Baltpool concludes SM3 quality biomass product study and initiates amendment of the provisions of the Energy Exchange Regulation

At the end of last year, concerns emerged among participants in the biomass fuel market regarding the accuracy of the biomass fuel quality test results. In response, the energy resources exchange operator Baltpool initiated checks on SM3 biomass fuel. A secret buyer conducted tests across five accredited laboratories to assess potential discrepancies in test results. Additional examinations were performed to identify possible variations between two samples taken from the same shipment, acknowledging the heterogeneity of SM3 quality fuel and the automated sampling equipment used.

During the secret buyer’s investigation, samples of SM3 wood chip products were gathered from five different batches, divided into five sub-samples, and sent to five accredited laboratories for analysis. The examination of these 25 sub-samples revealed notable discrepancies in measurements between the laboratories, indicating significant differences in indices recorded:

One laboratory consistently produced the highest results, while another yielded the lowest. The measurements from the remaining laboratories appeared to be fairly uniform. Given these substantial variances in study outcomes, the data collected by Baltpool have been submitted to the National Accreditation Bureau for review as part of an ongoing investigation initiated by Baltpool.

The National Accreditation Bureau, having conducted an evaluative analysis of documents from various accredited laboratories, did not identify any procedural discrepancies and confirmed that the accredited laboratories involved in the inspection comply with the requirements of the standard LST EN ISO/IEC 17025:2018 and are competent to carry out solid fuel testing according to the requirements of normative (standard testing method specifying) documents.

Analysis of Samples in One Laboratory

Baltpool conducted another study to investigate potential differences between samples further. In this instance, two separate samples were taken from the same load—one using automated sampling equipment and the other manually collected by a certified specialist. Both samples were sent to one laboratory for testing. 

This study aimed to validate the hypothesis that SM3 quality fuel exhibits high heterogeneity, which may result in natural quality differences between samples, eliminating potential measurement discrepancies across different laboratories. 

The results demonstrated that, after eliminating the laboratory variable, the ash content indicator could vary by up to 100% among different samples within the same shipment. 

The ash content indicator of two samples formed from the same load of SM3 using different sampling methods, tested in the same laboratory:

Follow-up investigation on SM3 biomass quality results

After confirming the hypothesis that inconsistency in SM3 fuel could lead to differences of up to 100% in ash content values even when testing a single batch within the same laboratory, the operator conducted a follow-up investigation to eliminate possible sampling errors between automated and manual sampling formation.

In this repeat investigation, samples were taken from 17 different machines. Each machine was unloaded in the yard, and two samples were manually collected from each. Each sample was then divided into three subsamples (A1, A2, A3 for the first sample and B1, B2, B3 for the second). Thirty-four subsamples underwent testing, all managed by a certified representative from the SGS laboratory. 

To determine the consistency of results when manually taken from the same batch, the first and second subsamples from each collection were tested in the same laboratories: A1 was compared with B1, A2 with B2, etc. The findings indicated significant differences in ash content values between samples drawn from the same machine, further validating the initial hypothesis.

The ash content indicator of two samples formed from the same load of SM3 using the same sampling method, tested in the same laboratory.

The response from the National Accreditation Bureau regarding the complaint from Baltpool also states that in the case of poorer quality biomass fuel, the ash content increases, and at the same time, the difference between measurement results also increases: “Small inorganic impurities, such as dirt, sand, etc cause the increase in biomass fuel ash content. Such impurities are very fine (<1 mm) compared to the prepared biomass fuel. The distribution of these small non-combustible particles within a sample of prepared biomass fuel can be uneven and difficult to control. Hence, even a small amount of such impurities in a 1 g sample during the ash content test can significantly affect the final ash content measurement result.”

In the absence of objective circumstances that could confirm that the differences in the results of the SM3 tests of the biomass product are due to the different test procedures applied in the different laboratories, and that in practice there are still significant differences in the values of the ash content of the SM3 quality of the biomass as measured in the different accredited laboratories, Baltpool has decided to approach the National Energy Regulatory Council for an urgent amendment of the provisions of the Energy Exchange Regulation governing the application of discounts for exceeding the permitted values of the ash content of delivered biomass. We will inform about the coordination of the draft amendment to the Regulation in a separate communication.