Presented by
Omkar Joshi, Dr. Donald L. Grebner, Dr.
Ian A. Munn, Dr. Stephen C. Grado,
Dr. Robert K. Grala, Dr. James E.
Henderson
Department of Forestry
Mississippi State University
 Introduction
 Methods
 Results
 Discussion
 Conclusion
and Implications
 Environmental
benefits
 Economic benefits
 Energy security benefits




Bioenergy can be produced from different sources
including mill residues
Mill residues can be obtained from primary and
secondary forest product industries
Primary Industries: Industries that convert woody
biomass into wood products (such as: lumber, plywood,
logs, particleboard etc.)
Secondary Industries: Industries that utilize primary
wood products (such as: furniture, flooring,
cabinet/millwork, pellets, panels etc.)
 Mill
residues contribute to 50% of the existing
biomass energy consumption in US

Mill residues are better suited, as feedstock, to
others due to relative cleanliness and higher
density
 Significant
amount of the mill residues are
currently utilized to generate energy
 Despite
this, large volumes are still sold for
other purposes
 Likewise, some
volumes are either given away
or disposed of in United States
 Literature
pertaining to the factors affecting
availability of unused woody residue in mill is
limited
 Current
study is conducted to fill the gap in
knowledge in the region
Therefore relevant questions are:
 How
much internally unused mill woody
residue is available in Mississippi?
 Are
mill owners interested to find the
better ways to utilize woody residues?
 What
could be the factors that influence
availability of residues in a mill?
 Identify
the estimates on total regenerated
wood residues in Mississippi
 Analyze
and identify the factors affecting
availability of mill residues in the state of
Mississippi
A
mail survey was designed to obtain data on
availability of unused woody residues in
Mississippi woody processing facilities
A
version of the Dillman Tailored Design Method
(2000) was employed
 Survey
instrument consisted of three sections:
• Type of wood residues generated
• Methods of woody residue utilization
• Socio-demographic information
 Population
 Number
Size: 458
of respondents: 99
 Adjusted
response rate of survey was
21.6%
 Non-response
bias was not an issue
 Among
the Mills, 54% were Primary, 28%
were Secondary and 18% had both
facilities
 Monthly
generated volumes of wood
residue from all respondent facilities was
208,489.73 tons, of which 92% was
contributed by primary mills



Out of total regenerated woody residues, 69%
was internally used, 30% was sold and 1% was
given away
40% of the respondents realized the need of
potential market for wood residues near their
facility
79% of the respondents were interested in
working with other manufacturers to determine
the better ways to utilize wood residues
Econometric Model
Dependent variable : Amount of unused woody residue available
Econometric model: Least square regression model, Tobit model
Independent variables
Mill characteristics : Mill type (PRI), no. of employee
(EMPLOYEE), technical capacity (BETTER), year of operation
(YEAR), season of mill operation (SEASON), organization
structure (ORG)
Market opportunities and others: Availability of nearby market
(MARKET), interest to work together for finding better method
for utilization (Work)
Demographic : Education (EDU1, EDU2, EDU3)
Generalized Least Square Model:



Autocorrelation and multicollinearity were not an
issue
The diagnostic tests revealed that data violated the
assumption of normality and heteroscedasticity
Assumptions were met after logarithmic
transformation [ Y’= Log(1+Y)] of dependent
variable



Since some millowners who internally utilized
woody residues had zero volumes available, Tobit
Model would be argued to be better model to
analyze data
Since sample size was small, maximum likelihood
based methods might provide biased estimates
Therefore, both models were analyzed and
compared
Variables
Generalized least
square
Coefficient
Tobit Model
T-value Coefficient
1.06*
1.93
0.999
PRI
BETTER
0.498
0.929
0.522
EMPLOYEE
0.797*
1.871
0.764
YEAR
-0.013
-0.862
-0.012
SEASON
2.50*
1.721
2.466*
MARKET
1.161*
1.906
1.169*
WORK
1.439 **
2.118
1.490*
EDU2
-0.472
-0.678
-0.524
EDU3
-1.610*
-1.986
-1.680*
Intercept
-0.65
-0.58
F-statistics value 2.54
Log-likelihood
Sample size (N)
61
**Significant at 95% *Significant at 90%
b/st.err
1.546
0.785
1.479
-0.746
1.719
1.859
1.850
-0.644
-1.798
-133.7


Since higher volumes of woody residues are
generated in primary wood processing mills, higher
availability of unused woody material in such firms
seems justifiable
As larger and year round operating mills usually
generate more woody residues, results are
meaningful



Results indicate that the availability of unused woody
residue might have prompted mill owners to express
their interest to work with other forest product industries
Managerial skills given higher education might have
helped millowners to efficiently utilize the woody
residues obtained
While the available amount of woody residue is higher in
the mills having a nearby market, there might be
competition among buyers to obtain woody residues in
such facilities


Bioenergy can be generated in a cheaper price if
the industry could be located nearby a primary,
large and year round operational mill
Millowners having less formal education might
benefit from awareness activities related to woodbased bioenergy


As most of the available woody residues in the state
are sold, entrepreneurs might need to pay a
competitive feedstock price to operate wood-based
bioenergy facility in Mississippi
Appropriate location of wood-based bioenergy
industry should be an important consideration to
ensure low cost wood-based bioenergy production
Marcus K. Measells
Dr. Anwar Hussain
Thank You