Do Bioethanol Fireplaces Produce Heat? The Long And Short Answer

"Do bioethanol fireplaces produce heat?"

It’s one of the most frequently asked questions in our showroom.

The short answer is yes. In fact, ask any one of those showroom visitors and they’ll testify to how quickly a space can warm up once one is lit.

The long answer? Bioethanol fireplaces (or simply ‘ethanol’ fireplaces) feature a very real flickering flame that gives off very real heat.

They’ve become popular additions in environments such as homes, restaurants and hotel lobbies because of their ability to do two things:

1. Elevate the look and feel of a space as an eye-catching ‘fire feature’

2. Create the kind of gentle, cosy ambience no other fire unit can

Bio ethanol fireplaces offer mess-free heating capabilities and are cost-effective compared to traditional fireplaces. Additionally, their ease of installation makes them a major selling point for potential buyers.

But just how ‘hot’ is the heat ethanol fireplace insert create? Let’s explore how they stack up against the more traditional alternatives.

Do Bioethanol Fires Give Off Much Heat?

Ethanol fireplaces are largely regarded as a ‘supplementary’ heat source. Where an open wood-burning fireplace is often relied upon for home heating, bioethanol heaters create a gentler level of heat that keeps you warm and comfortable.

This variation in thermal output in part comes down to the different fuels.

Different Fuels Produce Different Heat Outputs

To understand how much heat the modern fireplace creates, you must first understand how it works.

In short, an environmentally friendly, plant-based fuel called ‘bioethanol’ is ignited with a live flame. The combustion of this fuel then releases heat via convection, in addition to a small amount of steam and an even smaller amount of carbon dioxide.

Wood burning, on the other hand, produces higher levels of heat and carbon dioxide. According to the DCCEEW, this is in addition to:

"a range of pollutants that are harmful to human health, such as particulates, nitrogen oxides, carbon monoxide, volatile organic compounds (VOCs) and polycyclic aromatic hydrocarbons (PAHs)."

Not to mention smoke and ash.

The burning of bioethanol does not – comparably – produce as much heat as wood for a couple of different reasons.

The Different Combustion Characteristics

When it has enough oxygen, wood tends to burn at a higher temperature, while burning bioethanol fuel burns cleanly and evenly with a steady flame, producing minimal byproducts. This is because its ethanol fires produce convective heat in contrast to woodfire’s radiant heat.

(The University of Florida explains that convection is the even transfer of heat via air, whereas radiation transfers it from a hot source directly to people or objects in its way, which is why it feels warmer. Look at the image of the fire table below – cool air is drawn into the bottom of the flame, then hot air is pushed up to the ceiling and around the room. This is convection in action.)

The Different Energy Density 

Wood has a higher physical density than ethanol fuel, which means it burns comparatively slower, releasing more heat over time. In comparison, ethanol tends to evaporate and combust at a faster rate. 

However, the ventless nature of these environmentally friendly fireplaces means heat isn’t lost through a chimney or vent – like it does with wood-burning stove fires – increasing their overall heating efficiency.

How Much Heat Does a Bioethanol Fireplace Give Off?

The bio ethanol fireplace heat output of different fires can be measured in British thermal units (BTUs). For comparison, here are the average per-hour outputs of the most common indoor heating units:

• Wood-burning fireplace: 38,000–80,000 BTUs

• Gas fireplaces: 20,000–48,000 BTUs

• Electric fireplace: 1,000–5,000 BTUs

• Bioethanol fireplace: 5,000–20,000 BTUs

As you can see, ethanol fireplaces certainly pack a punch by way of heat output. And while it may not feel as warm as the heat produced by wood-burning fireplaces, it creates a far more consistent and efficient warmth due to its ventless design and convection heat transfer method.

Compared to gas fireplaces, bioethanol fires units are eco-friendly, require no venting or gas lines, and offer flexible installation options, making them a cleaner and safer alternative.

The same goes with outdoor ethanol fire pits. They won’t replace a log fire like-for-like, but they will produce enough heat to counteract frosty evenings, without also producing smoke, ash and sparks. Just ask Greg.

"A great addition to our deck – we expected it would take the edge off the cool winter air, which it does beautifully, but buyers expecting intense, traditional fire pit kind of heat should consider alternatives."

• Greg H

Do Ethanol Fireplaces Heat a Room?

As a supplementary heating source, the heat ethanol fireplaces produce can certainly increase the temperature of a room, usually by 3–5 degrees. However, this is just a ballpark figure as there are a number of factors that will ultimately determine how hot a room can get:

• Room Size: the smaller the heating area, the more concentrated the heat (though all ethanol burners come with a ‘minimum room’ measurement that determines the smallest possible size a space needs to be to safely house the burner – always refer to the manufacturer’s manual for minimum room size.

• Fireplace Model: the size of the burner and its fuel capacity differs across units, offering a variety of thermal outputs and burner times.

• Insulation: depending on the volume and type of insulation a room has, the presence of it can slow heat flow by absorbing its energy, preventing it from escaping.

• Ventilation: unlike wood fires, ethanol fireplaces don’t require ventilation as they don’t produce smoke or soot, but having some airflow ensures a fresh environment. Too much and you could risk letting the heat out. Imagine an open air setting such as a backyard – the heat from an ethanol fireplace would escape very quickly.

How Large of an Area Will My Ethanol Fireplace Heat?

The table below compares different ethanol burners inserts, outlining the [minimum] room sizes they can effectively heat and for how long.

So, the answer to the question "Do bioethanol fires produce heat?" is absolutely yes. However, they offer a supplementary heat source that tends to ‘hot up’ a space’s aesthetic more than its temperature. 

Their environmentally friendly fuel source, bespoke design and straightforward installation explains ethanol fireplaces’ increasing popularity as a ‘decorative fire’, however their lower heat output ultimately makes them a lacklustre substitute for a traditional wood-burning fireplace (though a stylish one).

See Chama Designs best ethanol fireplace picks for 2024.