The efficiency of a wood stove varies from a stove to a stove, and yet it is unclear what wood home heating means. Open fireplaces typically operate at about 10% efficiency, with basic wood stoves having about 30-50% efficiency and modern high performance stoves can reach 90% efficiency.
If the difference between using a 30% efficient and 90% efficient stove using tired wood means that it will burn 3 times as much tree in a year. This waste does not mean too much extra work; cutting, splitting, loading, seasoning and then moving the firewood. Life is simply too short!
What is the Stove Efficiency?
Simply, the efficiency of a wood stove shows that the amount of chemical energy in the fireplace ends in the living room, as opposed to lifting the chimney. The measurement needs to be carefully monitored and in practice done in environmental test laboratories.
The chemical energy stored in wood is actually very easy to find. Most types of wood are referred to BTU by a cable. There are some differences between the different tree species, but basically every kilo of dry wood contains roughly the same amount of energy. In order to find the energy in the stove, measure the wood before it burns.
Calculation of heat transfer to the room is more difficult – you can get a good value by measuring the air temperature at different locations, by airflow airflow, and so on. there are some reliably complex bits of fluid dynamics, but can be done. The efficiency of the stove is there before the percentage of energy transferred to the room compared to the total burned volume.
These data can not be quantified at home, so it is very important to know the nominal efficiency specified by the manufacturer. Generally, older "stoves" are less effective and cheap imports are very low in efficiency, sometimes as low as 20 or 30%.
What influences the efficiency of the wood burning furnace?
These factors fall into two main categories.
- Those that have an effect on firing how well trees are burning
- Those that affect how much heat is transferred from the stove to the room in which it is.
The efficiency of combustion deals with whether the amount of potential energy in the fuel wood actually gets released into the stove. As a general rule, hot fires give greater total combustion and are therefore generally more efficient. We can manipulate this solid stove hall where we insulate the main stove box to hold as much heat as possible. This seems to us to be counter-productive when we try to get the heat out of the stove as much as possible!
The warmer the stove, the more its chemical structure falls down to smaller and smaller molecules as it burns. Of these, the lowest carbon monoxide and hydrogen are. If there is a cool stove then the tree will be much smaller and the larger molecules will not burn properly and will pass the chimney as smoke.
High temperatures are only the first step – to make the most of these small, ready-to-use combustion molecules, additional oxygen needs to be added. The best of the modern stove gives preheated air to a separate part of the fire extinguisher where burning gases burn. This is usually referred to as secondary combustion. If the air is suppressed, these molecules go straight into the chimney without releasing the heat from the stove – both impure and wasteful. I heard that "it blows out the heat with gas flow, but when the tap is running". The best modern stoves carefully control this secondary air, sometimes over the stove operator. This will help the stove to comply with air quality regulations, but the added benefit is to increase efficiency!
Turbulence inside the stove helps mix the gases so that every part of the flame has enough air. Open wood fires are usually "lazy" flames, and the same can be seen in some wood stoves when stopping the air supply. The design of air intakes to create turbulent high-speed airspace results in pleasant, clean combustion.
Given that the furnace needs to be as hot as possible, the question remains how to get enough heat from the stove before the hot gases go up into the chimney. In an existing stove nothing that we usually do about the interior features of the stove can make it possible to control the smoke tubes a little around the indoor spaces and thus gain more heat. Sometimes we can install a heat exchanger on the chimney tube above the stove itself.
The best modern furnaces have incorporated this heat exchanger into the construction to extract as much heat from the gases as they reach the chimney.
External to the stove sometimes gives some improvement to the efficiency of installing a wood stove fan. They increase the flow of air on the surface of the stove, increasing heat transfer to the room. The improvement is small, and since the price tag can be found on a new stove, it's a better investment!
High-efficiency stove is a good investment?
Stoves with 90% -compensated efficiency will buy significantly more for purchase, because interior design is much more complex and the quality of finishing is greater. You can consider this as a good investment if you burn a lot or brick with fire. The cost of firewood is about $ 200 per line (varies considerably depending on the location and type of wood), and upgrading from 30% to 90% can save a lot of grid net during a heating season.
If you buy a stove for a few nights a year, it's probably a cheaper cooker.
Source by Sbobet