Wood Stove Efficiency – Concept, Benefits & Components

This article will be discussing all things relating to wood stove efficiency.

For a long time, heating and combustion efficiency has been at the forefront of considerations made by homeowners before buying a wood stove. Efficiency has to do with the heat output obtained from wood fuel.

If you’re seeking answers to enable you to make a purchase decision, then this article will be a great read.

Understanding The Efficiency Of Wood-Burning Stoves

When discussing efficiency for wood stoves, two areas are often focused on.

They include combustion efficiency and overall efficiency. These key areas of efficiency define how useful a wood stove is in converting fuels into heat through combustive action.

  • Combustion Efficiency

Combustion efficiency mostly measured in percentages defines how much heat is produced by a wood fuel when combusted. This is solely restricted to the amount of heat generated and not by the transfer rate of such heat to the home.

  • Overall Efficiency

As the name implies, overall efficiency covers the entire combustive action and heat transfer.

Here, it represents the percentage of heat that gets transferred to a given space when fuel loads are combusted.

To properly calculate overall efficiency, it’s necessary to consider contributory factors like proper installation of the wood stove, wood moisture levels, and the soundness of the woodstove appliance.

Be Wary of Unspecified Efficiency Levels

More often than not, the sale of wood stove products may be done with little disclosure on specified efficiency levels.

In other words, the emphasis is usually more on combustion efficiency. In most cases, the combustion efficiency is higher than the overall efficiency.

The variance in efficiency levels between the two may range from 10 to 20%.

So, when a brochure advertises a wood stove product to have an “80% efficiency level” with no specification, it may actually be referring to the combustion efficiency and not the combustion efficiency.

This can be frustrating if you want to know the specific efficiency ratings. Thankfully, there’s a way out! Consider visiting the Environmental Protection Agency (EPA’s) Certified Wood Stove Database.

Information on your device model may be available on such a database.

Efficiency Of Wood Stove Compared To Wood Fireplace

Here is a general comparison of wood stove and fireplace.

Before wood stoves became a thing, wood fireplaces had been the most common household heating provisions.

Wood stoves were designed to counter or correct the common flaws wood fireplaces have. The result was a significant increase in efficiency levels.

Wood stoves are known to have efficiency levels of around 60% to 90%. This is a major jump or improvement when compared with open wood fireplaces having efficiency levels of around 10% to 20%.

With open wood fireplaces, it takes longer for a home to be heated.

As a matter of fact, you may sometimes experience negative heating efficiencies for homes with poor insulation. As such there’s wastage of fuel for open fireplaces among other disadvantages.

Wood stoves correct all of those inadequacies by burning fuels much more efficiently.

Picking the Right Wood Stove For Energy Efficiency

As mentioned earlier, wood stoves come with varying efficiency levels.

Apart from that, reliable products will always have EPA’s seal of certification. One of the ways to pick the right wood stove is by referring to the EPA’s “list of certified appliances.”

Before making a purchase take a look at the back of the woodstove for a metal tag. This tag holds key information necessary to help with your search.

In a situation where you have an old wood stove (especially those manufactured before 1990), consider having it replaced with a more efficient model.

Benefits Of Efficient Wood Burning Stoves

There are about four main benefits attached to using high-efficiency wood stoves.

First, your home gets heated more efficiently. An added benefit includes savings on fuel. Unlike open fireplaces, there’s fuel waste. This saves you money.

What more? The health benefits are enormous! With efficient combustion, there’s less exposure to harmful gases.

This is of great benefit as your air is much cleaner compared to open fireplaces.

Enhancing Wood Stove Efficiency

Apart from the basic design of wood stoves, there are ways to increase efficiency levels. This involves using wood fuels with the most energy per cord. Not all firewood posses the same combustion efficiency.

In terms of combustion efficiency, you’re also looking at the hardest which translates to long combustion times.

Some of the best woods to consider as fuel include ironwood, rock elm, hickory, oak, sugar maple, beech, yellow birch, and ash. The denser the wood, the longer it burns and the greater the efficiency levels.

Wood Moisture Content and Combustion Efficiency

It’s important to carefully pick the wood type to use as fuel for your wood stove. Seasoned or dry wood is the best to use for fuel. Those with a great deal of moisture content do little to add to combustion efficiency.

One of the things you’ll observe with unseasoned or wet wood is the production of excessive smoke.

This situation creates a loss in heat, thus making your wood stove less efficient. Some little action on your part can go a long way to ensure the fuel used is properly seasoned or dried.

To promote faster drying, consider splitting wood logs into sizes of around 6 inches (or less) in diameter. To store such wood, stack them up, with the split sides facing down. Ensure they don’t lie directly on the ground.

By covering the stack up, you’re preventing direct exposure to snow and rainfall.

The length of time such wood is stored is also important. Consider storing for at least a period of 12 months for hardwood. Storage time can be less for softwood.

Wood Stove Installation

No matter the efficiency levels of a wood stove, it won’t do much when it’s not installed properly. It’s necessary to have it properly installed by hiring the services of a professional.

Reputable wood stove dealers may give out contacts of professional technicians to handle the installation process. Consider making the necessary inquiries and only using EPA-certified wood stoves.

We’ve seen that there are several factors tied to wood stove efficiency. These and more have been discussed above.

As always, never allow any professionals to handle your wood stove installations.

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