Meet the teams: Backed by the EPA and DOE, top cookstove designers tackle the heatstove

This post is the sixth in a series introducing the 12 teams participating in the 2018 Wood Stove Design Challenge in November.

By John Ackerly, Ken Adler, and Shoshana Rybeck, Alliance for Green Heat

Cook stoves and international development 

Dean Still (left) with participants at an
Ethos conference near Seattle.

Dean Still leads the team at the Advanced Studies in Appropriate Technology Lab (ASAT) and has been involved with the international cook stove community for decades. He and his team have achieved many key breakthroughs in testing, stove design, instrumentation, and like most researchers and developers, they have had their share of dead ends, disappointments and flops.  

The New Yorker magazine featured Dean in a 2009 article about engineers who need to design stoves that cost no more than $10 so even the world’s poorest people can afford them. So, when we told Dean that cheap stoves by our standards were between $500 and $1,000, he laughed and said, “you would think that should be easy.”

ASAT won a $300,000 grant from the EPA to build a heat stove that makes electricity, thirty times more than the $10,000 that each team is getting from DOE through the Alliance for Green Heat. ASAT has another advantage that only a few teams have in the competition: they operate a testing lab so they can measure changes in emissions and efficiency with each iteration of the prototype.

ASAT's sister group, Aprovecho hosts
annual "stove camps" where innovators
work together to built and test designs

The challenge for ASAT is whether they translate their experience and skill making cookstoves into a successful heating stove that performs well in the lab and in the field. There is a tight timeline and ASAT is new to the way the EPA measures PM and efficiency for heat stoves—and the way that tests will be conducted at the Stove Challenge. Translating lab test protocols to real world emissions may be even tougher for cook stoves and oversight of cook stove labs is weak compared to EPA-approved heat stove labs. But the cook stove community is far more transparent, and test results and technologies are more freely shared in the common battle of a global enemy—daily exposure to wood smoke from traditional cooking practices.

ASAT’s strategy

Dean Still with Prince Charles, who
has been an advocate for the modern,
cleaner cookstoves

ASAT’s stove is unique from the start—it’s a rocket stove.  Rocket stoves are most common as a developing world cook stove where you feed small diameter fuel into an insulated chamber and let it burn the ends of the sticks. Rocket stoves designed for heating are usually called “rocket mass stoves” but the prototype coming to the competition in November 2018 will be a new, high tech, low mass hybrid of the Rocket stove.  

ASAT is using an expansive strategy and are integrating many innovative technologies, from fabric filters to laser smoke sensors that automatically adjust secondary air.  By keeping an open mind, the ASAT team is winnowing down technologies, but the danger is that they are doing this on a very short time-line and the prototype is still going through major changes with less than 6 months prior to the competition.

ASAT's lab in Cottage Grove, OR

ASAT is working to make a stove mostly for the Asian market that can benefit those who struggle to get heat and electricity independently with ultra-low emission rates. The stove will include an electrostatic filter for PM to capture escaping emissions. Dean says his stove will have “jets of pre-heated secondary air that create a zone of mixing like in the carburetor of a car where a combination of high temperatures, residence time and complete mixing result in close to complete combustion. The fan speed, the amount of smoke, CO, CO2, and temperature in stove will be shown on a LTD screen. A PM sensor in the chimney automatically adjusts the velocity of the secondary air jets.”

Thermoelectric technology 

With help from the EPA, ASAT is developing a stove that can be used to cook food, heat the home and create electricity mainly for rural households in Asia that have intermittent or no electricity. To do this, electronic designer and manufacturer Karl Walter and lab manager Sam Bentson have created a new type of TEG that fits into the evolving design. The team is currently working on the fifth iteration and are focusing on how to create reliable electricity in the most inexpensive way possible. 

Sam Bentson, ASAT Lab Manager

The team has been building their own TEG that is making electricity without the use of a water cooling system. Instead, their TEG uses a large radiator that is essentially an aluminum fin designed to move the most air at the lowest wattage possible. With the team solely using a radiator and not including a water cooled system, or even a fan, the model is far less expensive, which appeals to ASAT's dedication to making this as affordable as they can. The team hopes to develop a TEG for less than $100 that creates at least 15 watts of power, using a switch mode voltage regulator and usb connection. Karl Walter says, “Water cooling is great but there is also something to be valued in a simpler, robust approach.”

Creating an affordable cook stove with an attached TEG that does not have “moving parts” is no easy task. Thankfully, with the financial support of the DOE and EPA, ASAT has been able to fully delve into this project and work through the challenges they have faced. Karl says that for their team the largest challenges had to do with temperature differentials and power outputs. He says that finding a “realistic power output was difficult” as well as figuring out “what happens when you overheat the stove.” But, the team is on a two year contract for their EPA project and with a year remaining, they are optimistic about the future development of their product and plan to have a model prototype ready for market testing within the next 4 months.

ASAT follows the old adage to think globally and act locally. Their efforts to create stoves that benefit people around the world have had tremendous support from national and regional organizations and they hope to expose the powerful technology they’ve been working on to a larger audience at the challenge in November. 

Contact the team at:

Dean Still
managerstovetec@gmail.com

Sam Bentson
managerstovetec@gmail.com

Karl Walter
karl@waltech.com

West Penn Power Energy Fund to support a design competition that pairs automated, electricity producing wood stoves with solar PV

June 27, 2018- The Alliance for Green Heat received a $5,000 grant from West Penn Power Sustainable Energy Fund (WPPSEF) to support the 2018  Wood Stove Design Challenge, a competition to automate and make electricity from wood stoves from November 9 - 13.

The grant funds will be used to test and promote stoves that are automated and produce electricity, both of which could be popular in Western Pennsylvania as they become more commercially available in the next few years. Twelve teams are competing and they will be rigorously tested for emissions, efficiency, electricity output and other qualities.,

Automated wood stoves can enable consumers to “load and leave” and get a high efficiency clean burn through sensors that can adjust by the minute and are far more effective than a human operator. Electricity producing stoves can recharge cell phones, power light bulbs in the event of a short or longer power outage caused by storms, grid failure or any other reason.  Within 3 – 5 years, electricity producing wood stoves may also be a more common option in the northern US to complement low wintertime solar PV output. In the future, thermoelectric wood stoves may be able to produce half as much electricity as a residential solar PV installation in December and January in northern states.

Wood is a popular residential heating source in Pennsylvania. According to the latest Census figures, Pennsylvania has the highest number of households heating with wood outside New York and California. Approximately 3% of all homes in the Commonwealth use wood as a primary heating source, but in 16 counties, 10% or more of households use wood or pellets as a primary heat source according to the US Census: Fulton (20%), Sullivan (20%), Juniata  (19%), Forest (16%),  Potter (16%), Tioga (15%), Susquehanna (15%) and Bradford (14%), Bedford, (13%), Huntington (13%), Mifflin (13%), Perry (13%), Crawford (11%),Wayne (11%) and Warren (10%).  More than half a million Pennsylvanians use it as a primary or secondary heat source.  

“Woody biomass is an abundant renewable heat feedstock which has been used by generations to provide low-cost heating for homes across Pennsylvania.  WPPSEF seeks to better understand how modern, innovative wood stoves can affordably help meet energy needs while operating far more cleanly than traditional wood stoves,” says Joel Morrison, Director of the WPPSEF.

The Alliance for Green Heat promotes modern wood and pellet heating systems as a low-carbon, sustainable and affordable energy solution. The Alliance works to advance cleaner and more efficient residential heating technology. The Wood Stove Design Challenge in November 2018 will the fourth Design Challenge hosted by the Alliance for Green Heat. Founded in 2009, the Alliance is an independent non-profit organization and is tax-exempt under section 501c3 of the tax code. 

The West Penn Power Sustainable Energy Fund (WPPSEF) is a 501(c)(3) nonprofit organization that invests in the deployment of sustainable energy technologies that benefit West Penn Power ratepayers in Pennsylvania. WPPSEF investments are focused in three broad categories:

✓     Deployment of sustainable and clean energy technologies; 

✓     Deployment of energy efficiency and conservation technologies; and 

✓     Facilitating economic development, environmental betterment, and public education as they relate to sustainable energy deployment in the WPP service region.

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Visit http://www.wppsef.orgfor further information.

Contact John Ackerly, 

Alliance for Green Heat, 301-204-9562
jackerly@forgreenheat.org

Contact Barbara Robuck, 

West Penn Power Sustainable
Energy Fund, 814-865-7380
wppsef@ems.psu.edu

West Penn Power Energy Fund to support a design competition that pairs automated, electricity producing wood stoves with solar PV

For immediate release

June 27, 2018- The Alliance for Green Heat received a $5,000 grant from West Penn Power Sustainable Energy Fund (WPPSEF) to support the 2018  Wood Stove Design Challenge, a competition to automate and make electricity from wood stoves from November 9 - 13.

The grant funds will be used to test and promote stoves that are automated and produce electricity, both of which could be popular in Western Pennsylvania as they become more commercially available in the next few years. Twelve teams are competing and they will be rigorously tested for emissions, efficiency, electricity output and other qualities.,

Automated wood stoves can enable consumers to “load and leave” and get a high efficiency clean burn through sensors that can adjust by the minute and are far more effective than a human operator. Electricity producing stoves can recharge cell phones, power light bulbs in the event of a short or longer power outage caused by storms, grid failure or any other reason.  Within 3 – 5 years, electricity producing wood stoves may also be a more common option in the northern US to complement low wintertime solar PV output. In the future, thermoelectric wood stoves may be able to produce half as much electricity as a residential solar PV installation in December and January in northern states.

Wood is a popular residential heating source in Pennsylvania. According to the latest Census figures, Pennsylvania has the highest number of households heating with wood outside New York and California. Approximately 3% of all homes in the Commonwealth use wood as a primary heating source, but in 16 counties, 10% or more of households use wood or pellets as a primary heat source according to the US Census: Fulton (20%), Sullivan (20%), Juniata  (19%), Forest (16%),  Potter (16%), Tioga (15%), Susquehanna (15%) and Bradford (14%), Bedford, (13%), Huntington (13%), Mifflin (13%), Perry (13%), Crawford (11%),Wayne (11%) and Warren (10%).  More than half a million Pennsylvanians use it as a primary or secondary heat source.  

“Woody biomass is an abundant renewable heat feedstock which has been used by generations to provide low-cost heating for homes across Pennsylvania.  WPPSEF seeks to better understand how modern, innovative wood stoves can affordably help meet energy needs while operating far more cleanly than traditional wood stoves,” says Joel Morrison, Director of the WPPSEF.

The Alliance for Green Heat promotes modern wood and pellet heating systems as a low-carbon, sustainable and affordable energy solution. The Alliance works to advance cleaner and more efficient residential heating technology. The Wood Stove Design Challenge in November 2018 will the fourth Design Challenge hosted by the Alliance for Green Heat. Founded in 2009, the Alliance is an independent non-profit organization and is tax-exempt under section 501c3 of the tax code. 

The West Penn Power Sustainable Energy Fund (WPPSEF) is a 501(c)(3) nonprofit organization that invests in the deployment of sustainable energy technologies that benefit West Penn Power ratepayers in Pennsylvania. WPPSEF investments are focused in three broad categories:

✓     Deployment of sustainable and clean energy technologies; 

✓     Deployment of energy efficiency and conservation technologies; and 

✓     Facilitating economic development, environmental betterment, and public education as they relate to sustainable energy deployment in the WPP service region.

-->

Visit http://www.wppsef.orgfor further information.

Contact John Ackerly, 

Alliance for Green Heat, 301-204-9562
jackerly@forgreenheat.org

Contact Barbara Robuck, 

West Penn Power Sustainable
Energy Fund, 814-865-7380
wppsef@ems.psu.edu

Meet the teams: Fighting global warming with a gravity fed, thermoelectric pellet stove

This post is the fifth in a series introducing the 12 teams participating in the 2018 Wood Stove Design Challenge in November.

By Ken Adler, and Shoshana Rybeck, Alliance for Green Heat 

Jill Elsner (CEO) and Fred Leavitt (VP) 
using a modified version of their
Greenway Power Stove to power a light bulb.

Fred Leavitt has been working in thermoelectrics since he graduated from college in 1982. He learned the technology from the team that developed the SNAP-27 thermoelectric generator left on the moon by the Apollo missions, as well as the team that developed the thermoelectric generators for the Voyager spacecraft. Now, as Vice President of Hi-Z Technology, he wants to bring that technology to your living room. 

Fred developed a thermoelectric pellet stove twenty years ago, but the thermoelectric modules were too expensive and the market wasn’t ready. With dramatically lower module costs, Fred is looking to do more than just “power lights.” Hi-Z, in collaboration with Northwestern’s Department of Material and Engineering Science, will be adding a custom made thermoelectric generator (TEG) to a WiseWay pellet stove for the 2018 Wood Stove Design Challenge.   

Hi-Z Technology is a powerhouse of thermoelectric expertise. Founded in 1988, it is a California R&D business of engineers and technicians who design, develop and manufacturer bulk thermoelectric modules and generator systems. Hi-Z, along with ASAT, another team in the Wood Stove Design Challenge, also received a $300,000 grant from the EPA to work on thermoelectric cook stoves.

Fred’s goal for the WiseWay is to produce about 100W of power, enough to recharge a home battery, supplement photovoltaics, power lights and small appliances, and provide potable hot water. 

Wiseway stove prior to modification

The WiseWay, invented by Gary Wisener, was certified by the EPA in 2012 and later bought by US Stove. It was the first and remains the only gravity-fed pellet stove on the US market that does not need electricity. The stove is thus an ideal candidate to produce electricity as it's often used off-grid in homes that need more reliable electricity, particularly in the winter. 

Fred is adding a water-cooled TEG near the combustion chamber, technology that Fred says “is simple, but works.” He likes pellet stoves because the combustion chamber has less temperature fluctuations compared to cordwood stoves, which improves TEG power output and longevity. Fred plans to cool the water with a hydronic radiator, which would allow the WiseWay to heat more than one room in a home and provide hot water for cooking and cleaning. 

Come November, Hi-Z plans to bring their new and improved stove complete with a water-cooled electric generator to the challenge. Fred and his team are also working to eliminate the need for manually igniting the stove with a propane torch by adding a battery-powered heating element. They are also exploring the addition of a DC-powered exhaust fan to improve combustion.  

The Hi-Z team recharging a cell phone
from one of their cook stove designs.

The development of the thermoelectric WiseWay has had minimal technical struggles. However, Fred notes that the team has faced considerable challenges making the model “cheap enough to make it a commercially viable product.” The team is determined to showcase a thermoelectric pellet stove that is easier to operate, can reliably produce electricity, heat and hot water, and is affordable.  

Goals for the Team

Fred's career has consisted of many projects that aim to reduce human contributions to climate change and sees the Wood Stove Design Challenge as a major opportunity to help homeowners get off of fossil heating fuel. Bringing this stove to market is likely to spark the interest of homeowners looking to heat with pellets, secure a back-up or secondary electricity source and reduce their overall carbon footprint. That is why Fred and his team “firmly believe in making pellet burning stoves major players in the fight against climate change.”  

Contact the team 

Fred Leavitt

f.leavitt@hi-z.com 

Jill Elsner
j.elsner@hi-z.com

Meet the Teams: An aerospace university department tackles an earthly challenge: electricity from a wood stove

This post is the fourth in a series of blogs introducing the 12 teams participating in the 2018 Wood Stove Design Challenge in November.

By Ken Adler and Shoshana Rybeck, Alliance for Green Heat 

Alexus, Connor, and Jack
with the Englander-30 NC stove. 

With the 2018 Wood Stove Design Challenge taking place on the National Mall this November, it is only natural that one teams is only a couple metro stops away. Students from George Washington University School of Engineering and Applied Science’s Department of Mechanical & Aerospace Engineering (GWU SEAS MAE) have been hard at work  developing a thermoelectric stove. Students from this department are more likely to work on nanotechnology in solar panels or landing spacecraft on Mars, but it turns out, getting a steady flow of reliable electricity from a wood stove is just as challenging.

What started as a class assignment quickly became  an imperative learning experience for team members, Alexus Camero (‘18), Connor Itani (‘18), and Jack Eaton (‘19). As students in the Department of Mechanical & Aerospace Engineering, Alexus and Connor both took a thermo-systems design class taught by Professor Saniya LeBlanc.  With Connor’s interest in green electricity and Alexus’ major relating to heat transfer, the duo took on the task of creating a thermoelectric stove to bring to the competition this November. With the necessary grants in place, and a stove donated by England’s Stove Works the Team began designing their thermoelectric generator (TEG) stove  in the Fall semester of 2017.

Dr. Saniya LeBlanc in her lab 

at George Washington University.

Later, their Team grew a little larger, when Jack Eaton joined Alexus and Conner working in   Professor LeBlanc’s lab. Jack says that he was personally drawn to this project for two reasons, one being that “working in his advisor’s lab gives him a lot of autonomy”, something that is invaluable for an innovative college student, and second that he “spent every winter in middle school and high school in New Hampshire and knows many people that use wood stoves and struggle to pay their heating bill.” Jack, Alexus, and Connor all  have personal, academic, and innovative drives for this challenge, which has kept them determined throughout the development process.

The team has been working with Professor  Saniya LeBlanc to design and create the most efficient thermoelectric stove  possible. As of now, their model is using thermoelectric modules by TEGMART that are designed to produce a maximum of 200 watts of electricity under optimal heating and cooling conditions, which is 86° F (30° C) for the cold side and 572° F (300° C) for the hot side of the module. Achieving these optimal temperatures in real life applications is a major challenge so actual power output is expected to be substantially less than the rated power.  

The Englander 30-NC in the lab.

Launching their model

Not all their challenges are technical. Operating a wood stove in downtown Washington, DC required the  Team to maneuver through a number of school and local government hoops to get approval for testing their stove.  Nevertheless, the team has recently finished this taxing process and is on to the testing phase. But, the testing phase has its own challenges as well. The team  recognizes that their stove’s heating and cooling system will require substantial improvements if it is going to maximize the TEG’s power output. As of now, the TEGs  are located on the steel stove top. Steel is not as good a conductor of heat as aluminum, so the Team will be conducting tests to determine if there is sufficient heat flow through the steel stove top.  The cold side of the TEG is cooled by water that is pumped through a 3 foot long baseboard heater.  However, the team is exploring the option of adding a fan to improve cooling. In a home setting, the water could be pumped through baseboards located in multiple rooms, which would allow for a much greater release of heat to cool the return water.  

View of the Englancer-30 NC
from the top. 

The trio is excited to showcase their model at the challenge to show how they retrofitted the EPA certified Englander 30-NC stove  to make electricity, and “limit the amount of heat that is lost” to improve the overall efficiency of the stove.  However, this competition also has personal messages for them. With an academic focus on heat transfer, one of the team’s recent graduate’s, Alexus, has been especially motivated to learn about how thermoelectric modules can convert heat into electricity.  For Connor, the team’s other recent GW graduate, this project has been all about “taking a concept from the drawing board to reality, from conception to completion, and how to deal with unforeseen challenges along the way”. This summer is expected to be an important time for their final developments. With testing commencing within the next month, Alexus, Connor, and Jack are looking forward to being in the lab this summer, working to get their model ready for competition day.  

Contact the team

Alexus Camero

alexuscamero@gwmail.gwu.edu

Connor Itani

connor@gwmail.gwu.edu

Jack Eaton

jeaton19@gwmail.gwu.edu