First page of the Generation archive.

Hybrid Residential Solar and Thermoelectric Power Generation

Posted by Earth Stove on June 16, 2017 with No Commentsas , , , , ,
by Ken Adler, Senior Technical Advisor at the Alliance for Green Heat
Some of you may be wondering about thermoelectric wood stoves and why we decided to include them in the 2018 Wood Stove DesignChallenge, which will be held in November 2018 on the Washington Mall.  Our goal of this competition is to support development and commercialization of a revolutionary thermoelectric wood stove that produces electricity equal to 50 percent or more of the winter time output of a residential solar photovoltaic system. By combining a thermoelectric wood stove and a residential solar PV system and home battery, like the TESLA Powerwall, we can support residential and grid-based distributive power goals, and incentivize greater investment in solar power. 
Specifically, thermoelectric wood stoves can help solve the problem of low winter time solar PV output in northern climates, where useful solar radiation is limited to 2 – 4 hours per day.
While a thermoelectric wood stove may sound revolutionary, the technology behind the stove has been used since the 1980s in oil and gas field operations, where methane gas provides a low-cost source of heat to power the thermoelectric generator. Wood stoves, like waste methane gas, can provide a free source of heat for the thermoelectric generator.
Alphabet Energy Thermoelectric Generator
Thermoelectric generators are like solar panels, however, instead of turning light into electricity they turn heat into electricity. To generate electricity, one side of a thermoelectric module is heated by the wood stove while the other side is cooled with either an air or water-cooled heat sink. For applications above 100-watts, water-cooled heat sinks are the most common approach because of their ability to extract greater amounts of heat from the thermoelectric module.
60-Watt Water Cooled Thermoelectric Generator
In northern climates like New England, Canada and northern Europe, low winter time solar radiation increases the cost and reduces the efficiency of solar PV systems, and the cost-effectiveness of battery storage systems like the Tesla Powerwall.  According to NREL, solar radiation in northern areas like Vermont peaks at 6.0kWh/m2 in June and declines to 1.7kWh/m2 in December. This means that an average 4,000-watt residential solar system will go from producing 571kWh in June to 191kWh in December–a 66% reduction is solar power output.  This project will demonstrate how a thermoelectric wood stove can cost-effectively supplement a solar PV system.
Building on our experience from 3 previous Design Challenges, we will work with wood stove manufacturers, universities and others to build and test 100 to 200-watt thermoelectric wood stoves that could effectively increase by 50% the winter time output of a 4,000-watt residential solar PV system.   

Thermoelectric generators are currently sold as accessories for wood stoves; however, these accessories are limited in size and efficiency. By integrating a thermoelectric generator into a wood stove we can achieve far greater power output, efficiency, and lower cost. For example, a wood stove with a 150 to 200-watt thermoelectric generator operating 20 hours per day could generate 93 to 124kWh of electricity per month, which compares favorably with the December solar PV output of 191kWh in Vermont.

Russian Thermoelectric Wood Stove 
(not certified for sale in the U.S.)
There are several reasons why now is the time to consider thermoelectric wood stoves. First, the price of the thermoelectric modules, which are a component of the TEG, has dropped substantially because they are now being mass produced in China.[1] Second, the EPA’s recent wood stove NSPS regulation is helping to make new wood stoves cleaner and more efficient and, coupled with cordwood testing and automated features, a new generation of cleaner stoves could also generate electricity. Third, thermoelectric wood stoves can produce electricity up to 24 hours per day eliminating load management concerns common with solar and wind power. Lastly, the stoves are powered by local wood supplies, making their fuel low carbon and locally sourced.
The 2018 competition on the Mall will demonstrate the role thermoelectric wood stoves can play in promoting solar power, energy storage systems and biomass energy, while also reducing energy costs, supporting climate change goals, and increasing distributive power.   



[1]The cost of a thermoelectric module has fallen below $ 2 per watt (uninstalled), compared with $ 3.50 per watt for solar panels (installed).

Heated Up!

Fourth Wood Stove Competition to focus on automation and electricity generation

Posted by Earth Stove on February 26, 2017 with No Commentsas , , , , , , ,
Today, the Alliance for Green Heat announced the fourth Wood Stove Design Challenge, returning to the National Mall in Washington, DC in November 2018. 
The 2018 event will be free and open to the public and includes rigorous testing of the next generation of technology that can make wood stoves consistently cleaner, more efficient, easier to use and, like solar energy, a renewable source of electricity.
The fourth Wood Stove Design Challenge is modeled after the Department of Energy’s (DOE’s) Solar Decathlon, a competition between teams from universities worldwide to design more efficient and cheaper residential solar power.  Like the Solar Decathlon, the Wood Stove Challenge also attracts teams from around the world and focuses energy and resources on innovation and improved performance.  The stove competitions have been in partnership with the DOE Brookhaven National Lab, the New York State Energy Research and Development Administration (NYSERDA), the US Forest Service and others, the Osprey Foundation, among others. 
Participants will compete in two events:  One is to automate the wood stove with 21stcentury technology like sensors and WIFI-enabled controls that improve combustion efficiency, reduce air pollution and improve ease of use.   The second competition will focus on thermoelectric wood stoves that generate electricity to power lights, cell phones, and WIFI-enabled controls. Thermoelectric generators are similar to solar PV systems except they turn heat instead of light into electricity.  When integrated with a residential solar PV system, a thermoelectric wood stove and battery power system, like the TESLA Powerwall, could effectively double the wintertime output of solar PV system in areas like northern United States, Canada and northern Europe.
Wood stoves are still used by 30 – 60% of homes in hundreds of rural and suburban counties around the country.  Yet, the technology revolution that has swept household appliances in the last 20 years has by-passed wood stove technology. 

Teams in the 2018 stove challenge will be competing for up to $ 50,000 in prizes.  The teams and exhibitors will also have a chance to showcase new technology on the National Mall just blocks away from the Department of Energy, the US Department of Agriculture and the Environmental Protection Agency. 
“This is a chance for students, back yard inventors, and wood stove manufacturers to re-invent this age-old technology for today’s environmentally conscious and time-conscious consumer,” said John Ackerly, founder of the Wood Stove Competition and President of the Alliance for Green Heat.  “An affordable, smart wood stove is achievable and could help millions of families reduce their reliance on gas and oil while significantly reducing  pollution,” Ackerly added.
“This is the first Wood Stove Challenge to promote wood stoves that generate electricity to power everything from a cell phone to an entire home.  Thermoelectric wood stoves, when integrated with solar PV systems and home batteries like the TESLA Powerwall, have the potential to make solar energy more affordable, reduce air pollution, and pave the way for a more sustainable energy future, “according to Ken Adler, Senior Technology Advisor at the Alliance for Green Heat and formerly with the U.S. EPA.
Previous Stove Design Challenges brought innovative stoves and a diverse array of stove and energy experts together on the National Mall in 2013, Brookhaven National Lab in 2014 and 2016.
Further details about participating and competing in this competition will be available late March, 2017. For more information about the  2018 competition, contact John Ackerly at jackery@forgreenheat.org. For inquiries specific to the electricity production category, contact Ken Adler at kadler@forgreenheat.org.
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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 and hosts international stove design competitions to accelerate innovative stove technology.  Founded in Maryland in 2009, the Alliance is an independent non-profit organization and is tax-exempt under section 501c3 of the tax code.

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Media Advisory: Wooden Stove Decathlon to Encourage New Wave of Renewable Energy Generation

Posted by Earth Stove on October 17, 2013 with No Commentsas , , , , , , , , ,

MEDIA ADVISORY for November fifteen-19, 2013 Get in touch with:&nbsp Patricia Brooks, patricia.brooks@matchmapmedia.com, (202) 351-1757 The Heat is On: Wood Stove Decathlon Held on Countrywide Shopping mall to Encourage a New Wave of Renewable Energy Innovation Modern day wooden stove systems provide a lower-emission, higher performance, and affordable remedy to assembly America’s house heating calls […]