What are wood pellets?

Woodco’s boilers use biomass fuels – that is, wood pellets, wood chip and logs. Biomass is a renewable and sustainable fuel, and is plentiful in Ireland. Biomass is becoming more and more popular to reduce reliance on more expensive fossil fuels. It is also a carbon neutral fuel source – trees and other plants such as miscanthus absorb CO2 from the atmosphere, and emit no additional CO2 during combustion. Wood pellets and wood chip are the most common fuels for Biomass Boilers.

Wood Pellets

Wood pellets are made from compressed sawdust, usually waste produced in the wood processing industry (such as sawmills). They are cylindrical in shape, held together by lignin which is naturally occurring in wood. Pellets are uniform in size – around 6mm in diameter and 25mm in length. The pellets are very dry, with less than 10% moisture content.

Pellets can be purchased in bulk, or in individual bags from co-ops, hardware stores or fuel supply stores. Loose pellets are blown into a silo or hopper, or the supplier can deliver bagged pellets on a pallet. Woodco also supplies pellet storage solutions – i.e. hoppers and silos – for residential and commercial applications. It is important that the pellets are kept dry, to keep them intact. These solutions also allow the fuel to be automatically fed to the boiler, for a more hands-off experience.

What do wood pellets cost?

The cost of wood pellets may vary, depending on the supplier. It is often significantly cheaper to buy the pellets in bulk. Shop around to find the best deal – but make sure that they are of an approved quality. Woodco’s pellet boilers require pellets of EN-Plus A1 standard, for optimum efficiency. Using approved fuel will ensure that your boiler works better, for longer. The pellets are very clean, producing only about 0.5% ash in combustion.

The calorific value of wood pellets is around 4.85kWh/kg. This means that one kilogram of pellets will provide 4.85 kilowatt hours of heat energy. By comparison, the calorific value of oil is around 10.18kWh/litre.

Wood Chip

Wood chip boilers are best suited to commercial applications. Woodco’s wood chip boilers begin at 100kW in output. Unlike wood pellets, wood chips are not always uniformly sized and can vary in moisture content. The moisture content is higher overall – usually about 20%. Wood chip is often locally sourced – virgin wood chip can be supplied by Coillte or other local forestry businesses. Alternatively, sawmills or other wood processing plants can supply waste wood chips.

Like wood pellets, dry fuel improves combustion efficiency. However, Woodco’s multifuel boilers are designed to process wet and dry wood chips.

What does wood chip cost?

The cost of wood chip varies even more due to the difference of wood types, quality and moisture content. Because the wood chip can be locally sourced, delivery costs are often very low.

The calorific value of wood chip is around 3.5kWh/kg, or 3,500kWh per tonne. Its ash content is about 1%.

Calorific Value Comparison

Wood Pellets: 4.85kWh/kg
Oil: 10.15kWh/litre
Wood Chip: 3.5kWh/kg

Roughly 2.09 tonnes of wood pellets has the same calorific value as 1,000 litres of oil.

Cost Calculation

To calculate the cost of pellets relative to the cost of oil, simply multiply the cost of x1 tonne of pellets by 2.09. So, for example, if one tonne of pellets costs €240 inc. VAT, 2.09 tonnes will cost €501.60. This would be equivalent to 1,000 litres of oil – which you could expect to cost over €700. That’s a saving of about €200.

If you would like some more information on the various types of Biomass fuels, or on our heating solutions, contact us. Our team would be very happy to help with any queries that you might have. We can also put you in touch with fuel suppliers for quotations.

*Approximate figures above correct at time of publishing.