by Dr. Susan Page
University of Leicester
4 November 2011
University of Leicester
research into greenhouse gas emissions from oil palm
plantations provides robust measures now being used to
inform international policies on greenhouse gas
A new study on greenhouse gas emissions from oil palm plantations
has calculated a more than 50% increase in levels of CO2 emissions
than previously thought - and warned that the demand for 'green' biofuels could be costing the earth.
The study from the University of Leicester was conducted for the
International Council on Clean Transportation, an international
think tank that wished to assess the greenhouse gas emissions
associated with biodiesel production.
Conditions at a
mature oil palm plantation site, 18 years after conversion:
(left image) open
canopy (causing increased soil temperatures),
limited ground cover
(causing lowered soil moisture content),
fertilization (white patches around palm trunks),
and (right image) a
loose top soil structure (leaning oil palms, footprints).
Biodiesel mandates can increase palm oil
demand directly (the
European Biodiesel Board recently reported big
increases in biodiesel imported from Indonesia) and also indirectly,
because palm oil is the world's most important source of vegetable
oil and will replace oil from rapeseed or soy in food if they are
instead used to make biodiesel.
The University of Leicester researchers carried out the first
comprehensive literature review of the scale of greenhouse gas
emissions from oil palm plantations on
tropical peatland in
Southeast Asia. In contrast to previous work, this study also
provides an assessment of the scientific methods used to derive
They discovered that many previous studies were based on limited
data without appropriate recognition of uncertainties and that these
studies have been used to formulate current biofuel policies.
The Leicester team established that the scale of greenhouse gas
emissions from oil palm plantations on peat is significantly higher
than previously assumed. They concluded that a value of 86 tonnes of
carbon dioxide (CO2) per hectare per year (annualized
over 50 years) is the most robust currently available estimate; this
compares with previous estimates of around 50 tonnes of carbon
dioxide (CO2) per hectare per year.
CO2 emissions increase
further if you are interested specifically in the short term
greenhouse gas implications of palm oil production - for instance
under the EU Renewable Energy Directive which assesses emissions
over 20 years, the corresponding emissions rate would be 106 tonnes
of carbon dioxide (CO2) per hectare per year.
The findings have been published as an International White Paper
from the ICCT.
plantations on peat:
note the leaning
trunks owing to low load-bearing capacity of peat soils.
Ross Morrison, of the University
of Leicester Department of Geography, said:
"Although the climate change impacts
of palm oil production on tropical peatland are becoming more
widely recognized, this research shows that estimates of
emissions have been drawn from a very limited number of
scientific studies, most of which have underestimated the actual
scale of emissions from oil palm.
These results show that biofuels
causing any significant expansion of palm on tropical peat will
actually increase emissions relative to petroleum fuels. When
produced in this way, biofuels do not represent a sustainable
Dr Sue Page, Reader in Physical
Geography at the University of Leicester, added:
"Tropical peatlands in Southeast
Asia are a globally important store of soil carbon - exceeding
the amount stored in tropical forest vegetation. They are under
enormous pressure from plantation development.
Projections indicate an increase in
oil palm plantations on peat to a total area of 2.5Mha by the
year 2020 in western Indonesia alone - an area equivalent in
size to the land area of the United Kingdom."
Growth in palm oil production has been a
key component of meeting growing global demand for biodiesel over
This growth has been accompanied by
mounting concern over the impact of the oil palm business on
tropical forests and carbon dense peat swamp forests in particular.
Tropical peatland is one of Earth's largest and most efficient
Development of tropical peatland for agriculture and
plantations removes the carbon sink capacity of the peatland system
with large carbon losses arising particularly from enhanced peat
degradation and the loss of any future carbon sequestration by the
native peat swamp forest vegetation.
Although there have been a number of assessments on greenhouse gas
emissions from palm oil production systems, estimates of greenhouse
gas emissions from land use have all been based on the results of a
limited number of scientific studies.
A general consensus has emerged that
emissions from peat degradation have not yet been adequately
The results of the Leicester study are important because an increase
in the greenhouse gas emissions associated with biodiesel from palm
oil, even if expansion on peat only occurs indirectly, will negate
any savings relative to the use of diesel derived from fossil fuel.
If these improved estimates are applied to recent International Food
Policy Research Institute (IFPRI) modeling of the European biofuel market,
they imply that on average biofuels in Europe will be as carbon
intensive as petrol, with all biodiesel from food crops worse than
fossil diesel and the biggest impact being a 60% increase in the
land use emissions resulting from palm oil biodiesel.
Bio-ethanol or biodiesel from waste
cooking oil, on the other hand, could still offer carbon savings.
pole inserted in peatland in Johor, peninsular Malaysia.
The pole was inserted
beside an oil palm plantation in 1978 and at the time of this
photograph (2007), 2.3 m...
This outcome has important implications
for European Union policies on climate and renewable energy sources.
Dr Sue Page said:
"It is important that the full
greenhouse gas emissions 'cost' of biofuel production is made
clear to the consumer, who may otherwise be mislead into
thinking that all biofuels have a positive environmental impact.
In addition to the high greenhouse
gas emissions associated with oil palm plantations on tropical
peatlands, these agro-systems have also been implicated in loss
of primary rainforest and associated biodiversity, including
rare and endangered species such as the orangutan and Sumatran
"We are very excited by the outcomes of our research - our study
has already been accepted and used by several scientists, NGOs,
economists and policy advisors in Europe and the USA to better
represent the scale of greenhouse gas emissions from palm oil
biodiesel production and consumption.
"The findings of this research will be used by organizations
such as the US Environmental Protection Agency, European
Commission and California Air Resources Board to more fully
account for greenhouse gas emissions and their uncertainties
from biofuel produced from palm oil.
This is essential in identifying the
least environmentally damaging biofuel production pathways, and
the formulation of national and international biofuel and
Dr Chris Malins of the ICCT said,
"Peat degradation under oil palm is
a major source of emissions from biodiesel production.
Recognizing that emissions are larger than previously thought
will help regulators such as the US Environmental Protection
Agency (EPA), European Commission (EC) and California Air
Resources Board (CARB) identify which biofuel pathways are
likely to lead to sustainable greenhouse gas emissions
The research was funded by the International Council on Clean
Transportation (ICCT), an international think-tank made up of
representatives from the world's leading vehicle manufacturing
The research was commissioned by Dr
Chris Mallins of the ICCT and led by Dr Susan Page and
Morrison, both of the Department of Geography, University of
Other contributors to the work were,
Professor Jack Rieley of the
University of Nottingham and chair of the scientific
advisory board of the International Peat Society (IPS)
Dr Aljosja Hooijer of Deltares
in the Netherlands
Dr Jyrki Jauhiainen of the
University of Helsinki
The research was conducted over a period
of three months during spring of this year and has recently been
published as an International White Paper by the ICCT.