device with funding from the Department of Energy that represents the most sophisticated use of sensors for wood stoves.  At least one big European stove brand, Jotul, with a major footprint in the U.S. are releasing stoves with automated combustion control only in the European market. 

In 2025, Ecodesign suggested that automated combustion control (ACC) should become mandatory on all new stoves, a suggestion that presumably comes from studying the Blauer Engel (Blauer Engel, 2020) certification. This sent a kind of a shockwave through the stove manufacturing industry, and resulted in industry pushback.  The Nordic Ecolabelling system, representing five countries, is considering requiring ACC in new stoves, or other technology innovation. 

According to a 2025 report from Nordic Energy Research, "In Europe, fully automated stoves have been on the market for some time—for example, RIKA (AU) since 2007 (RIKA Rikatronic, 2025) and HWAM (DK) since 2012 (HWAM, 2025)—and are beginning to gain wider recognition amongst consumers and distributors. The Rikatronic technology (now Rikatronic4 as the latest version) was introduced by RIKA of Austria in 2007; it integrates temperature sensors and electronics to control the air supply and advises when another wood log should be put on the fire through a light visible at the front of the fireplace. This seems to be the most advanced technology for a batch fed or manual wood log burner in terms of automating the reloading and ensuring optimum firebox temperatures for reducing emissions."

There are now more than 10 wood stoves with ACC on the market in Europe, with many in the range of US$2,500 - $4,000.  The best selling automated stove in the world may be the Connect 556 made by Contura a major Swedish stove manufacturer.  Once wood stove certification tests become stricter than they are today in the US and Europe, automation is likely to be the safest way to pass the tests.  Otherwise, the inherent variability in combustion in manually operated stoves will not leave any comfortable margin to passing emission tests.  Currently, stove certification labs on both continents have been able to develop the expertise to pass emission tests without hardly any record of stoves failing the test.

European retailers are also starting to advertise the benefits of automated stoves, socializing the technology benefits to consumers, retailers and the wider community concerned about the health impacts of residential wood smoke. But wood stoves still lag far behind other heating and combustion devices when it comes to embracing the adoption of more and more sensors.

It is important to distinguish full automation in wood stoves from partial automation. Full automation means that the stove has no lever for the operator to adjust air flow, unless the onboard computers can override and optimize the stove for emissions, before responding to the user adjustment for more or less heat. With partial automation, the stove still has a lever or handle to adjust airflow, and the stove has some technology to make minor adjustments in air flow.  The bi-metal coils in Blaze King stoves could be considered partial automation, along with the valves in Pacific Energy Neo stoves. Partial automation, often achieved with the need for electricity, appears to only offer minor benefits compared to fully automated stoves.

Without automation, there is
virtually no way to predict the
performance of a stove 
once it leaves the lab.

Air quality agencies in the U.S. – from the EPA, to NESCAUM to state and local agencies – have been focusing on the shortcomings of the certification process and on designing a better testing protocol.  But US institutions are far behind Europe in studying and promoting automation in stoves.

One of the most obvious benefits of ACC is to prevent overnight smoldering along with speeding up the start-up of the stove. But it may be the safety aspects – producing less creosote and safety sensors that offer peace of mind to homeowners (and insurance companies) that will drive innovation.

From 2013 – 2023, the Alliance for Green Heat ran a series of Design Challenges with the Brookhaven National Lab, and funding from NYSERDA, the Department of Energy and Osprey Foundation that sought to accelerate research and production of automation in wood stoves. Some of the contestants, such as MF Fire, have gone on to get that technology into the marketplace with the Fire MAPS Smart Fire Assistant. 

Why sensors are being added:

• Improved safety: early detection of hazards (overheat, leaks, CO) reduces fire and poisoning risk.
• Energy efficiency and emissions: feedback lets systems run only as hard as needed (modulating burners, variable fans).
• Predictive maintenance: sensors spot component wear and anomalies before failure, lowering downtime and service costs.
• Better user experience: remote monitoring, diagnostics, adaptive settings, and automated schedules.
• Regulatory and reporting needs: emissions, indoor-air-quality (IAQ) monitoring, and energy reporting demand measurement.
• Data-driven product improvement and new services (e.g., subscription performance monitoring).

The use and benefits of sensors are different for each
application based on the risks that application faces.

Common sensor types now used in consumer equipment

• Temperature sensors (thermistors, RTDs, digital temp ICs) — ubiquitous in HVAC and appliances.
• Pressure sensors — used for refrigerant systems, combustion chambers, and airflow measurement.
• Humidity sensors — for IAQ, laundry cycles, and HVAC control.
• Gas sensors (CO, CO2, O2, NOx) — safety and emissions control in furnaces and cookers.
• Particulate sensors (optical/laser) — measuring PM2.5/PM10 for IAQ and emission controls.
• Flow sensors (air and liquid) — ensure correct ventilation, fuel, and coolant flow.
• Vibration and accelerometers — detect mechanical faults in compressors, pumps, motors.
• Current and voltage sensors — monitor electrical health and detect stalled motors or short circuits.
• Optical and camera sensors — visual inspections, flame detection, and product state recognition.
• Position and angle sensors — actuators, dampers, and valve control.

The steady growth in the use of sensors is driven by
safety, consumer appeal and benefits to manufacturers. 

Why sensor prices are falling

• MEMS and semiconductor scaling: MEMS fabrication and CMOS integration drive down unit cost and size.
• High-volume consumer markets: smartphones, wearables, and automotive volumes subsidize production for other markets.
• Integration: multifunction sensor packages combine temperature, pressure, humidity, and motion on a single die, lowering BOM cost.
• Standardization and modularity: off-the-shelf sensor modules and cloud-friendly firmware speed integration and reduce engineering cost.
• Wireless and low-power tech: cheaper connectivity (BLE, LoRaWAN, Thread) reduces installation complexity and cost of retrofits.

Is the trend likely to continue? Yes. Expected drivers:

• Continued unit-cost declines and richer sensor fusion capabilities.
• Edge computing and tiny ML: more intelligence on-device reduces data bandwidth and privacy concerns.
• Stricter efficiency and emissions standards worldwide.
• Growing consumer demand for smart, connected products and services.
• OEMs monetizing data and offering remote service/subscription models.

Expect more sensors per device, tighter integration with controls, and better diagnostics.

HVAC sensors are dominated by temperature sensors, which 
in wood stoves are usually Type K thermocouples that 
typically cost a dollar or two.

Is this trend likely to come to wood stoves? Yes — and in multiple practical ways:

The increased use of sensors in stoves is likely for many reasons, not least of which is that they should make it easier to pass new certification tests in the US and Europe. Automation directly address the IDC’s challenge of consistent, repeatable combustion across varied loads and user behavior. That could make automation an attractive technical route to meet performance targets reliably. However, many manufacturer don't have experience with sensors and will likely want to optimize passive design, secondary combustion, or catalytic systems rather than add electronics.

The biggest hurdle in the short term is that government regulators in the US and European countries often do not have the expertise, resources or clout to overcome resistance by industry to changes leading to improved test methods and stricter emission limits. The US currently has an industry friendly, anti-regulatory administration, which could mean individual states get more involved.

Politics aside, the sensor boom is applicable in wood stoves in obvious ways:

• Combustion efficiency: O2, CO, and temperature sensors can enable feedback-controlled air supplies to keep burn in the optimal stoichiometric window, increasing heat output and reducing fuel use.
• Emissions reduction: particulate sensors (optical) and CO monitors can detect smoldering or incomplete combustion and trigger corrective measures (adjust draft or alert the user), reducing smoke and creosote formation.
• Safety: CO sensors and high-temp cutoffs can warn of dangerous conditions or auto-shutdown linked to ventilation failure.
• Draft and airflow control: pressure or differential-pressure sensors across the stove and flue help manage draft for steadier burns.
• Predictive maintenance: temperature profiles, and smoke signatures can indicate gasket wear, or creosote build-up.
• Remote monitoring and automation: smartphone alerts, remote adjustments to air dampers or blower speeds, and usage logging for fuel optimization.
  
  

  

  In the US, the Department of Energy is
  also supporting important automated 
  stove research at Nordica McCarthy's
  lab at Oregon State University

Practical considerations and challenges for wood stoves

Wood stoves present unique challenges because they use a solid fuel with very diverse characters, unlike electricity liquid fuels. In addition:

• Harsh environment: soot, ash, high temperatures and corrosive gases require rugged sensors and protective housings.
• Sensor placement: measuring combustion gases accurately often needs sampling ports or heated lines to the sensor; fouling is a risk.
• Power and connectivity: many stoves are off-grid or in remote cabins; low-power sensors and local edge logic are important. The ability of the stove to work without electricity/sensors is important.
• Cost vs. value: retrofit kits must be affordable and simple; OEM integration at manufacture yields better reliability.
• Certification and safety/regulatory acceptance: devices that influence combustion or safety need testing and standards compliance.
• User behavior: alerts are useful only if users understand and act on them; automation helps and users are learning from all the other sensor interactions in their daily lives.

Jotul says this stove "continually
monitors  temperature  and
automatically  adjusts  air supply  to
optimize combustion — giving cleaner,  more
efficient burning  and reduced emissions."

How this could be deployed

• OEM integration: manufacturers build sensors and control loops into new stoves (best performance and reliability).
• Retrofit modules: compact sensor packs (temp, CO, O2, particulate) with a local controller and optional wireless gateway for older stoves.
• Service-focused models: subscription diagnostics for stoves used in rentals, remote cabins, or commercial premises – or in any stove where the user wants greater peace of mind.
• Simple consumer features: auto-damper control, burn-stage alerts, and CO alarms tied to phone notifications.

Bottom line: Falling sensor costs, smarter edge processing and connectivity are driving a widespread sensor adoption in vehicles and home equipment — and that momentum should continue. Wood stoves are a natural candidate for the next wave of sensor-driven improvements: safer, cleaner, and more efficient burning is technically feasible today, but practical rollout requires rugged sensors, thoughtful placement, simple user interfaces, and standards-compliant designs.

Innovation in stove technology will also be driven by public health concerns. If wood stoves continue to be popular or become more so due to rising heating fuels - electricity, gas and oil - there will likely be more pressure on governments to do a better job at certifying new stoves. However, global warming is making winters warmer, reducing heating bills, which typically reduces the use of wood stoves, which in turn may ease pressure on air regulators.

Demand for automation in wood stoves moves forward in Europe, but could be sidelined in the U.S.

Updated July 8, 2026 - The newest type of stove on the market is the automated or ‘smart’ stove that use sensors and computer chips to adjust airflow, instead of relying on the operator. Automated stoves enable the operator to "load and leave," allowing the stove to maximize efficiency and emissions reductions on its own. These stoves are likely to be the next major step towards cleaner residential wood heating because it is well-known that poor operation by the consumer is one of the main reasons for excessive smoke, and often it is the main reason. 

Automation does not just seek to address poor operation by the consumer.  It also can assess variable draft conditions caused by different chimney configuration, the altitude of the home, and the moisture content of the wood.  In addition, automated stoves are often interactive, helping to educate operators through visual prompts or detailed apps on smart phones. 

 

In Europe, automated stoves have been advancing far more quickly and are recognized as by the regulatory community as an important solution.  In the U.S., the EPA and other agencies are focusing on an equally important process - improving test methods for manually operated stoves – with little attention to automation. Improved test methods still leave manually operated stove vulnerable to wildly variable real-world emissions.  

 

Outside of regulatory circles, automated stove technologies have been promoted in the U.S. by the Wood Stove Design Challenge, a series of technology competitions, and by funding from the US Department of Energy in association with national labs.  A 2023 study from Brookhaven National Lab described the technology as “a minimal set of measurement sensors and a heuristic control strategy to actively modulate incoming air to enhance stove combustion performance, thereby eliminating user-error as a factor for emissions production.” More recently, researchers at Oregon State University and Aprovecho Research Center are focusing on automated technologies that show PM reductions up to 95% compared to older models

 

The first such stove on the US market, MF Fire’s Catalyst, launched in 2016, is now off the market. The second, Charnwood, a British manufacturer entered the US market in 2020 with their Skye E2700. The company say, “This stove uses Charnwood I-Blu combustion intelligence that continuously monitors the state of the fire and optimizes efficiency while reducing emissions through real-time adjustments. Air is introduced in just the right amounts, in the right places, at exactly the right time to ensure a cleaner, highly efficient burn.”

 

A number of companies are using passive, partial automation but its unclear how effective it it.  For example, Pacific Energy has added technology to three of their stove models. The Neo 1.6 LE2 and the larger NEO 2.5 LE2, both of which come in freestanding and insert models. Under their True North brand, the TN25 C, they use the same technology on a hybrid stove with a catalyst that is continuously engaged, and does not have a damper control. According to an email from Pacific Energy, they use an “algorithm controlling two sources of supplemental air, working in the background to seamlessly improve combustion.  This patent pending technology uses two probes to monitor the firebox and the flue temperatures. Based on the absolute, delta and the rate of change in temperatures, the combustion is being optimized at all times.”  The operator can still adjust the air damper, which may be then counteracted to some extent by the algorithm depending on combustion conditions. Pacific Energy markets these stoves as regular wood stoves without explaining the details of their automation to the consumer. 

 

The Canadian manufacturer SBI won an award at the 4th Wood Stove Design Challenge for their progress toward an automated stove and they received a grant from the DOE to develop it. A final version of it is expected to be EPA certified and on the North American market later in 2025. 
 
Automated stoves on the European market
In Europe there has been far more R&D and diversity of automated stove technology.  Notably, in Europe, manufacturers highlight the environmental benefits of automation to the public and to the regulatory community. There are now more than 10 models on the market such as: 

 

Hase, Lima IQ (Germany)

Hwam SmartControl (Denmark)

Nordica, Larissa (France)

Rika, Rikatronic4 (Austria)

Scan Zensoric Technology,  (Denmark)

Xeoos Twinfire Blue (Germany)

Wodtke, Stage F (Germany)

Full vs. partial automation.  There are many ways to automate a wood stove and one of the main variables is whether the stove still has air levers that the operator can control.  If the stove has controls for the operator, it is virtually impossible to tell if the automation can override the operator, or vice versa.  Many consumers, particularly in North America, want to at least have the sense that they can control air flow, which is key to heat output.  Otherwise, control of heat output can be with the amount and frequency of wood that is loaded into the stove. Also, there is always the question of whether and how well an automated stove works during a power outage.  Most, if not all, can work, but will do so sub-optimally. 

Bi-metal springs that have been used for decades in stoves produce a very modest amount of automation to stoves, and they can be used in conjunction with electronic automation strategies.  

Other features. Some stoves have a LED light that will come on when its time to reload the stove.  Some are connected via wi-fi apps and can produce a sound to prompt the consumer when to reload. The Austrian company Rika has a feature where you load firestarter in the tray, add wood, and then you can program the stove to start remotely, as pellet stoves can.

Aftermarket solutions. Several companies have built devices that can monitor and/or control the airflow of existing stoves or be integrated into new stoves.  Maxitrol is a leading supplier and makes the battery powered “E-Flame air control system” that drives an actuator to control primary and secondary air flow.  It was designed in part to help companies meet future European EcoDesign Directives.  The Danish stove manufacturer Aduro has had it’s Smart Response on the market for several years. The app-connected thermometer provides feedback to the consumer on their smart phone about whether their stove is burning well, and how to improve its use.  Baltimore-based MF Fire is working on something similar. These technologies do not automate stove functions but monitor conditions and prompt the user to give the stove more air, add wood, clean their chimney, etc. 

Regulations and incentives to automate: In the United States, there is little regulatory pressure or incentives for manufacturers to automate.  The new Integrated Duty Cycle (IDC) test protocols are designed so that all types of stoves can be tested and to our knowledge the test method was not designed so that automated features would help a stove pass, though it is possible that will be the case. It is imperative that the National Residential Heating Task Force test the automated stoves on the market in the U.S. and give them the profile that other stove types are getting.  Currently, the test regimen may show the benefits of catalytic and hybrid stoves in the lab, without sufficient data or attention to how well cat stoves are used and maintained over their 10 – 20 year lifetime.  Automated stoves may also have maintenance issues over their 10 – 20 year lifespan, and it’s important to start assessing which automation strategies are more robust.

Test protocols are perhaps the best way to encourage manufacturers to innovate.  Protocols can make it harder for manually operated stoves to pass by requiring air adjustments that are likely to produce more smoke, unless sensors in the stove can adjust airflow themselves.  Making certification marginally tougher for non-cats to pass, leading to a growing percent of catalyst and hybrid stoves, is not an ideal solution compared to growing the number of automated stoves on the market.

At the state level, change-out and other incentive programs can start to recognize automated stoves and give them higher incentives.  Massachusetts is the only state that sought to provide incentives to automated stoves in a change out program in 2017 but it came too early and automated models were delayed coming on the marketplace.  States and air agencies can start to make consumers aware of this new type of wood stove, along with catalytic, non-catalytic, hybrid and pellet stoves. 

The lack of attention and support for the development of automated stove technology in the United States is connected to similar lack of support for cleaner pellet heating appliances.  Despite the ability of pellet stoves to emit very low levels of PM, the EPA allows them to emit the same level of PM as wood stoves, even though they have a different type of fuel, which should lead to stricter emission standards. In Europe, the EcoDesign Directive of 2022 requires pellet stoves to emit only half of what wood stoves are.  

The lack of “eco” or “green” labels for wood stoves in the U.S. has left manufacturers with little incentive to produce cleaner or automated stoves.  In Europe, some eco labels require pellet stoves, for example, to produce a quarter of the PM of wood stoves, and half of regular pellet stoves.  Manufacturers selling on the US market have mainly focused on achieving 75% efficiency, in order to qualify for the tax credit under IRS Section 25C.  Congress revoked that section, effective Dec. 31, 2025 and its unclear if it will be a permanent revocation or just for several years.  The credit has often lapsed since 2005, when it first began.  In Europe incentives have steered away from residential log heaters and focused on the best pellet stoves and boilers, which is a possible path forward in the U.S.

In Europe, some manufacturers feel that is not if, but when, they will have to start producing automated stoves. There is more urgency in Europe because of more widespread use of wood stoves in cities like London, and densely populated areas of Denmark, Netherlands, France, Germany and other countries. The German Blue Angel label and more local regulatory efforts, such as in Berlin, have also led to far more innovation and R&D on automation.  As in the U.S., lobbying by industry is slowing efforts at national and local levels to pass stricter measures that could lead to quicker adoption of automated stoves and more reliance on pellet stoves.

In early 2025, the European Commission released draft language of a new directive to take effect in 2027, including language that automation in stoves would be required. This led to strong industry push-back, and work on the new directive has been delayed.  The European Committee of Manufacturers of Domestic Heating and Cooking Appliances stated:

 

“The requirement of for automatic combustion control systems, additional testing, second conformity contradicts Ecodesign principles: it increases costs, energy consumption and maintenance need, limits technological neutrality and makes appliances more expensive.”
 
“Any Ecodesign regulation should not favour specific technologies. It should be technology-neutral and allow manufacturers to choose how to meet the regulation's requirements…. Although not explicitly required, a stove without a built-in catalytic converter and electrostatic precipitator is unlikely to meet the emission requirements. All seven known Blue Angel stoves have these features.”

 

This industry response to the draft of the next European Directive has many valid points which will also be part of the landscape in North America.  Regulators on both continents should shift their focus away from manually operated stoves and address these concerns and others as they move toward next-generation solid fuel heating solutions. One European study found automation reduced PM by 66% compared to one test method.

 

 

More resources on automated stoves

AGH blog, The Sensor Surge: Why equipment engineers are adding sensors everywhere - and why the wood stove may be next, July 2026.

Nordic Energy Research, Nordsyn EcoDesign, Task 2 Report, 2025

Eurocities, “Cities call for stronger EU rules on new wood-burning heaters to tackle deadly air pollution,” June 2025

AGH Webinar, “Harnessing Electronics for Cleaner, Smarter Wood Heating,” June 2025

14th U. S. National Combustion Meeting, “Forced-draft Airflow Control Tuned to Reduce PM Emissions in a Cordwood Room Heater Under Variable Operating Conditions,” 2025

 

Chemical Engineering Reactions. “Reducing Emissions from Current Clean-Burn Wood Stove Technology by Automating the Combustion Air Supply and Improving the End-User Interaction -Two Important Primary Measures,” 2023

 

IEA Bioenergy, “Design of Low Emission Wood Stoves,” 2022

 

Tarm Biomass, “Automated Wood Stoves: Technology Policies and Barriers,” 2017

 

Technical University of Denmark, “Guidelines for automated controls for wood stoves,” 2017

 

AGH Blog, “Automated stoves entering the marketplace,” 2014

 

AGH Blog, “Nine reasons manufacturers don’t use sensors in wood stoves,” 2013

DOE should focus resources on R&D to advance automated stove technologies

 The Department of Energy Bioenergy Technologies Office (BETO) released a Request for Information (RFI) seeking feedback on defining the goals and objectives for a planned effort to collect in-situ wood heater performance data in the field. The deadline to submit comments was September 30, 2024. John Ackerly, AGH President, submitted the following comment: 

There are a number of small portable
emission testing devices for wood stoves
that can be used in situ, or larger lab
equipment can be moved to a home.

"We believe BETO should minimize its role in funding in-situ testing efforts because in-situ testing is usually very complex and expensive, given BETO’s funding for residential wood heater technology development. There are many distinct objectives and reasons to do in-site testing, and stakeholders could eloquently make the case for any number of them. But given the size of BETO’s budget, we do not feel there is a compelling enough type of in-situ testing that is likely to be undertaken.

BETO’s mandate is to “support the development of cleaner burning, higher efficiency residential wood heaters” and it seems this has been interpreted more broadly over time, which is understandable to some point, given the dearth of high quality applications to develop next generation stove technology.

We would urge BETO to only fund in-site testing to the extent it directly focuses on modern, more automated stove technology. For example, it may be worthwhile doing some in-situ testing with an automated stove side by side with a traditional manually operated one, to provide data about how beneficial automation can be, if at all.

The list of questions in the Four Categories suggest that this RFI is wide-ranging without parameters related to development of cleaner burning, high efficiency residential heaters. In the United States, stoves must be tested for PM 2.5 to be certified for sale. Efficiency, as measured by B415, is not regulated, but tested and an existing IRS tax credit gives an incentive to hit 75% efficiency, HHV. Any new generation of more modern, cleaner and efficient wood stoves will need to focus on these metrics first.

To understand the potential of modern, automated stoves, it may be just as relevant to study pellet stoves, to understand how and why they have such a predictable emissions profile, compared to cordwood stoves. It is also relatively easy to test how clean and efficient pellet stoves are in-situ after 1 to 10 years in operation.

To achieve testing goals of how pellet stoves perform after 1 – 10 years of use, I would recommend simply using a Testo 380 and principally test for PM2.5, enabling more sampling of more devices.

There are a multitude of academic inquiries into residential wood smoke but BETO should first determine what avenues there are to more directly advance an R&D agenda, which could include emissions data showing how automation can reduce emissions. Cordwood furnaces have already made the transition from being manually operated to controlled by sensors, and the evidence is clear that sensors will keep a boiler or furnace far cleaner.

Some stakeholders who are heavily invested in manually operated stoves may want BETO to undertake in-situ testing studies, which can be endless. But one test of this RFI will be whether those stakeholders who are doing R&D on modern, more automated stoves need in situ testing data, and if so, what kind. Similarly, it may be instructive to see what kind of in-situ testing is recommended by stakeholders who regulate wood stoves, or are involved in health related studies.

BETO could consider doing an RFI on how to develop the next generation of wood stoves in the United States. R&D is perhaps the most important avenue but DOE funding in the solar, wind and geothermal sectors address scores of barriers to bringing a renewable technology to scale. Those barriers can also be addressed in the eco-system surrounding the wood heater community. Obviously, the wood heater sector will never have that level of resources, requiring a careful assessment of where scarce resources can best be used.

An RFI that engages this community on how to advance automated stove technology may help better understand why major manufacturers are hesitant or whether there are other initiatives that could be undertaken. In-situ testing may be one of them, but an RFI solely on in-site testing sends a confusing message to the wood heating community unless BETO better explains how it is part of a strategy to develop modern, more automated stove technology.

Comment on Massachusetts's Clean Heat Standard

The Alliance for Green Heat just submitted a comment to Massachusetts's Department of Environmental Protection concerning their Clean Heat Standard (CHS). To learn more about their CHS
check out this useful document. Ultimately, a CHS is a policy tool to require heating energy suppliers to gradually replace fossil heating fuels with cleaner heat over time by implementing clean heat or purchasing credits. Some would like to see the exit of advanced wood heating/automated wood heating from the CHS. The Alliance is in opposition to its removal. Please see our full comment below.

"The Alliance for Green Heat appreciates the opportunity to share comments regarding the Clean Heat Standard. We are a nonprofit that advocates for low- carbon heating strategies across the nation. We have a strong expertise in modern wood heating, heat pumps, and energy audits and weatherization, with a focus on low-to-middle-income households.

We believe that Massachusetts must keep advanced wood heating (AWH) technology in the Clean Heat Standard. AWH typically refers to pellet stoves and boilers at the residential level and can also include wood chips in larger systems. Residential wood stoves are not included in the definition of AWH because they do not have the automation to reduce particulate matter (PM) effectively and consistently. A similar term “automated wood heat” is often used and specifically excludes cordwood.

Advanced wood heating has a significant potential to be a complementary decarbonization technology that can increase electrification adoption for middle- income households and serves as an effective alternative heating source for energy providers to offer to customers.

Pellets for advanced wood heating are available locally in New England and are from sustainable sources, a mix of mostly sawdust from sawmills and wood chips from low grade wood. Many studies have investigated the use of woody biomass for local heating and have largely dismissed concerns that forest resources are being degraded to provide wood pellets. (See list of studies and peer reviewed scientific articles at the end of the comment.)

At the residential level, any state Clean Heat Standard should primarily focus on air source heat pumps – and weatherization services. In states with higher percentages of renewable electricity on their grids, heat pumps offer an excellent low carbon solution. However, there are still many drawbacks with heat pumps, many of which can be alleviated with back-up pellet stoves. High purchase and installation cost is of course one of the biggest issues with heat pumps. Pellet stoves can be installed for under $5,000 and can heat a home up to 2,000 square feet. Back-up wood stoves also provide an excellent source of heat when the grid goes down and gives rural consumers the confidence to switch to heat pumps (but we still do not advocate for including wood stoves as an eligible measure for obligated parties).

Because advanced wood heating systems use a fraction of the electricity that air source heat pumps require, its use in a house can reduce electric grid stress during the winter or reduce use of a back-up home battery. Wood pellet fuel has the added advantage of experiencing more price stability than both fossil fuels and electricity. For middle-income families trying to balance monthly costs, automated wood heating could provide a more consistent and affordable heating bill. Pellet boilers and stoves also have major disadvantages, including requiring far more maintenance and repair than heat pumps and repair technicians are not always easy to find. 

Equity concerns are significant for states designing Clean Heat Standards, and primary or back-up pellet heating is one measure that benefits rural low and middle income families. Giving those households the possibility of buying a more price stable fuel and one with an annual cost lower than air- source heat pumps is important. (Massachusetts Clean Energy Center). Another important measure is to ensure that energy auditors in Massachusetts include full inspections of wood and pellet stoves in energy audits. Old, unsafe polluting wood stoves should be eligible for removal but unless energy auditors are trained to do a safety inspection on them, this rarely happens. 

Pellet heating has a documented track record of delivering fewer CO2 emissions compared to electric baseboard heating, oil, propane, natural gas, and even air-source heat pumps with the current electricity grid (Massachusetts Clean Energy Center). (It is sometimes confused with carbon footprint studies on using pellets to make electricity in Europe, a far high carbon emitting application.) Removing a heating technology from the Clean Heat Standard that consistently performs just as well as other renewable energy and has the added benefits of greater price stability and local sourcing, would be misguided and not science based. In comparison, Vermont’s Clean Heat Standard includes automated wood heating. Vermont enthusiastically included this technology as their experience with the benefits of wood heating and ease of technology adoption has long been understood. 

Again, we thank the Department of Environmental Protection for this public comment opportunity. We hope that the Clean Heat Standard remains open to all viable low-carbon solutions to present the best possible outcome for Massachusetts to meet its clean energy and climate goals.

Further Resources:

Biomass Energy Resource Center. 2019. 2018 Vermont Wood Fuel Supply Study. https://fpr.vermont.gov/sites/fpr/files/Forest_and_Forestry/Wood_Biomass_Energy/Library/2018%20V WFSS%20Final%20Report%20with%20Letter.pdf.

Buchholz, Thomas, John S. Gunn, David S. Saah. 2017. Greenhouse gas emissions of local wood pellet heat from northeastern US forests. https://www.sciencedirect.com/science/article/abs/pii/S0360544217315451.

Biomass Energy Resource Center at VEIC. 2016. Wood Heating in Vermont. https://publicservice.vermont.gov/sites/dps/files/documents/Renewable_Energy/CEDF/Reports/AWH% 20Baseline%20Report%20FINAL.pdf.

Innovative Natural Resource Solutions LLC. 2007. Biomass Availability Analysis—Five Counties of Western Massachusetts. https://archives.lib.state.ma.us/bitstream/handle/2452/392593/ocn945986525.pdf?sequence=1&isAllow ed=y.

Olechnowicz, Casey, et al. 2021. Industry Leaders’ Perceptions of Residential Wood Pellet Technology Diffusion in the Northeastern U.S. https://www.mdpi.com/2071-1050/13/8/4178.

Maine Department of Agriculture, Conservation & Forestry. N.d. Wood Heat Maine. https://www.maine.gov/dacf/mfs/projects/woodheatmaine/index.html.

Renewable Energy Vermont and Biomass Energy Resource Center. 2018. Expanded Use of Advanced Wood Heating in Vermont. http://www.revermont.org/wp-content/uploads/FINAL-2030-Wood-Heat- Road-Map.pdf. " 

10 States sue the EPA to improve wood stoves, but the grounds are dubious

Old stoves removed during change out
programs range from ones like these ...

Ten states and one large air agency filed a notice that they intend to sue the EPA over its weak wood stove testing, certification and enforcement programs. The lawsuit is one of the only ways to keep the agency on the required timeline of updating its wood and pellet heater regulations every eight years. Otherwise, the agency can easily let timelines slip and put wood heater policies and regulations on the back burner as both Republican and Democratic administrations have usually done.

The Alliance for Green Heat (AGH) supports the lawsuit for these reasons: EPA needs to keep focused on this technology and keep doing the testing that can get better test methods and stoves that operate better in the hands of the consumer. Automated wood stoves that use sensors, computer chips and actuators to mix the fuel and the air, like in cars, probably offer the best hope for cleaning up wood stoves. But they may be left out of the next updated regulations, known as New Source Performance Standards (NSPS).

... to stoves that are decrepid
and/or dangerously self-installed.

However, AGH does not agree with much of the faulty narrative that says new stoves are not likely to be cleaner than old stoves. And maybe most worrisome is that the AGs of so many states appear willing to make such claims without citing data to support it. 

Unlike the dynamic around auto emissions, where car manufacturers are pitted against the EPA, in this case all fingers are pointed at the EPA for being too lax. The EPA’s wood heater program has had huge weaknesses and it is an easy target. But it is important to understand that the EPA is not a monolith, and it is the wood heater certification and enforcement programs in Washington that are far more of a problem than the section in North Carolina that does the test methods and change out programs.  

One of the many problems with the filing by 10 state Attorney Generals (AG) is that it is mainly based on a review of the EPA’s certification program done by the State of Alaska and Northeast   States for Coordinated Air Use Management (NESCAUM), with funding from New York State Energy Research and Development Authority (NYSERDA). It is not based on testing of new stoves in the field compared to old, uncertified stoves in the field. The narrative that the EPA has been wasting money on change-outs because new stoves aren’t necessarily cleaner than old ones seems to be gaining traction despite evidence to the contrary. Moreover, it distracts from the real, complex tasks at hand and is divisive. As a public relations strategy, it has been successful, gets good media coverage and rallies liberals.

The reality is far more complex. Ironically, it also misses what blue states care about: maximizing renewable energy in smart ways and creating more equity in the energy transition. Starting with the NESCAUM report, pellet appliances have been sidelined from the narrative and they are not even mentioned at a time when much of America is confused about the difference between premium heating pellets and industrial pellets to make electricity. If wood and pellet stoves are to play a role at helping the US reduce residential fossil fuel and protecting low to moderate income (LMI) households from the high costs of the new energy paradigm, it is vital for AG offices to understand the role of the technology in America. 

The Notice to Sue, likely leading to a lawsuit can be good for our common goals of getting cleaner wood stoves, but AG offices need to understand some things. First, we don’t need a new NSPS before we have new test methods. (One of NESCAUM’s many roles is providing data for new test methods, but compared to other labs, NESCAUM’s lab is way behind schedule, which complicates the whole timeline.) Second, the goal of getting better repeatability of a test result within a lab and between labs does not necessarily lead to a cleaner stove in the hands of homeowners. Third, tilting scales toward hybrid stoves may help in the short run, but is not necessarily a long-term or nationwide solution. Fourth, there has never been much agreement on what constitutes the best systems of emission reduction (BSR) in stoves which hinders the EPA in writing regulations that can force technology to change and improve. 

Wood and pellet heaters can help the nation in our transition to electrification by giving homeowners a back-up heating source, lowering stress on the grid during wintertime and providing LMI households protection from rising electricity costs which helps achieve equity. And environmental justice is improved in poor communities not just by a reduction in woodsmoke but also by improving energy security so that homes do not have to choose between heating and eating. For low-income households, change-out programs have been very important by removing unsafe stoves that pose a fire risk, improving not just ambient particulate matter (PM) and indoor PM, and adding heat pumps to many homes. 

The next NSPS will be best served by an EPA with the budget that enables them to collect their own data and properly manage the certification and enforcement programs, which are still far from effective. Underfunding leaves the EPA vulnerable to just reacting to one side or the other, and making poor decisions like revoking a cordwood test method that should have been changed and improved instead. That revocation was also prompted by the same group of states, most of which lack the expertise to understand the complexities and the politics of such a move. Tightening up that test method would have helped the EPA gather vital data it needs for this NSPS and not rely on data from parties who are sparring for an upper hand in the process.

The mostly blue states leading this lawsuit also need to manage wood and pellet heating far better in their own borders, as all states do. Vermont is a good model which is also heavily promoting heat pumps. States should be promoting pellet stoves and boilers and demanding stricter PM limits for those appliances. They should also limit the new installation of cord wood stoves in densely inhabited areas unless, or until, automation and mini-electrostatic precipitators can make cordwood units far cleaner. While cordwood stoves are essential for rural LMI households and help them get off fossil fuels, manually operated wood stoves are simply not a good energy solution where lots of homes are close together, particularly when the topography leads to frequent inversions, trapping PM close the ground where we breathe. 

As for the solution to reduce wood smoke in Fairbanks, even Albert Einstein would be scratching his head. Managers of that change-out program have done an admirable job and used many different strategies. They also uncovered huge problems in the EPA’s stove certification program which were hiding in plain sight. But we should not expect the next NSPS to make much of a dent in that intractable problem. 

Nationally, the solution lies in far more funding for R&D in stove technology, more attention to enforcement of current regulations, more experts for state AGs to rely on and collaboration. Like many big energy issues, the solutions are multi-faceted and rely on a collaborative approach by stakeholders. We should take this lawsuit as a wake-up call.

Alliance for Green Heat calls on President-elect Biden to support and help transform wood and pellet heating

Press release

Contact: John Ackerly

202-365-4765

Nov. 16, 2020 - The Alliance for Green Heat congratulates President-elect Joe Biden and Kamala Harris on their 2020 presidential victory and welcome their commitment to scale up renewable energy and energy efficiency.

This change of administration offers the United States a historic opportunity to reduce fossil fuels through a range of renewable heating solutions and energy efficiency measures. We have already begun to decarbonize our electric grid, and now it’s time to also focus on our heating sector which can reduce heating costs for families across the country, buoy economic recovery and create good-paying jobs.

The Alliance for Green Heat’s supports all renewable heating options as well as strategic pairing of heat pumps, geothermal, solar thermal and solar PV with wood and pellet heat technologies (our specialty). The role of decentralized renewable thermal technologies, including wood, solar thermal and geothermal is essential along with the electrification of heat as our electric grids slowly become more renewable. The electrification of transportation is creating massive demands for new generation and distribution. This combined with very high peak demands in the cold, short daylength northern tier of the country calls for strategic deployment and use of non-electric heating technologies. Rural areas need special attention given the cost of new infrastructure.

Executive Branch

The Biden Administration, through executive action, can immediately begin to drive markets toward beneficial forms of advanced wood heating. It is essential that Biden’s administration analyzes small-scale wood heating as having unequivocal carbon benefits. This includes:

• Ensuring there is an in-depth, science-based analysis to account for carbon content of wood used for residential and small-scale institutional heating that is separate and distinct from the analysis used for larger scale biomass to electric pathways.
• Use the power of procurement, as outlined by the Climate 21 initiative, to “bolster markets for climate friendly products such as … heating systems that use wood pellets” in federal buildings, starting with more rural buildings in colder climates.
• Directing the GSA to require rural federal buildings to consider heating with wood, chips or pellets where it is economically feasible.
• Prioritize an interagency working group on bioenergy to focus on small scale thermal wood.
• Include environmental justice considerations in bioenergy projects and expanding employment opportunities for Native Americans and low-income populations in rural areas.

Agencies

EPA: 

We urge the EPA, under new leadership to give more priority to one of the most popular and commonplace renewable energy solutions in the country. To this end, we encourage the EPA to

• Invest in the expeditious development and adoption of test protocols that resemble how homeowners use wood heaters (we use the term “wood heater” to include wood and pellet stoves, boilers and furnaces).
• Prepare the groundwork for a national wood stove exchange program to replace old wood heaters with cleaner alternatives.
• Put resources into the offices that certify wood heaters so that the process is expedited and includes a full review of all testing requirements
• Ensure the EPA’s Science Advisory Board (SAB) evaluates the carbon benefits of residential and small-scale institutional wood and pellet heating based on studies of how that wood is gathered and obtained by households and small institutions.

DOE:

• Issue a Statement on Scientific Integrity that reaffirms DOE’s commitment to renewable energy pathways that can be deployed in the short term, including wood heating.
• Expand the focus of the Bioenergy Technologies Office beyond liquid fuels to include biothermal and provide additional grants for automated, next generation wood heating technology.
• Develop strategies that utilize wood heating as an integrated approach to mitigate grid-load growth risks caused by rapid electrification in the country’s northern tier.

USDA:

• Prioritize the utilization of wood thinnings removed from high-hazard forests to be used for local heating of homes and institutions in those areas.
• Ensure Rural Development Housing programs allow for and encourage the installation of modern, automated wood heating.
• Increase funding to the Community Wood Energy program.

Congress:

We urge the Biden administration to work together with a closely divided Congress to:

• Incorporate the BTU Act into any renewable energy or tax legislation to ensure that the most carbon beneficial pathway for low-grade, bi products of sustainably harvested wood is included.
• Expand tax credits for energy efficient appliances including the cleanest and most efficient wood and pellet heaters,
• Expand funding for the DOE to continue the R&D program to modernize residential wood and pellet heating technology
• Establish a national program to retire older wood heaters in exchange for heat pumps, pellet heaters, and in some cases, new wood heaters.
• Ensure that weatherizing programs inspect wood and pellet stoves just as they do with gas and oil furnaces for both safety and efficiency and provide avenues for repair or replacement, if needed.

The Alliance for Green Heat promotes wood and pellet heat as a low-carbon, sustainable and affordable residential energy solution. The Alliance works to advance cleaner and more efficient wood heating appliances, particularly for low and middle-income families.  The Alliance runs the semi-annual Wood Stove Design Challenge to encourage innovation and automation in wood stoves. Founded in 2009, the Alliance is a 510c3 non-profit organization based in Maryland.