General information

In 1997 ECN decided to design a database of biomass compositions for internal use. The database contained data from literature, from the TU Wien database, and from ECN biomass analyses. In 1998 the information was made available to third parties and the number of data records was increased. In 1999, the database became accessible through the Phyllis website. Since then, both the functionality of the website and the content of the database have grown.

From 2007, the BIODAT database was developed within the European PHYDADES project. BIODAT is restricted to data from standard analysis methods. In 2012, BIODAT became a subset of Phyllis and the Phyllis website was adapted accordingly. In the future, the BIODAT subset will be the main growth area of the Phyllis database.


The materials are divided into groups and subgroups according to the ECN Phyllis classification, based on a mixture of plant physiology and practical considerations. The materials have also been classified according to the NTA 8003 classification (version December 2008), the result of the "Classification of Biomass" project initiated by Novem. Both schemes can be used to select materials, but at present the NTA 8003 classification is available in Dutch only. The BIODAT subset of data is also classified according to CEN/TS 14961.

The database does contain materials for which there is no valid code within a classification scheme. These materials are given non-standard codes “other” or are hidden.

Database content

Each data record with a unique ID-number shows information (if available) on:

For each data record the source (reference) is indicated.

In the database three types of weight units are used:

How to use Phyllis

Phyllis can be used to get all accessible information on a single sample or to get average values for groups or subgroups in any desired combination.

ECN also offers selections tailored to your wishes at a reasonable fee. Address for information.

Finding and browsing biomass samples

After selecting a classification scheme, you will see an interactive tree containing the samples in the database, classified into groups according to the chosen scheme. You can click the name of a group to open it and see the subgroups or samples it contains.

A search field is available above the classification tree. You can use this to search for names of samples, classification groups, and sample IDs. The tree will highlight the results when the search is complete.

When you click on a sample, its details and the measured values that have been recorded in the database are shown on the right. The values are organized into groups, each of which can be hidden or shown by clicking the header. When possible, dry values are automatically converted to daf (dry & ash free) and ar (as received) values for certain properties, in which case all three values are shown side-by-side.

Calculating averages

The same page that allows you to browse the classifications and view details of individual samples, also allows you to calculate average values of arbitrary sets of samples. To do this, first create a selection of biomass samples by using the checkboxes in the tree. You can select and deselect individual samples as well as entire groups. When you have made a selection, click the button "Average of selected". The results will be shown on the right.

Please note that certain dry values will be converted to daf values before they are averaged. The unit column of the results will reflect this. When a conversion is not possible for a particular sample (because the ash content of the sample is not known), the dry value will be used instead.

Discarding outliers

From the averages results page, it is possible to further limit the selection of samples to only those where certain properties have values in a selected range. This function makes it very easy to discard outliers from the results. To use this function, click an input field in the min/max columns of the results, or click the cumulative distribution graph at the end of a row. A bigger graph showing the distribution of the values of the property will open at the top the screen. The horizontal axis shows the values, and the vertical axis the number of samples. You can use the icon at the bottom right of the chart to switch between histogram and cumulative display. Next, it is possible to select a range of values in the chart by left clicking and dragging. After selecting a range, a "Recalculate" button will appear above the table of averages.

The recalculated results will exclude samples where values fall outside the selected ranges. Samples which don't have any value for a property where a range has been selected will still be included. A list of samples that were excluded, and the out-of-range values, is given below the table of averages on the results page.

Definitions used in Phyllis

What is what?

Proximate analysis:

Ash content expressed in weight % on dry base (dry) and on as received material (ar). The amount of ash depends on the temperature of ash formation. If the ash formation temperature is known, the ash content is given at the specific temperature. The ash contents for ar and dry material are related by the water content:
Ash content (wt% dry) = ash content (wt% ar) * 100 / (100 - water content (wt%))

Water content:
Water content in weight %, on wet base (as received). It is important to note that there can be a large difference between the water content of the material as it is available and the water content at the moment of analysis. Also by natural drying during storage the water content can be lowered.

Volatiles and fixed carbon:
The amount of volatile material is determined by standardised methods. The amount of volatiles is expressed in weight % dry material, as received material or dry and ash free material.
The amount of fixed carbon is calculated as the remaining part as determined by the above mentioned standardised method according to the following formulas:

ar fixed C = 100 - ash (ar) - water content - volatiles (ar)
dry fixed C = 100 - ash (dry) - volatiles (dry)
daf fixed C = 100 - volatiles (daf)

Ultimate analysis:

Carbon (C), hydrogen (H), oxygen (O), nitrogen (N), sulphur (S), chlorine (Cl), fluorine (F) and bromine (Br) content in weight % dry material (wt% dry), dry and ash free material (wt% daf) and on as received material (wt% ar).

ar C + H + O + N + S + Cl + F + Br + ash + water content = 100
dry C + H + O + N + S + Cl + F + Br + ash = 100
daf C + H + O + N + S + Cl + F + Br = 100

Often, the oxygen content is not measured but set equal to (100 - measured components). If S and Cl were not considered in the original calculation, or if the 815°C ash content was used instead of the 550°C ash content, the sums will be larger than 100. If the oxygen content was measured, the sums will not equal 100 due to experimental errors in the analyses.

Calorific value (MJ/kg):

The calorific value is expressed as Higher Heating Value (HHV) and Lower Heating Value (LHV). The difference is caused by the heat of evaporation of the water formed from the hydrogen in the material and the moisture:

Nomenclature English Dutch German
HHV Higher heating value
Gross heating value
Calorific value
Heat of combustion
(Oberer Heizwert)
LHV Lower heating value
Net heating value
(Unterer Heizwert)

The determination of the calorific value normally results in a value for the HHV. For comparison, HHV is also calculated from the elemental composition using the Milne formula:

HHVMilne = 0.341·C + 1.322·H - 0.12·O - 0.12·N + 0.0686·S - 0.0153·ash,

where C, H, etc. are the mass and the ash fractions in wt% of dry material and HHV the heating value for dry material in MJ/kg.
By using the hydrogen and ash fractions (wt% dry) and moisture fraction w (wt% ar) the different HHV's and LHV's can be calculated.

HHVar = HHVdry · (1-w/100)
HHVdry = HHVdaf · (1-ash/100)
LHVdry = HHVdry - 2.443 · 8.936 H/100
LHVar = LHVdry · (1-w/100) - 2.443 · w/100
LHVar = HHVar - 2.443 · {8.936 H/100 (1-w/100) + w/100}

Ash composition (wt% ash):

A large number of data on the ash composition after conversion is available. In general these data are expressed as weight % of oxides. The selected oxides are not representative for the actual chemical form of the components.

Lead (Pb), cadmium (Cd), copper (Cu), mercury (Hg), manganese (Mn) en chromium (Cr) are expressed in mg/kg ash.

Biomass analysis (mg/kg dry):

The metal content is expressed in mg/kg dry (original) material.

Biochemical composition (wt%):

The biochemical composition of materials is expressed in weight % of the dry material (cellulose, hemi-cellulose, lignin, fats, protein, pectin, starch, extractives, C5 and C6 sugars, total non-structural carbohydrates). If sugar analysis is applied, cellulose = glucan and hemicellulose = sum C5 + sum C6 - glucan - rhamman.

"Total ash + biochemical" gives the sum of ash, cellulose, hemicellulose, lignin, lipids, protein, extractives EtOH/toluene, extractives 95% EtOH, extractives hot water, starch, pectin, rhamnan, and total non-structural carbo-hydrates (TNC).

Report ECN-C--03-064 gives references for the analysis methods "van Soest" and "sugar analysis". They are:

Van Soest:
H.K. Goering and P.J. Van Soest: Forage fiber analysis. Agriculture Handbook No. 379. US Department of Agriculture, 1970.

Sugar analysis:
Tappi T 249 cm 00 (, and/or
ASTM E 1785-01, and/or
T.A. Milne, A.H. Brennan and B.H. Glenn: Sourcebook of methods of analysis for biomass and biomass conversion processes. Elsevier Applied Science, 1990, ISBN 1-85166-527-7

More information related to Phyllis and biomass can be found at: