Quality biomass boilers deserve quality wood chip

If you’re shovelling tonnes of wood chip into your biomass boiler but getting nothing like the projected heat – and RHI payments – back out, the chances are it’s a problem with the quality of your chip.

Biomass boilers are like people – they love consistency

We’ve been installing and servicing biomass boilers for years, and the majority of our call outs are down to poor fuel. Consistently feed yours with quality chip and it will reward you with consistently efficient heat output and consistently optimal RHI payments. Problems start when you cut corners with your wood chip…

What should you look for in a good quality wood chip?

  • Moisture content of between 25% and 35%, depending on your boiler.
  • Less than 1% ash yield.
  • Freshly cut timber – while the quality of clean recycled wood can be acceptable, freshly cut virgin timber has a higher calorific value and burns for longer.
  • Small, consistently sized chunks of wood, not flakes or shards – chunky wood chip burns for longer, while flakes and shards can jam your augur and cause blockages.

We test every load before it reaches you

Quality lies at the heart of everything we do. Before your delivery leaves our covered facility, it’s tested in our onsite lab. If it doesn’t meet the following standards, it doesn’t leave the building:

  • Moisture content of between 25% and 30% – though if your boiler requires something different, we can of course oblige.
  • Consistent particle distribution – we typically supply G30 or G60 chip (with a maximum sectional area of 30mm or 60mm), depending on your requirements.

Additionally, we only supply chip from clean virgin timber, ethically sourced from FSC woodlands and with a low ash content. At the moment, we are undergoing auditing to achieve Woodsure Quality Assurance status – watch this space…

Low cost, high quality wood chip from Lime-CircleAll wood chip is not the same

While it can be tempting to go for cheap wood chip, it can cause problems in the long run. If a wood chip supplier uses low grade wood or mixes chip with arbicultural waste, the fuel’s calorific value is reduced, meaning you get less burn for your buck.

And as well as being inefficient, poor quality fuel can lead to breakdown or even total loss. RHI payments are linked to the boiler itself, so if yours dies and needs replacing, your RHI contract will start again on what could well be a lower tariff.

Too much moisture can cause early heat exchanger and water jacket damage. Too little, and the chip burns too fast. Too much ash leads to carbon slag build up, which reduces performance and efficiency. As with most things in life, you get out what you put in…