Macroalgas

Working Document of the NPC Future Transportation Fuels Study Made Available August 1, 2012

Topic Paper #12 Macroalgae (Seaweeds)

On August 1, 2012, The National Petroleum Council (NPC) in approving its report, Advancing Technology for America’s Transportation Future, also approved the making available of certain materials used in the study process, including detailed, specific subjectmatter papers prepared or used by the study’s Task Groups and/or Subgroups. These Topic Papers were working documents that were part of the analyses that led to development of the summary results presented in the report’s Executive Summary and Chapters. These Topic Papers represent the views and conclusions of the authors. The National Petroleum Council has not endorsed or approved the statementsand conclusions contained in these documents, but approved the publication of these materials as part of the study process. The NPC believes that these papers will be of interest to the readers of the report and will help them better understand the results. These materials are being made available in the interest of transparency.


 
 
 New
 Fuels:
 
 Macroalgae
  Future Transportation
 Fuels
 Study,
 National
 Petroleum
 Council
 
  Julie
 Rothe1,
 Dirk
 Hays1
 and
 John
 Benemann2
 
1

Department
 of
 Soil
 and
 Crop
 Sciences,
 Texas
 A&M
 University,
 College
 Station,
 Texas
 
 and
 2Benemann
 Associates,
 Walnut
 Creek,
 California
 
 


  What are
 Macroalgae?
  Macroalgae,
 or
 seaweeds,
 are
 multicellular,
 macroscopic,
 marine
 algae,
 defined
 as
 non-­‐vascular
  plants.
 
 Compared
 to
 microalgae,
 whose
 production
 is
 estimated
 at
 no
 more
 than
 20,000
 tons
  (dry
 weight
 matter)
 per
 annum,
 global
 production of
 seaweeds
 exceeds
 a
 million
 tons,
 and
 their
  biomass
 sells
 for
 almost
 ten-­‐fold
 less
 than
 that
 of
 microalgae.
 
 
 Less
 than
 10%
 of
 global
 seaweed
  production
 is
 from
 the
 harvest
 of
 natural
 stands.
 The
 remainder
 is
 cultivated
 in
 near-­‐shore  plantations,
 over
 80%
 being
 produced
 in
 China,
 with
 the
 Philippines
 and
 Japan
 being
 additional
  major
 production
 centers
 (Bruton
 et
 al.,
 2009).
 
 Seaweeds
 are
 cultivated
 near-­‐shore
 at
 shallow
  depth,
 where
 the
 seaweeds
 can
 attach
 to
 bottom
 substrates (natural
 or
 artificial;
 seaweeds
  cannot
 grow
 in
 sandy
 bottoms),
 or,
 at
 greater
 depth,
 where
 underwater
 ropes
 strung
 out
 in
  long
 lines
 anchor
 seaweed
 to
 the
 bottom,
 typically
 in
 areas
 protected
 from
 direct
 storm
 surges.
 
  Specific
 cultivation techniques
 depend
 on
 locality
 and
 seaweed
 species.
 
 
 
  Compared
 to
 microalgae,
 macroalgae
 typically
 have
 a
 higher
 carbohydrate,
 and
 lower
 protein
  and
 lipid
 contents.
 
 Carbohydrate
 percentages
 in
 macroalgae
 can
 range
 up
 to
 80%
 organic
  matter
 (ash-­‐free dry
 weight),
 though
 60%
 organic
 matter
 with
 contents
 of
 about
 20%
 protein
  and
 15%
 lipids
 are
 more
 typical.
 
 Literature
 reports
 on
 composition
 vary
 considerably
 based
 on
 

1

methods
 of
 analysis,
 growth
 conditions,
 and
 species
 studied,
 not
 to...