Government Report Says Wood & Pellet Heat Dominates Residential Renewables

Posted by Earth Stove on August 7, 2015 with No Comments as , , , , , , , ,
The 2014 Winter Fuel Outlook released by the US Energy Information Agency on Oct. 7, predicted that wood and pellet heating would continue the trend of being the nation’s fasting growing heat source.  Overall, wood and pellet heating grew 38% from 2004 to 2013, and now accounts for 2.5% of all home primary heating.
The EIA predicts wood and pellet heating will grow again in the 2014/15 winter by 4.7%.  Electricity is predicted to grow second fastest at 3.1%. Natural gas is at .07% growth and oil and propane are each predicted to drop by about 3.2%.  Regional data shows wood and pellet heating growing more than 7% in the northeast and Midwest, and only 2.5% in the south and 1.8% in the west. It was only two years ago that the EIA started to include wood and pellets in the 2012 Winter Fuel Outlook, even though far more homes have wood and pellet stoves than have oil furnaces.

Nationally, solar and geothermal dominate headlines and media imagery, but wood and pellet heating remain the dominant players in reducing fossil fuel usage at the residential level.  In 2014, the EIA says wood and pellet heat will produce .58 quadrillion Btu, or 67% of the nation’s total, while residential solar will produce .25 quadrillion Btu, or 29%.  Meanwhile, geothermal produces only .04, or 4%, and is not showing steady increases like solar.
While wood and pellets are the fastest growing heating fuel in America, residential solar is growing even faster in the electricity marketplace. At current rates, residential solar could produce more energy than residential wood and pellet stoves by 2020.  Solar has enjoyed generous taxpayer subsidies with a 30% federal tax credit in addition to state incentives.  The federal solar credit is set to expire at the end of 2016, but by then the cost of solar panels may have decreased enough for continued growth without federal subsidies.
Wood and pellet heating and solar are not competing technologies in that one produces electricity and the other heat.  They are often combined to make a home virtually carbon neutral, a process which is moving far faster in Europe than in the US due to higher fossil fuel prices and favorable government policies.  
In Europe, many countries are aggressively incentivizing higher efficiency pellet stoves and pellet boilers.   In the US, the Bush and Obama Administrations did not push for incentives for cleaner and more efficient pellet equipment but rather has let Congress and industry shape a tax credit without any effective efficiency or emission criteria.  As a result, the 38% growth of wood and pellet heating since 2004 documented by the EIA is not predominantly an expansion of cleaner and more efficient equipment, as it is in Europe.  Sales of cleaner pellet stoves are rising in the US, but the growth of wood heating in America includes some very polluting equipment such as outdoor wood boilers, also knows as outdoor hydronic heaters and new unregulated wood stoves, neither of which have emissions standards.  After many years of delays, the EPA is finally regulating these technologies and requiring them to meet emission standards by summer of 2015. 
Without effective federal regulations from the EPA, some states have been guiding the market toward cleaner and more efficient wood and pellet heating equipment, with Maine, Maryland, Massachusetts, New Hampshire, New York, Oregon and Washington taking the lead.

Heated Up!

Automated Wood Stove Features Entering the Marketplace

Posted by Earth Stove on July 27, 2015 with No Comments as , , , , ,

This year there are at least half a dozen stoves on the market that have some automated feature that didn’t exist on the market a few years ago. Many of these features help the stove burn somewhat cleaner, and are aiming at a demographic looking for easier operation. It’s still too early to tell how well the automated features work, compared to what they claim to do.

To truly understand the benefits of automation features, whether it be the traditional bi-metal coil or up-and-coming electronic sensors and on-board computers, you need to have side-by-side tests with the automation on and off. Easier said than done.  In Europe fully automated stoves – meaning stoves that you can “load and leave” – and the operator has no or limited control to adjust heat output, are already on the market.  None are on the market in the US as there is no test method to certify them.  The regulatory barrier to potentially far cleaner stoves from entering the US market is being addressed at the Collaborative Stove Design Challenge, where a automated stove testing protocol will be developed and submitted to the EPA.

Three major players in the US stove manufacturing community – Quadrafire, Travis and England Stove Works – now have automated systems to reduce start up and reloading emissions, which is one of the most important emissions issues that needs to be addressed. The Travis system uses electricity and is likely the most powerful of the three, and the other two don’t need electricity.  The England Stove Works stove has integrated their innovation in a very affordably price stove.

The real promise of automation is not to get a hot stove to hit an ultra-low particulate matter number in a lab, but to improve real-world performance by seamlessly optimizing performance throughout the burn cycle, to reducing start-up emissions and reducing emissions from unseasoned wood. EPA certification testing does not attempt to test these attributes of a stove, so stove companies have not had much incentive to invest a lot of time, effort and money to design for that.

In the United Kingdom solid burning heating devices are not classified by their size, i.e. stove vs. boiler, but by whether they are automatic or manual. To achieve a rating to be used in more polluted areas, manually operated stoves must submit lab tests showing 5 burns for each output level because “manually controlled appliances show much higher variation between tests.” Automatic appliances only have to be tested 3 times at each output level.

The chart below shows a wide variety of technology that exists in both stoves and boilers in Europe, but only exists in boilers in the U.S., and much of it is imported from Europe. (Click here for PDF that includes this chart and some discussion of these issues.)

In November 2014, Brookhaven Lab will be testing automated stoves and prototypes at a stove design workshop to see how effective they are. Their designers aspire to be part of a real trend of cleaner, more automated residential wood heating. But can they do it at an affordable price point? And, are consumers ready for them? Here, we will look at stoves with automated features that are already on the market.

A bi-metal coil acts as a heat-
sensitive thermostat which can partially
control the opening and closing of the damper.

1. The bi-metal coil. The oldest form of automation of steel wood stoves is the bi-metal coil which has been used on scores of stove models and is now mostly just used by a few catalytic stove makers, principally Blaze King and Vermont Castings. Some of the new automated features do something similar as the bi-metallic coil, but potentially do it much better. A bi-metal coil is simply a thermostat run by a metal coil that can close a damper down when its really hot, and open it up when its cooler. The stove’s air inlet can still be operated manually, but the bimetal coil will adjust the air inlet further. They tend to not work nearly as well on non-cat stoves, because the temperatures in a non-cat firebox can be more unpredictable, and if the coil shut down the air, or opened it too much, the stove would operate poorly – and critically – it adds far too much uncertainty in passing the EPA emissions certification test.

The rotating trigger mechanism in the
Smartstove Collection by Englander
reduces air flow once the stove is hot.

2. The next three stoves – the England Smartstove, the Quadrafire and the Travis – all use different automated approaches to starting the fire quicker and with fewer emissions. After the start-up period, the stove operates like any other. The Smartstove by England Stove Works was displayed at the Wood Stove Decathlon on the National Mall in 2013, but it was still being certified by the EPA so it was not part of the competition. The stove has an “automatic air setback mechanism” which is a primary air control with a rotating trigger which controls the opening and closing of air vents. When the operator starts a fire, they gives the stove maximum air and sets the trigger. When the stove gets hot enough, the trigger releases and primary air is reduced, while still providing ample secondary air.

Quadrafire’s Explorer 2 Start-Up air
control helps give the stove more
air in the first 25 minutes.

3. Another recent arrival on the market is Quadrafire’s Explorer II, which appears to provide similar automation. The website says “Automatic Combustion Control-provides the fire with air when it is most needed-leading to longer burns.” A marketing video says the operation is so easy that all you have to do is “load the wood, light the fire and walk away.” According to the installation manual, ACC is basically a timer which the operator must manually initiate with a control mechanism. Essentially, it opens the front air channel which allows air to enter for 25 minutes before closing. Once the front air channel is closed, manual controls are used to deliver preheated air to the top of the firebox to burn the rest of the unburned gases in the remaining three combustion zones.The Alliance confirmed with a company representative that no sensors are used or needed after the operator sets the timed control mechanism.

The slider on the Cape Cod
adjusts the rate of burns.

4. Travis industries Hybrid-Fire technology™ developed an automated “Greenstart” which shoots 1,400 degree air into the firebox for 15 minutes to start your fire, or when you reload. The Greenstart can significantly reduce start-up emissions, and emissions during reloading on a low temperature bed of coals, by jumpstarting the start-up process and heating the wood up faster than it would with newspaper. After the first 15 minutes, the stove has no automated features, but some of the Travis stoves that use catalysts are among the cleanest in the industry. The Travis Cape Cod stove won second prize in the Wood Stove Decathlon.

5. The Nestor Martin’s Efel has an “automatic mode” that can keep the room at a desired temperature. Or in timer mode, it can adjust the room temperature at a pre-set time. The stoves uses a simple ambient air thermostat in a remote control device that you can operate from the couch or anywhere nearby. If you don’t use it in automatic mode, the remote control allows the user to adjust the intensity of the fire just as you would with a manual air control. One of the key things that distinguishes this Efel from truly automated stoves is that there are no sensors in the stove that can prevent the stove from smoldering or override an adjustment by the operator that would make the fire smolder.

HWAM’s Autopilot technology uses
sensors, along with a bi-metal spring to
regulate combustion temperatures.

6. The final two stoves are more fully automated stoves and are on the market in Europe, but not in the US. Danish company HWAM, whose automation will be third-party tested and assessed at Brookhaven Lab in November, has integrated a new patented system-Autopilot. Along with the Austrian Rikatronic, described below, the Hwam is one of the most advanced and fully automated stoves in Europe. HWAM 3630 IHS features a control system that electronically measures combustion conditions through the use of a lambda oxygen sensor and a thermocouple. An onboard computer then allocates combustion air through three separate valves to help the consumer achieve the same results at home that are obtained in test labs under ideal conditions. According to the Danish Technological institute, HWAM stoves with this system are 17% more efficient and produce 40% more heat.

Rikatronic has a microprocessor-controlled
motor and a flame temperature sensor
which drives the RLS air distribution system.
The light tells you the optimal time to reload.
By pressing the button, the stove knows
 it has fresh wood to handle. 

7. There are numerous versions of the Rikatronic wood heater system. The Fox II stove features manual and automatic control settings. In manual mode the air distribution can be controlled in each combustion phase-even in the event of a power outage. Automation in Rikatronic technology works with a microprocessor-controlled motor and flame temperature sensor which operates the RLS air distribution system. Airflow in each of the 5 combustion zones is effectively adjusted for efficient burn. A red light indicates the optimal time to reload the stove. You can set the room temperature you want and once the required room temperature is reached, you can activate the eco mode by pressing the Rikatronic³ button. This causes the air supply to be optimally controlled to maintain the fire for as long as possible, without smoldering, and to leave behind as little ash as possible. Power consumption is 2 – 4 watts.

The first five stoves described here represent American innovations that can partially reduce excessive wood smoke, while the last 2 stove from Europe represents a more holistic approach that can help reduce emission not just in the start up, but throughout the burn cycle.  They are all still relatively new technologies and we are likely to see more companies improve upon them in coming years.


Heated Up!

Test Results, Presentations and Photos from the 2014 Collaborative Stove Design Workshop

Posted by Earth Stove on July 25, 2015 with No Comments as , , , , , , , , ,

Test Results

Updated on Nov. 24

Part of the Workshop rules was a requirement that teams had to publicly share their test results, which is a key part of the collaborative and educational process. During the Workshop, each team presented their test data to the 50 attendees who had the opportunity to discuss the results and give feedback to the  team.  Unlike EPA test, which starts when the stove is already hot, we used a warm start, capturing some start-up emissions, we used cordwood instead of crib wood and we used higher moisture content wood. Note: any gram per hour (g/h) references in the below test results are not comparable to g/h values from EPA test labs because we did not follow the Method 28 test protocol. 

1. MF Fire, the Mulciber. Powerpoint link.
2. The Kleiss stove. Powerpoint link.
3. Wittus Twinfire, Powerpoint link.
4. The VcV, PDF link.
5. Catalus Ventus, PDF link.

Team Presentations about their Stoves
Each team presented the concepts and technologies in the stoves. For a brief technical overview of all the stoves with contact info for the Teams, click here.

1. The Mulciber (powerpoint)
2. The Wittus Twinfire (pdf)
3. The VcV (pdf)
4. The Catalus Ventus (pdf)
5. Kliess (powerpoint)

Expert Presentations
During the Workshop, there were a series of expert presentations and webinars about automation, traditional stove technology, public health implications, air quality, regulatory issues and other relevant topics.

1. Dr. Tom Butcher, Brookhaven National Lab, Review of the Automated Stove Test Protocol (powerpoint)
2. Webinar with the five teams, hosted by BTEC.
3. Glenn Miller, Fairbanks Air District,  Technology Improvements vs. Behavior Modification (powerpoint)
4. Ellen Burkhard, NYSERDA, Renewable Heat New York (powerpoint)
5. Norbert Senf, MHA, Emission Testing of Masonry Heaters (powerpoint)
6. Gael Ulrich, Smoke Particle Formation Fundamental, (pdf)
7. Peter Cullen, Wohler SM 5000 (powerpoint)
8. Phil Swartzendruber, Puget Sound Wood Stove Retrofit Open Challenge (pdf)

Feedback Survey: Results of a 10 question feedback survey about the Workshop by teams, participants and organizers.

Photos: Day 1

Ivana Sirovica, Jessica Peterson and Jeff Hallowell, from ClearStak Brookhaven National Laboratory.

Rebecca raking coal bed to prepare for the next load of fuel. 
Thanks to John Pilger and Chimney Safety Institute of America and Olympia Chimney for donating pipe and installation!

Indigo Hotel in Riverhead NY – our base for the week

The Testo shows real time emissions, with top line showing particulate matter (PM)

Rebecca Trojanowski removes filters. The dark circle in foreground are the particulates on a filter from the test burn that will be weighed to determine grams per hour.

Even the kindling is carefully weighed so that each stove gets the same warm up rick.

Jessica Peterson from ClearStak working late into the night to prepare for testing tomorrow.


Photos: Day 2



Taylor Myers showing a thermal image of the Mulciber stove. 

Ben Myren, Tom Butcher and Eric Schaeffer firing up the New Zealand VcV stove. 

Lab in Bldg 815 with the VcV and Kleiss stoves.  (They brought 2 of exact same stove in case they needed it.)

Taylor Myers showing a real time digital display, using bluetooth, of temperatures in his stove.

Developed by ClearStak, this real time digital display shows 154 degree stack temperature, 529 in the firebox and 451 in the catalyst. Estimated efficiencies were in the mid-80s. 

Glenn Miller from the Fairbanks Air District on the left, Rob Rizzo from Mass. Dept. of Energy, and Gaetan Piedalue and Marc Suave from Polytest Labs, a EPA accredited test lab. Ellen Burkhard from NYSERDA is peering into the stove. 

Ben Myren, Tom Butcher and Eric Schaeffer firing up the New Zealand VcV stove.
The Wittus Twinfire’s downdraft mechanism, where the fire gets sucked into lower chamber and then passes through catalyts before going back up the stack.



Day 3

Corey Van, one of the young ClearStak staff that helped build the Catalus Ventus. 

Rebecca Trojanowski loads the Catalus Ventus.

The new Testo moisture meter that reads moisture without “pinning” the wood.
Norbert inspects the Condar, placed right below the triple walled pipe.
The tube on the right of black pipe is a Condar, which operates very similarly to a dilution tunnel. Norbert Senf is using it concurrently with the Testo PM analyzer.
A warm up test load made by Ben Myren. This top down burn, with smallest kindling on top, and larger kindling on the bottom is a very efficient way to start fires.

Amanda Aldridge of the EPA talks with Norbert Senf (behind flue pipe) about the Condar analyzer. Rob Rizzo from Mass. Dept. of Energy in upper right.

Electronic controllers that can be put in wood heating systems that were part of Jeff Hallowell’s presentation. Harold Garobedian in red jacket on right, and Rafael Sanchez from the EPA behind him.

A new Testo moisture meter that works without pins. It can measure moisture at the center of the wood, not on the edge.
George Wei hangs almost upside down to put a temperature sensor in the top of the flue pipe to measure stack temperature. This is a key data point for determining efficiency.

Day 4                                          
John Ackerly on opening day, welcoming everyone and talking about how automated stoves can solve many problematic issues issues that come with widespread wood burning.
From the left to right – Ellen Burkhard from NYSERDA, Lisa Rector from NESCAUM, Amanda Aldridge from EPA and Mark Knaebe from US Forest Service.
We spent hours in this room, having different presentations every hour, with lots of discussion and debate. Here, Ben Myren is presenting the testing results of the VcV stove.
Brian Gauld of New Zealand, John Pilger of CSIA and Jeff Hallowell of ClearStak.

Team Wittus Twinfire

Gregory Elliiot and Peter Cullen from Wohler, and John Pilger from Chimney Safety Institute of America.

Ingo Hartman, measuring glass temperature on his Twinfire stove.

We managed to find a BYOB restaurant which led to more red wine consumption. From left – Rod Tinnemore, Dave Misiuk, Amanda Aldridge, John Ackerly, Norbert Senf, Ellen Burkhard and LIsa Rector.


Final Day
The Catalus Ventus shows incredible hot catalyst temps compared to the both the stack and the firebox. This was during start up, when it was emitting maximum smoke, but between the catalyst, the fabric filter, virtually no smoke came out the stack.

Ivana Sirovica, a Research Fellow from Alliance for Green Heat, and Ben Myren, as Ben finished the final test of the week.

Tom Butcher using the Wohler particulate analyzer on the VcV stove. Because we used wood that was often above 25% moisture content, we had to deal with more moisture in our testing instruments.
Underneath the VcV stove is where the magic happens, and mechanical valves automatically close or open the primary or secondary air, depending on what the stove needs to maintain a clean and efficient burn. THis stove maintained a steady low burn rate with beautiful swirling flames in the upper part of the chamber.

Ben Myren shows how his thermocouples could read the temperature in 10 spots of the stove at all times. The top of the flue could be 250, when the air entering the catalyst was nearly 800, and 1300 in the firebox.

Brian Gauld, the owner of the VcV travelled from New Zealand, where there is also demand for automation that can improve stove performance far more than stoves are likely to perform when operated manually.

         Dr. Phil Hopke of Clarkson University and Mattian Woll of Testo.


Our cord wood was kiln dried and then shrink wrapped so it would maintain a constant moisture content. The wood was far wetter, on average, than wood used in EPA test certifications, which helped us assess how these automated stoves could perform with higher moisture content wood.
Preparation of kindling for the tests.
George Wei and Yussef were two of Brookhavens talented technicians. Both have worked on improving oil combustion systems, outdoor wood boilers and stoves.
The last stove is taken out, and demonstrates the challenge of testing the same day as removing stoves that are still hot! 


Heated Up!

Dec. 4 Webinar: Best Practices in Wood and Pellet Stove Programs

Posted by Earth Stove on July 24, 2015 with No Comments as , , , , , , ,
The University of Maryland Extension Woodland Stewardship Education program will host a one-hour webinar on Thursday, December 4th from 12:00 p.m. to 1:00 p.m. to provide an overview of the “best practices” in wood and pellet stove incentive programs across the United States. 
Sign up here.
As renewable energy programs grow around the country, more and more states are including incentives for wood or pellet boilers and stoves. Unlike other household appliances, such as refrigerators, furnaces or washing machines, wood heating equipment have no “Energy Star” labels for consumers to consult to make energy efficiency comparisons. Consequently, several states have devised a range of methods to determine the eligibility of cleaner and more efficient stoves and boilers.
This webinar will explore the features of these programs, and will use Maryland’s stove incentive program as an example of how one state met its goals for ensuring consumers purchase the most efficient appliances available. The speakers will identify what they see as emerging best practices in stove and boiler incentive programs as these initiatives become more mainstream.
This webinar features presentations from Jonathan Kays, University of Maryland Extension Natural Resource Extension Specialist; John Ackerly, President of the Alliance for Green Heat; and Emilee Van Norden, Clean Energy Program Manager of the Maryland Energy Administration.
The webinar is free and open to the public.  Sign up now to reserve a spot.
For related content: 

Heated Up!

Rookie Wood Stove Makers Get Highest Score in Design Workshop

Posted by Earth Stove on July 22, 2015 with No Comments as , , , , , , ,

Taylor Myers and Ryan
Fisher with the Mulciber,
the highest ranking stove.
A stove designed and built by graduate engineering students received the 
highest score in an international Stove Design Workshop focused on automated wood stove technology.  The goal of the event was to assess innovative technologies that can help stoves reduce real-world emissions that result from poor operation by the consumer and use of unseasoned wood, both of which are widespread problems. 

Ten judges scored the stoves based on emissions, efficiency, innovation, market appeal and safety.  The highest scoring stove, the Mulciber, adapted emission control techniques that are in automobiles, such as an oxygen sensor that controls the fuel-to-air ratio, a continuously engaged catalyst and an exhaust gas fan.  The Mulciber was also tested with unseasoned, 50% moisture content wood and performed quite well.   The team, who had never built a stove before the 2013 Wood Stove Decathlon, overhauled their first prototype and have now formed the company MF Fire to bring the stove to market.  

The Workshop was held at the DOE’s Brookhaven National Laboratory in New York and brought together a diverse range of stakeholders – students, professors, industry, regulators, air quality experts – who spent a week together analyzing the problems and solutions to residential cord wood emissions.

Five stoves competed in the event, which is part of the ongoing Wood Stove Design Challenge run by the non-profit group, Alliance for Green Heat. In 2013, the Design Challenge hosted the Wood Stove Decathlon on the National Mall in Washington DC, a high profile event modeled after the Solar Decathlon.  This year, the event was at a lab so that stoves could be tested more rigorously and test data could be shared with the participants.

The core problem is that most consumers do not operate wood stoves well and many use unseasoned wood.  In addition, EPA certification testing for wood stoves do not simulate how wood is burned in people’s homes.  For decades, manufacturers have been building stoves to pass that test, but not necessarily to burn cleanly in homes.  This workshop addressed that by testing with cordwood that was not fully seasoned, capturing some start-up emissions in the test and assessing how automation can reduce operator error.  At Brookhaven, stoves were tested at four parts of their burn cycle: warm start, steady state 1, hot reload and steady state 2. The current EPA stove certification test uses seasoned 2x4s and 4x4s and only tests for emissions after the start-up period, once the stove is hot.

Automated stoves, where computers, not consumers, adjust the air-to-fuel ratio, cannot be tested by EPA test methods so they are not able to enter the US marketplace.   A major goal of the Workshop was to start designing an alternative test method to the EPA’s method, so that automated stoves can be tested and become certified in the US, as they already are in Europe. Tom Butcher, a senior scientist at Brookhaven Lab, hosted one of the public webinars during the week on that topic.

Rankings: The judges gave double weight to emissions and efficiency, as they did in the 2013 Wood Stove Decathlon, because of the importance of those values.  This year, the judges decided not to judge affordability since most of the stoves were prototypes or technologies designed to be integrated into other stoves and ultimate costs and pricing was too speculative. Each of the 10 judges scored each stove on innovation and market appeal.  The other three criteria were based on lab tests.
“We want to congratulate the MF Fire team – and all the teams – for participating in a process of sharing innovation, ideas and test results,” said John Ackerly, coordinator of the event and President of the Alliance for Green Heat.  “These stoves have many of the solutions to excessive smoke from modern-day wood stoves and are challenging the EPA and the stove industry, to catch up with new technologies and new opportunities,” Ackerly said.

The Wittus team with the Twinfire.
While MF Fire stove, the Mulciber, had the highest combined score, several of the other stoves stood out in key areas.  The German Twinfire, designed by the Wittus team, had the second highest overall efficiency, at 74%, and one of the lowest emission rates on a test run.  Its automated air regulation enabled the stove to perform consistently well at different part of the burn cycle and it received the highest score for consumer appeal, for its downdraft flame into a lower chamber.  
The VcV, wired to monitor
temperature in key spots
The VcV, a New Zealand mechanical device that operates without any electricity, achieved the highest average efficiency, at 82% based in part on the lowest average stack temperature at 167 degrees (F), and the lowest emission rate on one of its tests.  It also received the second highest marks for innovation.  This was the only stove that did not require electricity and will be very affordable. Three out of four tests were very, very good, but on one the hot reloads, something happened and that reduced its overall numbers, and took it out of contention for first or second place.  This device has undergone extensive R&D and is one of the entries that is closest to being ready for the market.

The Catalus Ventus by ClearStak, received the highest score of all for CO reduction, and the second
The ClearStak team with the
Catalus Ventus

highest for emissions.   It was a highly innovative entry, employing dual cyclones, a pre-heated, continuously engaged catalyst and a fabric filter.  Its sensors and controller kept the oxygen rates incredibly steady, within half a percentage point. The technology could be integrated into a new stove, or added on to an existing stove. The designers did not try to optimize efficiency, which impacted their overall score.   

The Kleiss, ready for testing.
The Kleiss arrived at the competition with the hallmarks of an innovative, automated stove that could handle wet wood and nearly eliminate operator error.  The stoves sensors and algorithms were designed to maintain very hot combustion temperatures and to allow the operator to call for more of less heat, while prioritizing cleanliness.  However, the stove did not perform as expected, with secondary air contributing to primary burning with a large fuel load.   

Test results for all the stoves are available here.  (References to grams per hour are not comparable to EPA gram per hour tests since the Workshop used tougher test protocols.) A series of presentations by the stove designers about their stoves and other stove and combustion experts are also available.


The Wood Stove Design Challenge is a technology competition that also strives to bring key stakeholders together to assess and learn about new stove technology.  Primary funding came from the New York State Energy Research and Development Authority (NYSERDA), the Osprey Foundation and the US Forest Service.  Testing support was provided by Myren Labs, Masonry Heaters Association and Testo and Wohler, two German companies who are pushing the envelope of accurate real time lab and field testing of particulate matter.  The Chimney Safety Institute of America and Olympia Chimney donated the chimney installations, and Blaze King and Woodstock Soapstone also provided support.

The 12 member Organizing Committee oversaw developing protocols, testing and scoring and included representatives from Alliance for Green Heat, Aprovecho Research Lab, Brookhaven National Lab, Clarkson University, Hearth.com, Masonry Heater Association, Massachusetts Department of Energy Resources, Myren Labs, NYSERDA, US Forest Service and Washington Department of Ecology. The Committee is now considering options for a 2015 Stove Design Challenge.


Heated Up!

Best Practices in Wood and Pellet Stove Incentive Programs

Posted by Earth Stove on July 21, 2015 with No Comments as , , , , , ,
A report prepared for the University of Maryland Extension Woodland Stewardship Education program
By John Ackerly & Melissa Bollman

Alliance for Green Heat
October 31, 2014
As more and more states are beginning to provide incentives for modern wood and pellet stove installations, an array of criteria are being used to guide which stoves should be eligible and what other requirements should be included. This report looks at environmental, economic, energy efficiency, social equity, and consumer values and suggests ways to maximize program impact.
The federal wood and pellet stove incentive program that lasted from 2009 to 2013 is widely regarded as a particularly poor model. It allowed consumers to claim a $ 300 tax credit for the purchase of any new wood or pellet stove provided it was EPA certified (non-exempt) and at least 75% energy efficient. The energy efficiency requirement was quickly rendered meaningless as stove manufacturers were allowed to self-rate efficiency using any number of available methods. The EPA certification requirement, while it eliminated the highest polluting and most inefficient stoves, was similarly not sufficient for ensuring the best available technology was appropriately incentivized. Also, the federal program did not take important criteria such as professional installation and location into consideration. Thus, a new stove that emitted 5.5 grams of fine particulate matter (PM2.5) emissions per hour could be self-installed in a densely populated urban area and still be entitled to the tax credit.
A table summarizing all statewide incentive programs can be found at the end of this essay. Click here to download a pdf version of the report.

Summary of recommendations:
At a minimum, we believe programs should only incentivize wood and pellet stoves that are certified by the Environmental Protection Agency (EPA) and meet a stricter emission limit than the EPA’s minimum requirement. Energy efficiency is another important criterion that should be considered in stove incentive programs, although lack of reliable, independent data makes accounting for efficiency too difficult as of Fall 2014. To ensure new wood and pellet stoves work as cleanly and efficiently as they are designed, and to protect consumer safety and minimize the risk of fire, incentive programs should require subsidized stoves to be installed by certified hearth professionals. To ensure taxpayer funds for new stoves are spent in an efficient way and limit the negative environmental effects of wood smoke in urban areas, we recommend that new installs of wood stoves should be limited to rural areas, or that programs only make pellet stoves eligible for incentives. We also recommend that programs better target low- and middle-income residents.
There are several examples of state stove incentive programs that contain innovative and “best practice” features, but all programs have opportunities for improvement. We hope this report provides a resource for all programs.
1. Certification of equipment
Wood Stoves
Limiting the eligibility of wood stoves to EPA certified models is a basic feature of stove incentive programs.  The federal tax credit did not mention EPA certification, as it was supposed to be primarily an efficiency incentive.  Several unregulated boilers claimed to be eligible, but we are not aware of any uncertified stoves that claimed the credit.
The EPA provides a list of certified wood stoves available for download on its websitewith other useful information such as the stove manufacturer’s name, model name, emission rate, heat output in BTU per hour, and estimated or actual tested efficiency. Wood stoves certified by the EPA are independently tested to ensure they meet a particulate emissions threshold, which currently is 7.5 grams per hour for non-catalytic wood stoves and 4.1 grams per hour for catalytic wood stoves. Consumers can identify EPA certified wood stoves through a label affixed to the back or side of a stove as well as a hangtag, pictured below.
         EPA began certifying Phase II stoves in 1990, so some certified stoves are nearly 25 years old and need to be retired almost as much as some uncertified ones need to be. Stoves certified in the past 5 years are considered much cleaner and more effective than older, certified stoves.
Pellet stoves
            Pellet stoves are generally perceived to be cleaner and more efficient than wood stoves as a class, and few stove incentive programs have restricted pellet stove eligibility to those certified by the EPA. However, independent test data shows that this widely held belief about pellet stove efficiency may be incorrect. Some pellet stoves on the market are as low as 40% efficient, and many are in the 50% and 60% range, when they easily can be in the 70s given available technologies. We believe that households should not be subsidized into unwittingly buying a low-efficiency pellet stove that will saddle them with much higher fuel costs overtime. The list of EPA certified pellet stoves can be found on the same list as certified wood stoves. EPA certified pellet stoves are usually more efficient than their uncertified (exempt) counterparts because exempt pellet stoves often use the 35 to 1 air to fuel ratio loophole to avoid certification, at the cost of lower efficiency.
This issue will be obsolete at some point in 2015, when all new pellet stoves will be required to be certified under new EPA stove regulations.
Masonry heaters
Masonry heaters are such an expensive, niche product that they almost do not need discussion in these programs.  However, we encourage programs to make certain masonry heaters eligible, even though they are not certified. The EPA is currently considering a method to certify masonry heaters that may be released in the next year. In the meantime, Washingtonand Colorado maintain their own lists of certified masonry heaters approved for sale. These lists can be a useful reference for designing new stove incentive programs inclusive of masonry heaters. Coloradodoes not set a specific emissions limit, but maintains a list of over 30 approved masonry heaters by manufacturer. Washington sets an emissions limit of 7.3 grams per kilogram of masonry mass, which may be more useful to policymakers creating incentive programs. Washington may be setting the bar low, considering that the EPA has proposed a limit equivalent to 1.8 g/kg for future regulations.
2. Stricter emission limits
            While stove incentive programs in Montana, Idaho, and Arizonause EPA limits to set emissions criteria, several other stove incentive programs set stricter emission limits for eligible appliances than the EPA’s 7.5 and 4.1 grams per hour for non-catalytic and catalytic stoves. Setting stricter emission limits for wood stoves can help identify which stoves can perform best under optimal conditions. Some of the cleanest stoves by EPA emission standards may perform better in the real world. Equally important is using dry fuel and operating the stove correctly to obtain good real world performance. Pellet stoves, which operate in the field much more like they do in the testing lab as compared to wood stoves, should be held to 2 grams per hour, as in Maryland and New York’s program, or 2.5 grams per hour at the most, as in Oregon, Maine and the federal Housing and Urban Development (HUD)’s PowerSaver low interest loan programs.
The state of Washington has been a leader in establishing stricter state-wide limits. Currently they are 4.5 grams per hour for non-catalytic stoves and 2.5 grams per hour for catalytic stoves. Washington’s list of approved wood heating technologies, including masonry stoves, provides an easy standard policy makers can build into incentive regulations.
A state of Oregon incentive program requires stricter limits of 3.5 grams per hour for non-catalytic stoves and 2.5 grams per hour for pellet and catalytic stoves, which was adopted by Efficiency Maine’s stove incentive program. To take it a step farther, Maryland’s current limits are 3 grams per hour for wood stoves and 2 grams for pellet stoves. As the EPA continues to refine its certification criteria, we suggest that stove incentive programs adopt Maryland’s approachof limiting the eligibility of incentives to a certain grams per hour cutoff according to the data on the EPA’s certified stove list.
The argument against using stricter emission limits for wood stoves has some merit, but on the whole we and many other independent experts think it’s worthwhile.  It’s true that the test labs often know exactly how to test a stove, and can hit the stove’s sweet spots to get a low number of emissions that a consumer never will. Manufacturers that hire a test lab to do R&D on a stove before testing it may be likely to get even better numbers, because the lab is that much more familiar with the stove. The new EPA stove regulations are changing the test protocol, which may require stoves to burn cleaner on all test runs instead of averaging the test runs.  This could give emission numbers more relevance in the real world.
3. Efficiency
There is still no easy way to use efficiency in stove incentive programs, and as a result stoves are excluded from scores of state, local and utility incentive programs that are rooted in energy efficiency. Despite the benefits of having them included in incentive programs, industry has been reluctant to disclose efficiency numbers, much less agree to schemes where some stoves would get incentivized and other not.    
Pellet stoves are ideally suited to be part of many energy efficiency incentive programs, if they would release their tested efficiency values. Their continued exclusion may contribute to the perception that this technology does not fit into the mainstream energy efficiency movement, or worse, that it is not “green” enough to be included. Since one company, Hearth & Home Technologies, makes a very large percentage of the pellet stoves sold in the US, including many very efficient ones, they could significantly move the market by taking leadership and disclosing their actual, tested efficiency numbers.
Efficiency has become a thoroughly muddled, confusing, and controversial issue as they are several ways of measuring efficiency and results can be misleading. One of the greatest problems with this approach is the lack of third party tested efficiency data. The EPA list has verified efficiency data for only about two dozen units comprising mostly of the highest performing catalytic stoves. By only using stoves that have actual third party efficiency listing, a program would be basically limiting the selection to one non-catalytic Jøtul stove and a variety of large catalytic stoves. Only one pellet stove company, Seraph, has provided real efficiency data to the EPA thus far.  
Setting efficiency as an eligibility requirement would help encourage manufacturers to provide third party efficiency data to the EPA, which most have been reluctant to do in the past. The proposed new EPA stove regulations will require all stoves to be tested and listed for efficiency, but there is widespread concern that the EPA will not require, or even have the capacity to make, efficiencies available to the public within the first year or two after promulgation.

            The State of Oregon’s residential energy tax creditfor wood and pellet stoves is the only one that has put the effort into a workable and innovative system to incentivize the purchase of more efficient stoves without excluding inefficient stoves from eligibility. The more efficient the new stove is, the higher the tax credit the consumer receives. If the stove does not have an actual measured efficiency on the EPA list, the amount of the credit varies by stove type. Non-catalytic stoves are worth the least credit, catalytic stoves the second least, and pellet stoves the most. If the stove has an actual reported efficiency, then the consumer receives a tax credit based on how much more efficient the stove is than the minimum Oregon has established. The maximum rebate is $ 1,500.
 Both Massachusetts and Maine have attempted to use stove efficiency as an eligibility metric but the metrics were not clear or feasible and it had to be dropped.
A local utility program in Fort Collins, Coloradooffers homeowners zero-interest loans if they upgrade their wood burning appliance or fireplace to a more efficient class of heater, according to the default efficiencies provided by the EPA. For example, homeowners can upgrade an uncertified stove to a certified stove, or a wood stove to a new pellet stove, but not the other way around. This unique method of incentivizing the purchase of more efficient wood appliances has the potential to help consumers save money, but only if the EPA provided more accurate efficient data on pellet stoves. 
We find it is a good practice to include efficiency in the criteria, but we must acknowledge that the managers of these programs are struggling with some unintended barriers and consequences. Oregon is fixing one problem, which had led the tax credit calculation to favor non-catalytic stoves over the cleaner catalytic or pellet stoves. This put the agency in charge of the program, the Oregon Department of Energy, at odds with the Oregon Department of Environmental Quality. The Oregon tax credit amount is based on the efficiency improvement over the EPA’s default efficiency. So a non-cat tested at 70% would have a 7% improvement over the 63% default. A pellet stove tested at 75% would not have any improvement over the 78% EPA default efficiency. The program thus unintentionally puts pellet stoves at a disadvantage because the EPA has set unrealistically high default efficiency for pellet stoves.
4. Rebate amounts
Providing a higher rebate amount for pellet stoves than wood stoves is another common “best practice.” Maryland provides $ 700 for pellet stoves and $ 500 for wood stoves, steering households who may be on the fence towards a pellet appliance, which will be cleaner. With lower install costs for pellet stoves, the higher rebate may also be a reason more than 70% of consumers use the rebate for pellet stoves in Maryland. 
Right-sizing the rebate amount is also something that all programs must grapple with.  Funding that goes too quickly, or not quickly enough can sometimes cause problems. One money saving incentive that more jurisdictions are employing is bounty, or paying consumers $ 200-$ 400 to remove an old stove from circulation without replacing it with anything. For areas with excessive wood smoke pollution, this may be a far more effective per dollar of investment than a change out program.
5. Professional Installation
Requiring professional installation is standard for virtually all incentive programs. Wood and pellet stoves are potentially dangerous appliances and must be installed with the utmost concern for safety. Hundreds of homes burn down every year due to poor installations and lack of attention to clearances.
 Homeowners seeking to avoid the added cost of a stove installation are often tempted to self-install. In some cases, installation can be greater than the cost of a stove itself. State codes vary about permits and installation requirements for wood stoves, so state incentive programs that require professional installation can play a large role in helping to address this safety issue. Pellet stoves, which do not require a full chimney system, tend to entail less problematic, unsafe installs. However, with any appliance that presents a fire hazard, a professional installation by a hearth professional is a good practice.  
Options for incentive programs include requiring that stoves be installed by hearth professionals that have Chimney Safety Institute of America (CSIA) http://www.csia.orgor National Fireplace Institute (NFI) http://www.nficertified.orgcertifications. Another option is simply to require a certified contractor, or someone who has been approved to do specialty energy efficiency or weatherization work, install the stove. An added benefit of requiring hearth professional stove installation is that CSIA, NFI, and MHA would also be more likely to help advertise the incentive program if they are involved.
Most current state incentive programs, if they require professional installation at all, do not limit the eligible installers to hearth professionals. For example, Maine’s program initially required stoves to be installed by contractors with a solid fuel license, but did not provide for hearth professionals to do installations. In New York, a Energy Star professional is required.
Maryland’s program also initially required professional installation, but later waived the requirement after receiving a number of consumer complaints. Maryland began accepting self-installations provided that the owners provided documentation that the stove has been inspected post-install by either a county inspector or an insurance adjuster. While we believe requiring professional installation is the best practice, requiring inspection at a minimum can be a good compromise.
6. Low-income considerations
Some incentive programs offer higher rebate amounts to low-income families. This tends to be very common in change-out programs, and less common in non-trade out incentive programs. In New York, however, change-out of an old one stove is required to receive a rebate for a new one, unless the household is low-income, when the rebate is offered without a change out.
Change out programs tend to have limited budgets, but are usually very popular among consumers. Whether it’s a change out, or a straight incentive program, it is best if taxpayer funds are spent on consumer who need it most and not wasted on “free riders” who would make the purchase anyway without the incentive. When rebates disappear in a few hours or even a few weeks, it likely means the rebate was too generous and a lesser rebate could have resulted in a more installs.
To ensure stove change-out program funds benefit low-income consumers, the programs can be opened to them first and heavily advertised in low-income regions.
            Maryland considered a higher rebate for low-income families, but was dissuaded by added bureaucracy it involves and lack of data to demonstrate that it would be successful. 
            The use of income to qualify households for incentives or subsidies has had little support in renewable energy programs, even though it could be done relatively easily. Incentive programs for solar or geothermal rarely, if ever, disqualify families with high household incomes of $ 250,000 per year or more. Wealthy people like subsidies as much as low and middle-income people and it’s often very unpopular to steer taxpayer subsidies away from the richest families, who often have oversized homes.
As long as professional installation is required, incentivizing more affordable stoves from big box stores can make funding go much further and enable more low-income households to participate. Good quality EPA-certified stoves start at $ 700 and one of the most popular stoves in the country sells for $ 900. If stoves could be bought at a deep discount in bulk, program administrators may also get CSIA professionals to establish a discounted fixed price for a certain type of installation. Professional installation can be done by CSIA accredited chimney sweeps if local NFI trained staff at specialty hearth stores will only install their own products. Such a fixed price would be possible for pellet stoves and for wood stoves on single or two story homes where the pipe is mounted on the exterior of the house. If larger rebates are not provided to low-income families, this is a vital way to help them overcome high upfront costs.
7. Minimizing Free-Riders
A perennial problem with all rebate and incentive programs is that some people who take the rebate or the incentive would have made the purchase anyway, and so the funds serve little purpose.  Determining whether a program has a high or low number of “free-riders” is also difficult. 
            This is regarded as a cost of doing business for many rebate programs, such as those for purchase of Energy Star appliances. For stoves, the number of “free-riders” is far higher if consumers don’t learn about the incentive until they are making a purchase in a showroom.  However, if only the cleanest stoves are incentivized, and professional installation is required, programs can have the impact of resulting in cleaner, safer installs. They can also reward those manufacturers who invest more in R&D and produce cleaner stoves, spurring more innovation.
8. Household/area eligibility:
While pellet stoves can be acceptable in rural and more densely populated neighborhoods due to their more consistent low emissions, there are legitimate concerns about programs that encourage or subsidize the installation of wood stoves in densely inhabited or urban areas from a health and nuisance perspectives. Maryland’s program, for instance, is only available to homes that do not have access to natural gas, a backdoor way of limiting installs to more rural, sparsely inhabited areas where available heating fuels are expensive and residents can benefit the most from energy cost relief.  Initial data from the program shows there have been more wood and pellet stove grants awarded per capita in the more rural and less affluent counties than the more populated central region of the state, indicating there has been some success in this method.
A Woodstove Change-out Program in parts of Connecticut, Massachusetts and Rhode Island provided a $ 3,000 voucher to households who receive Medicaid, Low-income heating assistance, or the Women’s Infant and Children’s Nutrition Program.
Incentive programs can also work closely with low-income heating assistance (LIHEAP) programs, to ensure that families who receive LIHEAP are aware of the program and can access it.
Instead of using access to natural gas as an indicator of housing density, zip codes or counties could be designated as areas where an incentive may be appropriate. Another option would be to limit wood stove installs in more densely populated areas to only when an old, uncertified wood stove is being removed and recycled.
8. Energy Audit:
Energy audits are rarely used even in programs to incentivize modern, bulk fed pellet boilers, much less stove programs. But increasingly, incentives for stoves are available as part of a deeper energy retrofit that starts with an energy audit. Auditors can educate homeowners about the importance of upgrading to safer, more efficient equipment, spot dangerous installations, and assist in removing dangerous stoves. The Building Performance Institute (BPI) is taking the lead in developing guidelines for energy auditors to inspect wood stoves. Requiring energy audits in conjunction with professional installation would assist in states providing a more holistic energy service to consumers when incentivizing wood stoves. The Alliance for Green Heat and University of Maryland Extension produced a draft of steps to inspect a wood stove as a resource.
9. Dedicated outside air:
Several incentive programs in Oregon, Maine and in some HUD Power Saver programs require a dedicated outside air supply, but the requirement is far from accepted in hearth professional circles. In very tight homes, which are still relatively rare in the United States, outside air supply is important, but to require it for all homes not only adds a potentially unnecessary cost, it could even be a drawback.  If a home were found to be very tight, and has competing venting needs, such as a vented kitchen hood, a wood stove may compete for indoor air which could even reverse the flow of air down the chimney. In such a case, a dedicated outside air vent may be recommended for the stove. In Oregon, the requirement could mean simply a $ 35 vent that provides air within several feet of the stove. Many leading experts question the use of outside air.
10. Education:
Any program incentivizing new wood burning appliances should be coupled with educational materials on correct stove use and efficient burning practices. New appliances used incorrectly can negate the benefits of a new stove, contribute to more air pollution, and turn public opinion against wood burning and the program. It is well known that in terms of achieving ideal efficiency and cleanliness, choosing the right stove is only half the battle; the other half is the fuel and the operator. No matter how modern or clean a wood stove is, it is crucial that the operator use dry, split wood and give their stove enough air to maintain a clean burn. The EPA Burn Wise program, is a great resource for consumers that should be promoted by incentive programs. Consumers could even be asked when they receive an incentive to sign a pledge promising to only burn dry wood.  
11. Partners and Outreach
A “best practice” for virtually any incentive program is building a network of engaged partners who are committed to the particular goals of the program. For instance, if benefitting lower income populations is a goal, partnering with a local or state low-income heating assistance program can help get the word out to that population. Conversely, we found one incentive program in Alabama, where even the local hearth retail stores did not know it existed.
If the program is run by a state energy office, bringing in the expertise of the state air quality office is also important to ensure that agencies aren’t working at cross-purposes, as what happened in Oregon.
12. Reducing emissions
            Using a rebate or incentive to steer consumers toward the cleanest wood or pellet stove has some positive emission benefits on its own. Some states, such as Idaho, have for years required people to turn in an old, uncertified stove to get an incentive for a new one.  This resembles an ongoing, state-wide change-out, more than a stand alone incentive program, as it is not open to people who do not already have an old stove. Possibly the oldest continuously operating stove incentive program is in Arizona, where the state gives an incentive to put a EPA certified stove in a fireplace, to reduce the use of fireplaces for heating. And, in New York, the return of an old stove is waived for lower income families who want to buy a new pellet stove and do not have access to natural gas.
13.  Providing moisture meters and subsidizing wood sheds:
Moisture meters are effective yet inexpensive tools for ensuring homeowners only burn dry wood. One option is to provide a free ($ 10) moisture meter to every home that has a stove installed. One major woodstove manufacturer has begun to include a free moisture meter with each purchase of one of its wood stoves. States have the option of teaming up with the EPA’s Burn Wise program, which is promoting voluntary efforts like this to help wood stove owners burn cleaner and more efficiently.
Incentive programs could subsidize, prioritize or even require homes to have or build woodsheds. This would help ensure that subsidizing a new stove will result in reduced smoke from the home, or homes with woodsheds could receive a higher rebate, which incentivizes proper storage and educates people about its importance. An even more ambitious and more innovative concept would be to provide a firewood shed with every project. The EPA Burn Wise has a modular woodshed plan that cost $ 217 in materials and can be built off site or onsite.  Some experts question if a $ 150 rebate to help build a wood shed to keep wood dry may produce similar or more air quality benefits as a $ 1,000 rebate for a stove. The logistics of this is not necessarily easy, but it is something worth considering.
14. Monitoring and Evaluation
            Assessing the effectiveness of the program using agreed upon method is important. Many renewable energy incentive programs, including those that involve solar and geothermal, struggle with accurate and meaningful assessment often because the agency in charge of the programs wants to show it as a success.  Meaningful third party assessments can be expensive and may not be worthwhile unless the program is ongoing and there is an opportunity to change the program, something that outside interest groups may oppose. But tweaking program requirements is almost always necessary, and key stakeholders play a vital role in this. 
            For wood and pellet stoves, assessing the success of a program can be especially difficult because there is no easy way to meter heat output or fossil fuels avoidance. Particulate emission testing can be done in smaller, valley settings, but is difficult to monitor in state-wide settings.  Surveys of all participants via mail and email could be very useful and are an underutilized tool for gaining insights into program results. Surveys of hearth retailers can also be important.
Conclusion:
“Best practices” in stove incentive programs are likely to be increasingly important as more options for smart deployment become possible. States with more expertise and more background in wood heat are more likely to have ability to incorporate more best practices into their programs. Trying to include too many best practices can make programs too complicated for both consumers and the implementing agency, so it’s important for program designers to tailor the requirements to the program goals. Using a state’s program requirements for a solar incentive program is often a good starting place when developing wood and pellet stove incentive programs.
At this point in the evolution of stove technology, we feel that pellet stoves are particularly ready to be part of more incentive programs. However, public disclosure of efficiencies by manufacturers will make this process much quicker.
 Almost all programs have had to make adjustments after establishing requirements that did not work as planned.  While this is a normal part of the learning curve of establishing a program for any appliance or technology, we hope this short report may lead agencies to ask the right questions and consider effective options.



A Comparison of Eligibility Requirements for Stoves Incentive Programs
October 31, 2014


* This efficiency level was not measured or enforced in any meaningful way.
** This program only allows upgrades from lower to higher efficiency using the EPA default numbers.
*** MD and ME allow for professional inspection in lieu of professional installation.
**** No efficiency minimum; higher efficiency stoves get higher rebate amounts.

Heated Up!

Old-timey wood stoves need to get new-timey if we really want to make use of them

Posted by Earth Stove on July 19, 2015 with No Comments as , , , , , , ,

Monday, December 8, 2014
Nashua Telegraph
by David Brooks

Tom Butcher from Brookhaven Lab,
second from right, tests an automated
stove from New Zealand. Ben Myren,
left, did R&D work on it.

I don’t think very hard when I light up the old wood-burning stove in my basement. Turns out, that might be a problem.

“Combustion technology is incredibly complex. Numerous chemical engineers, combustion engineers, mechanical engineers around the world are constantly trying to understand the intricacies associated with combustion. It is absolutely not what you and I would think – just light a match … especially when you want to get clean combustion and use wood efficiently,” said Rob Rizzo, manager of the Renewable Thermal Program for the Massachusetts Department of Energy Resources.

Rizzo was among the organizers of the 2014 Stove Design Workshop held in November at Brookhaven National Laboratory in New York, the latest in a number of attempts to add some high-tech wizardry to that staple of New England life, the wood stove. (For details, see forgreenheat.blogspot.com/2014/11/rookie-wood-stove-makers-get-highest.html)

Why tinker with something as well-established as wood stoves?

Because, like me, most people don’t think too hard when using them, which makes them inefficient and polluting.

We use green wood or wet wood, and we fiddle with the damper in the wrong way, causing partial combustion and thus more pollution.

The Stove Design Workshop, like a national Stove Design Challenge in 2013 that featured two New Hampshire entries, wants to find technology that can better cope with our stupidity.

The five finalists in the design workshop used a variety of techniques to work around people, including oxygen sensors that control fuel-to-air ratio, a common emission-control technique in cars, and a New Zealand stove that has a “barometrically operated variable choke venturi tube” to control the amount of combustion air entering a stove, particularly at lower burn rates.

“The whole concept with the design challenge is to come up with solid-wood stove that eliminates the human interface. Basically hit a start button and walk away; that is the concept we’re aiming at,” he said.

This already happens with pellet stoves, of course, which is why pellets has led a wood-burning renaissance for building heat.

The drawback is that they burn pellets made of compressed sawdust rather than the wood I can snag for free off my property, especially after the Thanksgiving snowstorm knocked down so many big limbs.

The lure of free fuel means that a lot of people still burn non-pelletized wood for some or all of their heat, although it’s not clear how many.

I have never been able to find good data about people who use cordwood (a.k.a. “roundwood”) as their principal heat source, partly because it’s hard to pin down. I, for example, use it only as a minor supplement of the pellet stove in the living room and our oil-fired furnace.

Rizzo said he didn’t know any data either, but he said that wood stoves remain important, especially in western Massachusetts.

Just as important as convenience is cleanliness. Wood stoves can produce a lot of pollution, particularly fine-particle soot, that is a health hazard. This is particularly a problem around Keene, which has a lot of wood-burning stoves and a geography that traps air in certain weather conditions.

New Hampshire has used rebates to get people to turn in their old stoves for cleaner versions, although with limited success.

But those cleaner stoves aren’t all that great; they’re little more than old stoves with catalytic converters in the stovepipe. Hence the push to build a better mousetrap, so to speak.

“It’s exciting to see new ideas coming forward. We have some educated guesses but we need to do better,” Rizzo said.

“We need to collect more data, about efficiency, emissions, consumption volumes, and also source of wood, sustainability of wood source, quality of wood source. Because rural America is always going to be burning round wood.”

More info:

Heated Up!

EPA Declines to Release Efficiency Data on Wood Pellet Stoves

Posted by Earth Stove on July 18, 2015 with No Comments as , , , , , ,
On Thursday, the EPA said it would not release efficiency data on pellet stoves, one of the most popular renewable energy technologies in American homes.  About one million homes use pellet stoves in the United States, yet none of the major stove manufacturers disclose the tested efficiency of their products. 
The EPA recently set stricter emission standards for wood and pellet stoves, but did not require the disclosure of efficiencies of stoves currently on the market.
The Alliance for Green Heat filed a Freedom of Information Act (FOIA) request with the EPA on June 3, 2015 urging the agency to release stove emission and efficiency information.  In their response letter, the EPA agreed to release detailed emission test results and other data, but denied requests for efficiency information, leaving consumers in the dark as to whether they own a 50% efficient stove or an 80% efficient stove.  Click here for a copy of the EPA letter.
The Alliance for Green Heat filed the FOIA request because stove manufacturers routinely advertise misleading and exaggerated efficiency claims.  No federal or state agency requires manufacturers to use a common method of reporting stove efficiency in their promotional materials.
Most households use pellet stoves because they can save $ 500 to more than $ 2,000 per winter by using wood pellets in place of oil, propane or electricity.  However, the potential savings fluctuate widely based on the efficiency of the stove.
The EPA said they decided not to release the efficiency data because “trade secrets and commercial or financial information are exempt from being released” to the public.  Stove manufacturers claim that their efficiency information, along with almost all other data obtained from the certification testing is “confidential business information.” 
However, the EPA left open the possibility that it might release the efficiency values if the Alliance for Green Heat wants to receive a “final confidentiality determination” that would involve giving manufacturers an opportunity to substantiate their confidentiality claims.
John Ackerly, President of the Alliance for Green Heat said that the organization intends to seek a final determination from the EPA.  “Cars, furnaces and large appliances all have to report their efficiency and energy use to the public and this is a critical part of helping consumers save money and help the environment.  Why should there be a special exemption for pellet stoves?” Ackerly asked. 
“The lack of transparency on efficiency is holding this sector, as other forms of renewable energy are quickly gaining traction,” Ackerly noted. 
The new EPA wood heater regulations will require manufacturers to disclosure the efficiency of new wood and pellet stoves tested after May 15, 2015.  However, stoves that are already on the market will not need to be tested for another 4-5 years and will not be required to disclose their efficiency until this time.  Many manufacturers obtain efficiency data during their EPA certification tests and include them in their test reports to the EPA, although they do not release them to the public.  The FOIA was an attempt to get the EPA to release this information that it already has in its files.
Pellet stoves have a very wide range of efficiencies and manufacturers may claim that if they released the actual efficiency of their stoves it cold cause substantial harm to their competitive position, which is one of the reasons the EPA withholds business information.
Stove manufacturers are also hesitant to disclose efficiency information to their consumers because if their efficiencies are under 75%, their product would not be eligible for a federal tax credit that has often been retroactively renewed and requires a 75% minimum efficiency.  Since neither Congress, nor the IRS, nor EPA requires any standardized measure of efficiency, stove manufacturers can claim that nearly 100% of stoves on the market are 75% efficient.  If the EPA were to disclose actual efficiencies, it would make it harder for manufacturers to convince consumers that all their stoves were over 75% efficient.
The number of U.S. homes with pellet stoves far outnumber those with residential solar panels by a ratio of about 2:1.  Pellet stoves typically cost $ 1,100-$ 3,500, and have a payback period of 3-7 years depending on such factors as the price of the fossil fuel being displaced, the frequency the stove is used – and its efficiency.

Heated Up!

Wood and Pellet Stove Tax Credit Extended through Dec. 31, 2014

Posted by Earth Stove on July 16, 2015 with No Comments as , , , , , , ,
Stove manufacturers routinely claim
75% efficiency to be eligible for the
tax credit, even when stoves are far
below 75%.  The average wood and
pellet stove may be around 70%.

Updated on December 16, 2014 – A short term extension of the $ 300 federal tax credit to purchase a new wood or pellet stove was signed into law by President Obama on Dec. 19, after having passed the House and the Senate.

The law extends a host of tax provision through Dec. 31 2014, making it almost entirely a retroactive tax credit.   A two-year deal that would have extended selected tax credits through Dec. 21, 2015 fell through.





The tax credit, which started out at $ 1,500 applied to all stoves that were at least 75% efficient.  The stove industry used a loophole to help ensure that all EPA certified wood stoves and all pellet stoves could claim to be 75% efficient.  As a result, many consumers are unwittingly buying stoves that may be less than 60% efficient, or even less than 50% efficient.  Pellet stoves in particular can be very low efficiency, saddling consumers with unnecessarily high pellet fuel bills.

Because of this loophole, the stove tax credit has long been criticized in the energy efficiency community as being dominated by “free riders” because the credit applies to virtually every stove and does not push consumers toward the most efficient ones. Instead of giving consumers an incentive to buy higher efficiency or “greener” appliances, like Energy Star appliances that help people save money, the government has been giving a discount to all wood and pellet stoves (other than uncertified, exempt wood stoves.) 

Of the hundreds of stove models on the market, manufacturers have only disclosed actual, third party verified efficiencies for about 20 models and they are listed here. Blaze King is the only stove manufacturer who discloses actual efficiencies for all their models.  To date, all the major pellet stove manufacturers have refused to disclose any actual efficiencies.  Seraph Industries, a very small pellet stove maker, has disclosed their efficiencies and they are quite high.
The EPA, nor any other federal or state agency involved in wood and pellet stove education, warns consumers that they are not necessarily buying a 75% efficient stove, as promised by manufacturers who issue certificates assuring consumers that their stoves are eligible for the tax credit.
The Alliance for Green Heat has been a long-time advocate of a robust tax credit, but only for stoves that are genuinely cleaner and more efficient.  The federal tax credit has never incorporated particulate emissions into its eligibility requirements.
Consumers who bought a stove in 2014 can claim the credit on their 2014 taxes, assuming they have not exceeded the $ 500 limit for residential energy improvements.  

In addition to the federal tax credit, more states are beginning to offer incentives, including Idaho, Oregon, Maryland, Montana and New York.  

Heated Up!

20 Stunning Wood Fired Hot Tubs from Around the World

Posted by Earth Stove on July 14, 2015 with No Comments as , , , , , ,
Wood fired baths are an ancient tradition, dating back at least to Roman times when baths called hypocausts were built by running hot flue gases under a stone tub.  Those Roman tubs were also off the grid, as are these.  Some are quirky, some romantic, some practical and some just downright hedonistic.  Which is your favorite?
See our other photo essays: Wood Stoves from Around the World, and and Firewood Collection and Stacking from around the world. 

Heated Up!