Wednesday, July 11, 2018

Meet the Teams: A micro CHP pellet unit makes its debut on the Washington Mall

This post is the eighth 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

The Pellematic e-max with a cut-away
view of the Qnergy Stirling engine that
makes the electricity.
If all goes as planned, Maine Energy System’s (MESys) ÖkoFEN Pellematic e-max will power all the testing equipment, lights, computers and audio equipment for this year’s Wood Stove Design Challenge on the National Mall. Having recently hit the market in Europe, the Pellematic e-max is designed for “commercial enterprises, hotels and residential complexes,” producing up to 4,000 watts of electricity.

Renewable combined heat and power (CHP) technologies that can supply 100% of heat and electricity to a home or small business come in many forms and are often part of an integrated system with solar panels. The key is matching the electrical needs with the heat needs because 95% of the energy from a pellet CHP unit will be heat and only 5% will be electricity. Thus, hotels or restaurants that need a lot of hot water year round make up many of ÖkoFen's customers for this product.

A smaller version, producing heat and electricity for single family homes, was slated to come to the Wood Stove Design Challenge until organizers asked for the larger version. The residential one has a track record with scores of homes in Europe that use solar panels for electricity in the summer and additional electricity from pellets the winter.   

The Pellematic e-max is designed for a “medium power range”, producing 50-60 kW of thermal power and 4-5 kW of electrical power. To yield these energy outputs, the Pellematic uses ÖkoFEN’s pellet heating system paired with Qnergy’s Stirling engine technology, which has allowed the model to be energy-efficient, low emitting, and a reliable source of heat and power, simultaneously. 

Pairing the Pellematic e-max with solar panels and a smart controller enables the system to use whichever energy source is cheapest at that moment. It plans for upcoming days based on weather forecasts. When its sunny, the system prioritizes the solar panels and can store electricity in a battery for cloudy days. If electricity from the grid is cheapest at night the controller will take electricity from the grid and also store cheap night time electricity to a battery. In the winter, when a lot of heat is needed, the controller will prioritize pellets. The homeowner or business owner does not have to do anything as the system switches between pellets, the sun, the battery or the grid. ÖkoFEN also manufacturers Pellesol solar thermal panels that combined with the pellet boiler can produce hot water for heating and all hot water needs year round.

Alone, the ÖkoFEN boiler provides reliable, economical and efficient heat output when the combustion conditions are kept constant, which makes it a strong base load boiler for commercial  buildings and reliable primary heating source for large households. However, with the attached Qnergy Stirling engine, this powerful heater can be used to produce substantial amounts of electricity
If a home has an electric car, the system
can also switch from pellets to solar to the
grid, depending on which combination of
electric sources is available and cheapest.
as well. When heat from the boiler is transferred to the Qnergy engine, pressure increases and works with the engine’s cooling circuit to create the temperature and pressure differential needed to move the Stirling piston and create electricity.

Developing MESys

Dutch Dresser (middle), Les Otten 
(2d from left) and MESys colleagues
Generating electricity from wood stoves was anything but the projected path for Dutch Dresser. His undergraduate education was in biology and Masters and Doctoral degrees are in science education. Before helping to create MESys in 2007, Dutch had an array of careers in education, computer networking and land development in Maine. Dutch says that he was moved to develop the company when his friend and partner, Les Otten, saw that the region was exporting monumental amounts of money for heating fuel and systems. 

Using the European heating market as an example, Les, Dutch, and Bill Strauss saw that there was a alternative way to run the heating market so that it supports the local economy without fossil fuels. Unlike the northeastern US, the European heating market kept heating dollars in the local economy by selling renewable, locally sourced units. Inspired by the European model, Dutch and Les set out to work with European heating technology to create a local market in Maine, and eventually grew throughout the Northeast.

After getting rejected by many European heating equipment manufacturers who feared working in the litigious America marketplace and one early experience with a problematic product, MESys began working with the Austrian company ÖkoFEN in 2009. Since then, MESys has become the  North American manufacturers for ÖkoFEN.  The bread and butter of Maine Energy Systems are residential pellet boilers that typically cost $8,000 to $15,000 after state incentives in Maine, New Hampshire, New York, Vermont and Massachusetts. The cost of the E-max for small business or multifamily
A comparison of the economics of
four installations of the E-max.
units would be $30,000 or more, but case studies have shown a payback period of 3 - 11 years in Europe.  While the economics of the e-max can make sense in Europe, the demand for the unit is also driven by customers who want to go the extra mile to use renewables, based on their values and the values of their customers.

The barriers of bureaucracy

Different emissions and safety testing protocols have been one of the major challenges to bringing innovative pellet central heating technologies, like the ÖkoFEN e-max, to the market. (European certification testing requirements are not accepted in the US so they have to be certified again in the US.) In Europe, new pellet boilers are being introduced every year and consumers can see these improved products online. But there is no way that an American company can pay to have each model EPA certified in for the US market when sales are still low. Dutch says that the time these tests can take can be “a barrier to innovation.” For Dutch, slow technological transfer in the marketplace is “a system wide issue, not just about boilers or cars, but about absolutely everything.” But it impacts appliances with low sales volumes the most. 

Europe’s best at the National Mall

Maine Energy Systems typically sells to the northeastern US and all of Canada, so the team sees this challenge as an opportunity to expose European boiler technology to a new continent. For Dutch’s vision of global collaboration to make ever more efficient renewable technologies, this challenge means a lot. With such low fossil fuel prices in North America, very few people know about the low carbon heating technologies that are very common in Europe. And the Pellematic e-max is a leading edge technology as it produces heat and electricity that can be paired with solar and other technologies to supply 100% of a home's energy needs.  

Contact the team

Dutch Dresser

Dan Wheeler

Tuesday, July 3, 2018

Meet the teams: A wood stove for off-grid lefties, right-wing preppers, and everyone in between…

This post is the seventh 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 

Roger Lehet on the boat where
he developed his Kimberly™ stove
Like so many other businesses in 2008-2009, Roger Lehet’s 25-year-old brick and mortar wood stove shop was a casualty of America’s Great Recession. When the dust finally settled, the Lehet family of three found themselves living “with nothing and no money” on a boat moored in Puget Sound off the coast of Vashon Island, a fifteen-minute ferry ride from Seattle, Washington. Roger realized that no manufacturer made a wood stove that could fit into the tiny space he carved out of the boat’s cabinetry, so Roger cobbled together the very first prototype for what would later become known as his Kimberly™ stove.

It then occurred to Roger that a thermoelectric system could allow his family to comfortably live off-grid and that his wood stove should provide not only the ability to heat their space, but to also allow his family to cook, bake, heat water, and create electricity. Word traveled quickly and one day a local Vashon resident showed up at the dock, advising Roger to “make it look pretty and get a patent on it.” By the fall of 2012, Unforgettable Fire™ was a newly minted entity and Kimberly™ had passed the rigors of  EPA-CSA and UL testing protocols.

Roger Lehet knew that creating electricity from the heat of a wood stove was possible because he read somewhere that “the Russians did it during World War I.” Roger was also aware that (until the 2018 Wood Stove Design Challenge) no one in the United States was commercially developing this technology, so he gathered a team to explore the possibilities, using the World War I era successes in Russia as a starting point. 
The Kimberly stove

In 2013, the Unforgettable Fire™ team entered Roger Lehet’s Kimberly™ stove in the very first Wood Stove Design Challenge. EPA-CSA certified at 3.2 grams per hour, and weighing only 56 pounds with a tiny firebox of 0.2 cubic feet, Kimberly™ became a darling of the tiny house, RV, and prepper markets, despite selling for nearly $4,000 USD. While many of the 2013 Design Challenge stove entries required a forklift to unload and place inside our tent which was located on the National Mall in Washington, D.C., Roger arrived by taxi, carrying his Kimberly™ stove in his arms. 

Despite having developed Kimberly™ on the deck of a boat, Roger found that the marine community was a harder market to penetrate. Nevertheless, in a matter of years, Lehet sold over 500 Kimberly™ stoves to people living in small and tiny spaces, and to preppers, “many of whom still have not even unpacked their survival stove,” Roger shared with us.

Fueled by his success with his first stove, Kimberly™,  along with the experience of the 2013 Design Challenge, Roger was inspired to create additional wood stoves. Roger’s Katydid™ model debuted in late 2014. EPA-CSA certification testing came in at 1.9 grams per hour, exceeding the EPA emission standards for the year 2020. “I am amazed how much the solid fuel heating industry has cleaned up its act since the unregulated stoves in use when I started as a chimney sweep in 1985,” Roger said. “At one time, we were dumping up to 85 grams per hour into the air. I well remember my lungs stinging as I walked to the bus stop each winter morning as a kid in school.”

Roger’s vision for a multi-use stove has attracted a number of talented people. Among
Team member Vanessa Kelly. Photo by
Dorothy Ainsworth.

them is 
Vanessa Kelly, who showed up on his doorstep in February 2013 and is second in command at Unforgettable Fire™. Vanessa handles everything from web development and online marketing, to sales and technical support. In September 2014, when Roger was on the East Coast as a vendor at a trade show, Vanessa was Roger’s eyes and ears through the EPA-CSA certification process for the Katydid™ wood stove at OMNI Test Lab in Portland, Oregon. Vanessa wrote the accredited owner’s manuals for both the Kimberly™ and Katydid™ models and served as project manager for the EPA-CSA labels. 

When Roger teamed up with the folks at TEGmart, a company that sells thermoelectric components, Roger gained clarity on how thermoelectric modules (TEGs) could better integrate with wood stoves. Today, as Roger explained to us, his team now “creates the stove to match the potential of the TEGs.” This knowledge has driven the Unforgettable Fire™ team to improve the interface between the hot surface of the wood stove and the thermoelectric modules on the stove. 

Ultimately, Roger and his engineering team decided to flip Lehet’s patented technology,
An early prototype of the
TEG system 
found in the Kimberly™ stove, in order to increase the heat in the TEG units. Therefore, the Unforgettable Fire™ Kd3 prototype under development for the 2018 Wood Stove Design Challenge incorporates a gasification chamber on the top of the stove and a re-burn chamber on the bottom. Completely combusted flue gases exit to the right and left sides of the base of the stove where the water-cooled TEG units are installed. 

Roger stated that the resulting flames are “extremely clean”. From past experience, Roger says the stove has produced an easy 75 Watts when paired with solar panels, which he says could run many 9 watt light strips, a water pump, and send a good bit of energy to the batteries. While they have experienced these outputs so far, Roger reports that he expects to test the electrical production from the Kd3 prototype within the next month as the Unforgettable Fire™ team is currently finalizing the engine. As a side note, the design of the electrical component also allows for the addition of solar panels and wind generation.

The challenges that the Unforgettable Fire™ team have encountered over the years in bootstrapping the company from the deck of a boat have taught Roger Lehet to “challenge conventional wisdom.” From the beginning, Roger’s peers have championed high-velocity stoves as the way to get the cleanest burn possible, but Roger went a different route and also found success. Using a low-velocity model, Roger fine-tunes the mixture of wood gas and oxygen as his central method to achieve a clean burn. Lacking important testing equipment to guide him, Roger assesses the cleanliness of the burn solely from the flame’s color. The wood gasification process in the first burn produces flames that are orange, blue, and purple in color. In the re-burning of those gases, Lehet aims to get the whitest flame possible, as flames which appear white in color contain very few particulates. Roger claims that his Kd3 prototype is “able to sustain 850º Fahrenheit in the exhaust manifolds with plenty of radiant and/or convective heat.” When pushed, the Kd3 prototype can sustain up to 1250º Fahrenheit.

A big challenge for very small stove manufacturers like Unforgettable Fire™ is that they cannot afford well-equipped internal test labs to assess particulate matter emissions before taking the stove to an EPA-CSA test lab. Therefore, Roger uses only thermocouples to test his stoves during the design phase. Since the Kd3 prototype does not utilize a manual air control, Roger Lehet hopes to get an emissions exemption from the EPA.

Independent, off-grid energy

Roger competing in the the 2013
Wood Stove Design Challenge
The experience of the Lehet family living on a boat forged Roger’s unique approach to wood stove design. Roger’s goal for the 2018 Wood Stove Design Challenge, and for the stove market in general, is to bring a wood stove and thermoelectric generation system to market under the Unforgettable Fire™ brand, allowing people to live independent of the electrical grid, with little to no compromise to their quality of life.

Contact the team 

Roger Lehet

Vanessa Kelly