The benefits of burning wood

Firewood sales have increased by 20% over the past couple of years, as more Costa home owners choose this cheap, ecological and aesthetically attractive way of heating their homes.

Open fireplaces are rarely seen nowadays, as homeowners much prefer wood burning or pellet stoves, as they have an 80% efficiency rating compared to an open fireplace which has a maximum efficiency rating of 25%.

Other benefits of burning wood are:

Unlike the burning of fossil fuels, burning firewood releases no more greenhouse gases (carbon dioxide) than would be produced were the wood be left to simply rot on the forest floor. Naturally burning a renewable source grown from the earth itself will not pollute the earth.

Unlike gas, oil and coal fuel, wood can be readily and quickly replaced by the planting of new trees.

Learn to spot the difference between unseasoned and seasoned wood. You can check the moisture reading of the wood with a moisture meter that is extremely simple to use.

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These logs have about a 45% water content and are much heavier to lift. When burning unseasoned firewood more energy is used to burn the wood as the moisture content needs to evaporate up the chimney. This means you will have a cooler fire. As the wet wood or green wood (as it is sometimes called) is burnt, it will cause a build-up of creosote, a black sticky tar substance that clogs up your chimney, pollutes the environment and causes the glass in your fire to turn black. This substance is the main cause of chimney fires.

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To minimise the risk of this, use wood that is a light yellow colour with bark peeling off it and has cracks in the ingrain. This type of wood is light to carry and when knocked together has a hollow thud sound. Dry wood will burn hot – heating up the flue, creating a fast draw, and shooting the smaller amount of vapours out of the chimney before they get a chance to condense.

Save money by seasoning your own wood

There are three main stages of seasoning or drying out your own wood which include:

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Often referred to as 'green wood' this is freshly felled wood which can have a moisture content of up to 50% or more.

It is relatively easy to differentiate between any other types of wood because it is lighter in colour, the bark will still be attached and there will be few if any cracks (in many cases it will feel moist to touch). The logs will also be heavier to lift.

If you are able to obtain fresh felled wood this is where you have the potential to save most money.

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The process of air drying wood is relatively simple and can reduce the moisture content from 50% down to as low as 25%. Wood can hold water both within the cells and the cell walls which is why it is so moist when first felled.

The best way to air dry wood is to place it in an area which is exposed to the elements but ensure that it is placed ideally on pallets to make sure no moisture is absorbed from the ground.

When you cover it up to prevent it getting wet make sure there is still significant ventilation otherwise it will rot instead of drying.

The final stage of drying out your wood is to bring it into the house just a couple of days before it will be required. This will bring the moisture content down to around 20% which is ideal for the modern day woodburning stove.

While you should monitor the moisture content with a moisture meter (cheap to buy) through all of the stages, the most important reading is the final house dry reading which should be no greater than 20%.

The difference between hardwood and softwood

Hardwood is denser which means it burns relatively slowly and for longer, and also gives off a higher calorific value, keeping your room warmer and you will not have to get up to fill your stove as often.

Hardwood should be seasoned (left to dry) for at least one year if not two, and it takes up less storage space per tonne than softwood. Examples of hardwood: oak, beech, ash.

Softwood is less dense meaning that it will burn quicker, create less heat and be ultimately more expensive to use, it burns twice as quickly as hardwood and you will be spending more money to get the same amount of heat that you would get with hardwood. Soft wood: most fruit trees and conifers.

Types of wood to consider

Various types of wood are more appropriate for wood-burning stoves than others. Some of the types of wood available in Spain to consider include:

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This is considered by the Spanish as the best firewood, it is high density, slow burning and long lasting. It produces a short bluish flame and has a high calorific rating.

■ As the natural moisture level of ash wood is around 66% it does take some time to season to a moisture level of around 20%.

■ This is a hardwood that creates a hot, long lasting fire and produces only a small amount of ashes, much like oak. However, almond seems to season or dry out a little faster than oak.

■ Oak wood is probably one of the best-known types of wood and is commonly used in Spain for wine barrels. This hardwood is relatively dense and it burns relatively slowly but emits significant heat.

■ It's one of the best firewood types. This dense hardwood burns hot and clean without a lot of sparks. ■ This wood is known for burning very hot. The oils in the wood along with the ability to create an intense flame has led some wood stove distributors to recommend not burning the wood.

Others who live in a region where eucalyptus is prevalent have used the firewood for years, without any issues and love it. To avoid creating too much heat, mix the eucalyptus in with other firewood types. Or start off your stove with eucalyptus and then use oak.

Eucalyptus needs to be left 2 or more years to dry out. Attempting to burn the wood before will have disappointing results.

■ This hardwood burns longer than most types of wood due to the density, it comes from the annual pruning of olive trees.

It also gives out more flames than other woods as well as having a high calorific value, so it is a favourite for wood burning stoves.

The average price of firewood in Spain ranges between €0.15 and €0.19 per kilo. The recommended types of wood include oak, ash and beech, with holly oak being the most expensive.

Conclusion

As with any machine the higher the quality fuel, the greater the efficiency and the output.

It is no different for your modern day wood-burning stove, if you use poor quality or over moist wood you will get nowhere near the published efficiency ratings of your stove.

Trying to save money buying substandard wood will turn out to be more expensive in the long term and potentially damaging to your stove.

However, one of the easiest ways to see whether your stove is burning at optimal levels is to take a look at the smoke coming out of your chimney.

A relatively small release of smoke through your chimney indicates that the vast majority of gases created in the combustion process have been burnt off within your stove.

However, if your chimney is emitting a thick plume of smoke this indicates your stove is not working at optimal levels and you will need to either improve the quality of your firewood or adjust the airflow appropriately.

In order to prevent your chimney or stove pipe catching fire due to excess creosote, you should throughly clean your wood burning stove chimney at least once a year, and inspect it at least once each month.