1. Brief Introduction of Pellet Fuel & Wood Pellets

Pellet fuel, made from compressed organic matter or biomass materials, is a renewable and clean-burning heating alternative. In general, there are five types of biomass sources, i.e. energy crops, virgin wood, agricultural residues, food waste, industrial waste and the co-products (see Pellet Fuel in Wikipedia). The common materials for biomass pellets include straw, rice husk, corn stover, sawdust, wood chips, wood shavings, palm wastes (like empty fruit bunches and palm kernel shells), coconut shells, bagasse, grass, alfalfa, sunflower husk, etc.

Wood pellet, the most common pellet fuel, is generally made from compacted sawdust, wastes from milling of lumber and manufacture of wood products (also see Pellet Fuel in Wikipedia). Typically, wood pellets are for industrial use and residential/home use. Here the latter one shall be elaborated.

2. Advantages of Using Wood Pellets for Residential Heating

While being used as fuel, wood logs need to be chopped. Besides, they are cumbersome to move and store. Also, they create smoke which is not friendly to the environment. However, wood pellets, compared to wood logs, are tightly compacted, and are with less moisture content, higher density and uniform shape. That means they provide more thermal value; they can be handled easily; more fuels can be transported and stored in a given space; they provide remarkable consistency and burn efficiency; and they produce a fraction of particulate emissions.

If the materials for pellet fuel are easily available for you, it would be a wise choice to make your own pellets. By doing this, forestry residues (as well as agricultural residues) can be fully utilized; you can save a lot on heating cost; and you are free to use pellets at any time without entering into a pellet store.  

3. Market Distribution (User Distribution)

Pellet fuel has been popular for residential use throughout the world, especially in North America and European countries.

Pellet stove continues to be a big hit. The warmth wood pellets provide and the rising of fossil fuel cost make many households in the U.S. install a pellet stove, which indicates that more and more people are looking for pellets as heating source. According to Pellet Fuels Institute, there is a considerate number of families in the U.S. using wood pellets for heat in stand-alone stoves, pellet stove inserts, furnaces and boilers. In addition, pellet fuel is used for heating in such large-scale facilities as schools. EU countries such as Germany, Austria, Poland, Finland, Portugal and Spain took an important position especially in the segment of high quality pellets for residential heating. However, unlike most countries, primarily using wood pellets in electrical power generators and co-fire with coal, Italian used wood pellets exclusively for heat in homes, commercial enterprises (such as hotels) and institutions (like hospitals and schools). Using wood pellets for residential heating has experienced a rapid growth since wood pellets have been introduced to the market as heating fuel. The trends are also the result of some support measures, promoting small-scaled users like house owners, and medium-sized residential buildings to install biomass pellets heating systems.

Pellet stove is truly an attractive heating appliance for people in cold winter.

4. Pellet Fuel Appliances

As we know, wood pellets can be used for home heating and cooking. In this way, one should get pellet fuel burning appliances such as pellet stove to make wood pellets into use.

Wood-fueled stoves create smoke, so they require a chimney and flue. Before using the stoves at the beginning of each heating season, you should make your stove and chimney inspected by a professional. Wood pellet stoves rely on an electric blower to spread heat, so they must be installed near an outlet.

4.1 Types of wood pellet stove

There are various types of pellet appliances used for pellet heating, including stand-alone pellet stove and pellet stove insert, both of which adopt bottom-feeding or top-feeding method.

The stand-alone pellet stove, which does not attach to walls or a particular position, can be placed anywhere in one’s home. During operation, this kind of stove consumes little electricity. To heat multiple rooms, fans or blowers shall be used together with the stove.

A pellet stove insert is a stove inserted into an existing masonry or prefabricated wood fireplace. Most pellet inserts are bottom-fed models.

Also, there is another type of pellet burning appliance, i.e. pellet basket, which allows families to heat their home by burning pellets with their existing stoves and fireplaces. In the following, a typical pellet stove shall be introduced.   

4.2 Components
In general case, a pellet stove is composed of a hopper, an auger system, two blower fans (for combustion and convection), a firebox, several safety devices (vacuum switch, heat sensor), and a controller.

4.3 How does a pellet appliance work?

The pellet stove begins working by electric starter. When the stove is lunched, pellets are fed into the hopper, which is located on the top or the bottom of the stove. Then the motorized auger delivers the pellets from the hopper into the combustion chamber (or firebox). The burn pot in the firebox is then ignited, after which, the process of burning comes. There is also an ash pot to store the ashes after burning. In the back of the stove, there is a narrow pipe vented into an existing chimney or connected to the outside through a small hole.

The heated air runs through a heat exchanger located in the combustion chamber. The blower fan for convection is to delivery heat into the whole space through convection.

Notes:
a. There is a sensor or timer for the auger, which is to control the amount of pellets fed into the combustion chamber.
b. Also, the stove’s temperature depends on the auger’s speed.
c. The whole stove is controlled by a thermostat, by which, the temperature can be adjusted.
d. If you want to use one stove to heat multiple rooms, specially designed fans should be installed in walls so as to transfer the heat into other rooms.

4.4 What are the benefits of using pellet stove?

a. Pellet stove is an attractive home appliance.
It can make your home warm consuming less electricity. That would be much better if you have a small pellet press and biomass materials are easily available for you. So, with a small pellet maker and a pellet stove, you can supply heating source for yourself.
b. Wood pellet stove is more friendly to environment.
Compared to traditional fireplaces, pellet stove emits fewer pollutants. There is less smoke generated, which lessens the smell in your home. Pellets create considerably less ash than firewood. Besides, according to environmental protection agency, pellet stove has lower particulate emissions due to their high burn efficiency and high density.
c. Automatic operation can be realized by a pellet stove.
The pellet stove may need to be loaded only once a day, depending on what size hopper your stove has. Thus, you needn’t to feed the stove now and then. Instead, you have spare time to do other things.

In one word, that would be perfect for you in cold winter, if you have a small pellet making machine, and the biomass materials are available for you, plus you have bought a pellet stove.