A Rocket Heater by Liberator LLC is by far one of the most economical to operate wood stoves on the market today. Its design is a direct descendant of rocket mass heating technology (see "Rocket Heaters History" above) and it shows!
A Rocket Heater uses only one fourth the wood a typical wood stove uses and does so by burning tree limbs and large sticks, while being one of the cleanest burning wood stoves in existence.
This high efficiency is accomplished by maximizing draft and the oxygen supply, effectively utilizing similar principles that large scale metallurgical blast forges use to create steel and other industrial products. Most conventional wood stoves use either a catalytic combustor or limit the air supply to re-ignite the gases later in the burn cycle. These conventional systems are hard to maintain and are overly complex and very expensive.
But these conventional approaches are completely circumvented by the Liberator Rocket Heater, which also uses a second principle of efficiency that most all other designs blatantly ignore, which is maximizing the thermodynamics of heat transfer. After all, a good clean burn is completely irrelevant if all the heat goes straight up the chimney and into the sky.
Convection, conduction, and radiation (infrared) are the three ways heat transfers into a room. Heat is most efficiently 'pumped' out of the stove (via convection, conduction, and radiation) by 1) maximizing the volume of the stove which slows the gases soon to be exhausted, and 2) by maximizing the surface area of the stove where the exhaust gases will come into contact. In addition, the geometric concept of having an internal chimney maximizes the draft, thus creating a 'forge' effect as mentioned earlier, and only permits gases that are substantially cooler than the top to fall to the bottom of the wood stove and vent into the chimney, which is attached to the bottom of the stove.
All of this 'thinking out of the box wood stove engineering' means that this Rocket Heater will often reach temperatures as high as 300 degrees Fahrenheit (150 degrees Celsius) in less than ten minutes from start. It will reach its optimal 'idle' temperature of 650 degrees Fahrenheit in about half an hour. If you put seasoned hardwood in the heater, it can reach temperatures as high as 750 degrees Fahrenheit on the top plate. All these high temperatures are maintained throughout the heater, yet the stove pipe remains well under 300 degrees (measured 6" inches back) on average.
And it does this with nothing more than sticks, branches, and split staves less than 2" inches in diameter. Waste wood such as old 2 x 4's (split down further), blocks, scraps, and other waste products that usually get overlooked are perfect fuel for the Rocket Heater!
You can use this heater for over an hour and 15 minutes without refueling if you use hardwood and around 45 minutes with branches and softwood. One fourth of an 18" inch long log split into staves can provide this extreme amount of heat for well over a few hours. Starting a fire in the Liberator Rocket Heater takes no more than 30 seconds with some practice (please refer to our user manual).
Chainsaws (which are gasoline powered thus partially negating the benefits of heating with wood) are the number one tool involved in accidents on the job in America, and axes aren't much safer. Reducing the time behind these tools reduces the chances of losing a finger. With the Liberator Rocket Heater you're not just helping the environment and being more independent, you're reducing the amount of time and energy spent in felling trees, bucking wood, and splitting logs.
Even if you use natural gas for heating, the average American household uses over 183,000 cubic feet of natural gas per year, which amounts to an annual gas bill of over $800. If you could save even half of that per year, the Liberator Rocket Heater will have paid for itself in just a few years, and after that it's all savings. If you're using electric, fuel oil, or propane, you know very well that you can't afford NOT to have this heater!
Shown Below is a video of an early prototype.
Shown Upper Left is a photo of our finalized version with flue pipe properly installed. T-connectors can be used in place of elbows to make cleaning and maintenance easier and more convenient.
Shown Lower Left is the heater's firebox while running.