Resource Centre article

G30 wood chip explained.

A practical guide to G30 wood chip, commercial biomass fuel specification and why particle size matters for boiler reliability.

Close-up of G30 commercial wood chip showing particle size

Fuel specification

What is G30 wood chip?

G30 is a commonly used term in the biomass fuel market to describe a relatively small, consistent wood chip grade used in many commercial biomass boiler systems.

Different standards and boiler manufacturers may describe chip size and fuel requirements differently, so the important point is not the label alone. The fuel must suit the boiler, fuel-feed system and storage arrangement.

Particle size

Why particle size matters.

A biomass boiler does not simply need wood chip. It needs fuel that can move through the store, extraction system, augers or conveyors and combustion chamber without avoidable problems.

Oversized chip can bridge or block

Excessive fines can affect feeding and combustion

Inconsistent chip can make boiler control less predictable

The right chip grade supports smoother operation

Fuel should match the boiler manufacturer's requirements

Complete specification

Particle size is only one part of the specification.

G30 describes the physical size profile of the chip, but fuel performance also depends on moisture content, contamination, consistency, ash behaviour, storage and delivery planning.

McCauley Wood Fuels' core commercial product is dry G30 wood chip, generally supplied at approximately 25% moisture content, subject to the agreed customer specification.

Read about fuel quality

Boiler suitability

Is G30 suitable for every biomass boiler?

No single chip grade suits every biomass boiler. Some systems require a particular particle-size range, moisture level or fuel quality standard. Before changing supplier or specification, the boiler manual, installer, service provider and existing operating experience should be reviewed.

Commercial applications

Where G30 wood chip is commonly used.

Suitability depends on the boiler, storage arrangement, delivery access and agreed fuel specification.

Buying checklist

What to check before buying G30 wood chip.

Boiler manufacturer's fuel specification

Acceptable particle-size range

Target moisture content

Fuel-store design

Extraction and feed system type

Delivery access

Annual fuel requirement

Current fuel issues

Storage ventilation and drainage

Supplier quality process

Operational risk

What happens when chip does not suit the boiler?

Poorly matched or inconsistent wood chip can contribute to handling issues, bridging, blockages, combustion instability, higher maintenance demand and avoidable downtime.

Fuel is not always the only cause of boiler problems, but it is one of the first practical factors worth checking when reliability is poor.

Wood chip drying and processing equipment supporting specification-led fuel supply

McCauley Wood Fuels approach

Specification-led supply.

McCauley Wood Fuels treats commercial wood chip as part of the heat system. Before agreeing supply, the company works to understand the boiler, fuel store, site access, annual demand and operating requirements.

FAQ

G30 wood chip FAQs.

Is G30 wood chip the same as garden chip?

No. G30 wood chip for biomass boilers is a commercial fuel product. It is not decorative garden chip, mulch or bagged landscaping material.

Is drier always better?

Not necessarily. The correct fuel is the fuel that suits the boiler and handling system. Consistency and suitability are usually more important than chasing the lowest possible moisture content.

Can I use G30 chip in any biomass boiler?

Not automatically. The boiler manufacturer's specification and the fuel-feed system should be checked before agreeing supply.

Can McCauley Wood Fuels advise on suitability?

Yes. McCauley Wood Fuels can discuss your boiler, fuel store, current fuel experience and operating requirements.

Fuel specification

Need the right wood chip specification for your boiler?

Speak with McCauley Wood Fuels about dry G30 wood chip, moisture content, boiler suitability and long-term supply planning.