Algae for Biofuels
Much of the information
here about algae has been adapted, abbreviated, quoted, and summarized from two
websites listed at the end of this brief introduction about the use of algae
for biofuels. It should give you a good
idea of why Michael, Dick, and JD are so excited in Zero Emissions about a breakthrough in algae-based green gas.
Now, let's start at the beginning
by defining algae. They are simple
plants that can range from the microscopic (microalgae) to large seaweeds like
giant kelp (macroalgae). The biofuel in Zero
Emissions we're interested in comes from microalgae. And most microalgae grow through photosynthesis
– by converting sunlight, CO2 and a few nutrients, including nitrogen and
phosphorous, into material known as biomass.
Algae are found pretty much everywhere on the planet and
play an important role in many ecosystems, as well as producing about 70
percent of all the air we breathe. They
can be cultivated on land in large ponds, or in enclosed photo bioreactors
using enriched CO2. They can reproduce
fast, faster than any other plants, and there are tens of thousands of species
of algae, with more discovered every day.
There isn't one single way to grow algae at a commercial scale, and this
versatility is one of algae’s strengths, with the approach taken designed to
maximize algae growth for production of fuel, chemicals or other industrial products.
Using algae as a source of food, feed and energy isn't
new. Production of methane gas from algae was put forward in the early 1950s,
and received a big boost during the energy crisis of the 1970s, when projects
were initiated to produce gaseous fuels (hydrogen and methane). From 1980 to
1996 the US Department of Energy supported a relatively small effort (about $25
million over almost 20 years) with the specific goal of producing oil from
microalgae.
More recently, rising global demand for transportation
fuels, concern over increasing impacts of atmospheric CO2, the ongoing importation of
fuel, and the energy security risks that come with that, among other things, has
kept the interest of biofuels in general and algae-based biofuels in particular
in the news. And advances in
biotechnology, such as the ability to genetically engineer algae to produce
more oils and convert solar energy more efficiently, have unleashed new
possibilities for algae research and commercial viability. The US is the leader in advancing algae-based
fuels, although efforts are underway globally as well.
Algae are promising as long-term, sustainable sources of
biomass and oils for fuel, food, feed, and other co-products primarily because
of the large number and wide variety of benefits associated with how and where
they grow. Algae have evolved to produce
and store energy in the form of oil more efficiently than other known natural
or engineered processes.
What makes algae a promising new source of fuel (and other
products) is put forward by the all About Algae website listed at the end of
this piece, and this article lists the benefits of algae "as:
1) Algae Grow Fast. ?Algae can double their
numbers every few hours, can be harvested daily, and have the potential to
produce a volume of biomass and biofuel many times greater than that of our
most productive crops.
2) Algae Can Have High Biofuel Yields. ?Algae
store energy in the form of oils and carbohydrates, which, combined with their
high productivity, means they can produce from 2,000 to as many as 5,000 gallons of biofuels per acre per year.
3) Algae Consume CO2. ?Like any other plant, algae,
when grown using sunlight, consume (or absorb) carbon dioxide (CO2) as they
grow, releasing oxygen (O2) for the rest of us to breathe. For high
productivity, algae require more CO2, which can be supplied by emissions
sources such as power plants, ethanol facilities, and other sources.
4) Algae Do Not Compete With Agriculture. ?Algae
cultivation uses both land that in many cases is unsuitable for traditional
agriculture, as well as water sources that are not useable for other crops,
such as sea-, brackish- and wastewater. As such, algae-based fuels complement
biofuels made from traditional agricultural processes.
5) Microalgal Biomass Can Be Used for Fuel, Feed and Food.
Microalgae can be cultivated to have a high protein and oil
content, for example, which can be used to produce either biofuels or animal
feeds, or both. In addition, microalgal biomass, which is rich in
micronutrients, is already used for dietary supplements to advance human
health.
6) Macroalgae Can Be Grown in the Sea. ?Macroalgae
(seaweeds) are grown in the sea, or even on land with seawater, and their
sugars can be converted into biofuels and chemicals.
7) Algae Can Purify Wastewaters. ?Algae
thrive in nutrient-rich waters like municipal wastewaters (sewage), animal wastes
and some industrial effluents, at the same time purifying these wastes while
producing a biomass suitable for biofuels production.
8) Algal Biomass Can Be Used as an Energy Source. ?After oil
extraction, the remaining algal biomass can be dried and “pelletized” and used
as fuel that is burned in industrial boilers and other power generation
sources.
9) Algae Can Be Used to Produce Many Useful Products. ?Algae can
be cultivated to produce a variety of products for large to small markets:
plastics, chemical feedstocks, lubricants, fertilizers, and even cosmetics.
10) The Algae Industry is a Job Creation Engine. ?Algae can
grow in a wide variety of climates in a multitude of production methods, from
ponds to photo bioreactors to fermenters, and thus will create a wide variety
of jobs throughout the United States, from research to engineering, from
construction to farming, from marketing to financial services. The Algal Biomass Association projects the
potential for creation of 220,000 jobs in this sector by 2020."
In summary, while we aren't totally there with a perfect algae-based
biofuel such as what Michael and Dick are working on in Zero Emissions, this science is very real and really exciting. Take a look at these websites for more
information.
How Algae Biodiesel Works
All About Algae