9.5 Biodiesel Production with Microalgae
Research on the use of microalgae to make fuel intensified as a result of the two oil
shocks of the 1970s. In the U.S., the National Renewable Energy Laboratory
(NREL) conducted an 18-year Aquatic Species Program (ASP) between 1978 and
1996 in an effort to use microalgae for biodiesel production. This research and
development was not sustained as oil prices stabilized and difficulties were
encountered in the maintenance and management of outstanding species when
mass-culturing microalgae in ponds, along with technical hurdles related to
molecular microalgae improvements. With food, environment, and energy issues
emerging at the global scale over the past years, however, the rise in crude oil prices
has sparked renewed interest in biofuels such as biodiesel and ethanol (Miao and
Wu 2006; Khan et al. 2009; Lardon et al. 2009; Mata et al. 2010; Campbell et al.
2011; Yang et al. 2011).
Biofuel production to date has chiefly involved the production of ethanol and
biodiesel from sources such as corn, sugarcane, beans, rapeseed, and palm.
A number of difficulties have surfaced, including the finite nature of these resources
and the ethical issues attendant on converting grain into energy. Microalgae are not
in competition with grains, however, and offer number advantages, including the
ability to use idle farmland for biodiesel production, the relative ease of molecular
biological improvements compared to plants, and biodiesel yields up to ten times
greater or more than soybeans per unit area of farmland.
Like plants, microalgae synthesize organic matter through photosynthesis, using
carbon dioxide, water, and solar energy. At the same time, they possess a number of
advantages as renewable energy sources: they have faster growth rates than plants,
they are more amenable to functional improvements through gene manipulation that
allow the production of a greater variety of useful substances, and they are not
traditional food crops. Indeed, biodiesel production (with 30% oil content) using
microalgae amounts to around 58,700 L per hectare of farmland, or roughly 130
times greater than the 446 L/ha for soybeans. It is for this reason that the science
journal Nature described microalgae biodiesel as “green gold,” an analogy to the
name “black gold” for crude oil. Through mass culturing of microalgae, it is
possible to use carbon dioxide to produce large amounts of biomass, which can be
converted into biofuel.
Mass culturing of microalgae is thus a form of green technology that is capable
of preventing global warming through its absorption of atmospheric CO 2 , while at
the same time producing biodiesel from the resulting algae biomass. Moreover,
biological conversion and processing of CO 2 is an environmentally friendly
approach that takes advantage of photosynthesis, one of the basic means by which
matter circulates in the natural world. Other advantages include the fact that it takes
place at normal temperature and pressure, which allows for a simple process, and
that the biomass produced through it can be used for useful substances.
9.5 Biodiesel Production with Microalgae
331
Research on the use of microalgae to make fuel intensified as a result of the two oil
shocks of the 1970s. In the U.S., the National Renewable Energy Laboratory
(NREL) conducted an 18-year Aquatic Species Program (ASP) between 1978 and
1996 in an effort to use microalgae for biodiesel production. This research and
development was not sustained as oil prices stabilized and difficulties were
encountered in the maintenance and management of outstanding species when
mass-culturing microalgae in ponds, along with technical hurdles related to
molecular microalgae improvements. With food, environment, and energy issues
emerging at the global scale over the past years, however, the rise in crude oil prices
has sparked renewed interest in biofuels such as biodiesel and ethanol (Miao and
Wu 2006; Khan et al. 2009; Lardon et al. 2009; Mata et al. 2010; Campbell et al.
2011; Yang et al. 2011).
Biofuel production to date has chiefly involved the production of ethanol and
biodiesel from sources such as corn, sugarcane, beans, rapeseed, and palm.
A number of difficulties have surfaced, including the finite nature of these resources
and the ethical issues attendant on converting grain into energy. Microalgae are not
in competition with grains, however, and offer number advantages, including the
ability to use idle farmland for biodiesel production, the relative ease of molecular
biological improvements compared to plants, and biodiesel yields up to ten times
greater or more than soybeans per unit area of farmland.
Like plants, microalgae synthesize organic matter through photosynthesis, using
carbon dioxide, water, and solar energy. At the same time, they possess a number of
advantages as renewable energy sources: they have faster growth rates than plants,
they are more amenable to functional improvements through gene manipulation that
allow the production of a greater variety of useful substances, and they are not
traditional food crops. Indeed, biodiesel production (with 30% oil content) using
microalgae amounts to around 58,700 L per hectare of farmland, or roughly 130
times greater than the 446 L/ha for soybeans. It is for this reason that the science
journal Nature described microalgae biodiesel as “green gold,” an analogy to the
name “black gold” for crude oil. Through mass culturing of microalgae, it is
possible to use carbon dioxide to produce large amounts of biomass, which can be
converted into biofuel.
Mass culturing of microalgae is thus a form of green technology that is capable
of preventing global warming through its absorption of atmospheric CO 2 , while at
the same time producing biodiesel from the resulting algae biomass. Moreover,
biological conversion and processing of CO 2 is an environmentally friendly
approach that takes advantage of photosynthesis, one of the basic means by which
matter circulates in the natural world. Other advantages include the fact that it takes
place at normal temperature and pressure, which allows for a simple process, and
that the biomass produced through it can be used for useful substances.
9.5 Biodiesel Production with Microalgae
331