Comment & Debate
Algae biofuel is a fuel derived from the process of growing algae and decomposing it to extract oils from it that can be burned for energy. It involves the same basic principles underlying all other biofuels, but uses algae instead of corn, wood, sugar, or soy beans to produce the fuel. Algae biofuel is envisioned principally as a fuel for vehicles and a possible replacement for gasoline. With oil prices rising since 2003 and difficulties with other biofuels, interest in algae biofuel has increased. Venture capital began to flood the emerging algae biofuel industry in 2008. Sapphire Energy, an algae biofuel start-up, has raised over $100 million in venture capital, including from Bill Gates’ investment firm Cascade Investment. Recent difficulties, however, with once-lauded alternative energy sources, including hydrogen fuel-cells and corn ethanol, has caused many to question moving forward too quickly with algae biofuel before fully analyzing the pros and cons. The advantages and disadvantages of algae biofuel are framed by some of the following questions. Is algae biofuel a valuable tool in fighting global warming? Is it carbon neutral, emitting only CO2 that it absorbs first during growth? Can it cut emissions? Does algae biofuel yield substantial energy relative to the energy inputs involved in its production? Is algae biofuel good for local environments? Does it require too much water? Does it require too much land and incentivize deforestation as a result? Is biofuel commercially viable? Is it price competitive with oil, other biofuels, and other sources of energy such as solar panels? Should algae be used to filter C02 emissions from coal plants – a form of “clean coal”. How does it compare overall to other alternative sources of energy, particularly other biofuels and solar power? Are electric cars and electricity-generation superior to algae biofuel and all forms of fuel for vehicles and transportation? Should we generally be moving onto the electric grid and away from liquid fuels for vehicles?
Growing algae absorbs C02 in the process of photosynthesis. It is a carbon sink. This is why, when algae biofuels are burned and emit some C02, the emission balance is C02 neutral; it emits only C02 it previously absorbed, adding no new C02 into the atmosphere. Because it is carbon neutral in this way, it is a renewable energy source that can be produced and burned for energy sustainably.
“Another good thing about algae is they multiply very fast. They can double their weight many times in a single day.”
“Another good thing about algae is they multiply very fast. They can double their weight many times in a single day.”
“Research like that being done at the Colorado State University’s (CSU) Engines and Energy Conservation Laboratory and the University of New Hampshire (UNH), suggests that algae could supply enough fuel to meet all of America’s transportation needs in the form of biodiesel.”
“There are very detailed figures on the amount of energy that will come out of the process, yet it is very hard to find any information on the energy and resources needed to make this energy output possible”
“Almost all biofuels used today cause more greenhouse gas emissions than conventional fuels if the full emissions costs of producing these “green” fuels are taken into account…”.
Douglas Parr, chief scientific advisor for Greenpeace UK. – “our main worry is that it comes as a distraction from the fact that aviation has got to do plenty of things aside from algae research in order to become truly sustainable.”
“Algae can obtain carbon from atmospheric carbon dioxide, but the amounts present are insufficient to promote rapid growth. That requires something like smokestack effluents containing more than 10% CO2, and in fact some of the earliest attempts to grow algae as a fuel source were predicated upon the development of pervasive industrial carbon dioxide capture. That’s not happening, and unless it does, real mass production of algal biofuel is scarcely possible.”
“Naples, Fla.-based Algenol Biofuels says it has found a way to inexpensively bring third-generation biofuels to industrial scale…And, unlike most algal biofuel companies, it’s apparently got a licensing deal for an $850 million project to show for it…The company believes its seawater-based process can generate up to a billion gallons of algal ethanol per year from a facility in Mexico.”
Jennifer Holmgren, director of the renewable fuels unit of UOP LLC, an energy subsidiary of Honeywell International Inc said, “If you can get algae oils down below $2 a gallon, then you’ll be where you need to be. And there’s a lot of people who think you can.
Biofuels that are created from land-plants all have specific soil-quality requirements. If soil in an area does not meet the specific nutrient requirements of a biofuel plant-type, that plant cannot be built and used to produce the biofuel in the land-area. Algae, because it grows in water (of almost any kind and quality), is not limited by soil-quality.
“fertilizer for other food crops can be produced by using the leftover nutrients that aren’t used to make the biofuel…after the necessary oils have been extracted from the algae, we use the byproducts (phosphorus and nitrogen) as fertilizer for the food crops that feed the nation–all while extracting C02 from the air.”
“But algae-culture holds the further promise of the potential of small-scale localized systems for food production as well as fuel production. There’s no quicker way to produce food from sunlight, and the time may soon be coming to many parts of the world where food for humans becomes more a more urgent concern than the production of fuel.”
Sapphire Energy, a algae biofuel start-up says, “Critically important, there is no ‘food vs. fuel’ tradeoff. The process is not dependent on crops or valuable farmland. It is highly water efficient, delivering 10 to 100 times more energy per acre than cropland biofuels.”
“…The momentum behind algae has grown tremendously since [last year]. New companies, new methods, and a changing landscape indicate that biofuel from algae is poised to play a larger role…”
The cost of various algae species is typically between US$5–10 per kg dry weight. This is relative expensive, and not really commercially viable.
“you have to build an array of structures [in algae biofuel bioreactors]: the glass or polycarbonate containers themselves, the metal frames, the greenhouses. The production of all this equipment might consume less energy (and money) per square meter than the production of solar panels, but you need much more of it because algae are less efficient than solar plants. Moreover, in closed bioreactors, CO2 has to be added artificially. This is done by bubbling air through the water by means of gas pumps, a process that needs energy. Furthermore, the containers have to be emptied and cleaned regularly, they have to be sterilized, the water has to be kept at a certain temperature, and minerals have to be added continuously (because also here, just as with cellulosic ethanol, “waste” materials are being removed). All these processes demand extra energy.”
“It could be that these businesses are greatly overestimating their energy gains in order to attract capital. One of the few critics of algal fuel, Krassen Dimitrov, calculated that the figures of GreenFuel Technologies are defying the laws of physics. The company says that he is wrong, but his calculations surely look more convincing than the virtually non-existant information on their website.”
“2. Random natural algae tend to start taking over from artificially seeded algae fairly rapidly unless the pond is covered, and covering ponds costs money.”
“2. Random natural algae tend to start taking over from artificially seeded algae fairly rapidly unless the pond is covered, and covering ponds costs money.”
“low-tech methods (comparable to growing corn, soy or palm trees to make ethanol or biodiesel) are being left behind for more efficient ones, using closed glass or polycarbonate bioreactors and an array of high-tech equipment to keep the algae in optimal conditions. Even though some companies still prefer open ponds (like the PetroSun plant that started production last week), this method has serious drawbacks. The main problem is contamination by other kinds of algae and organisms, which can replace the energy producing algae in no time.”
“I might point out that some of the more vociferous algae pimps are suggesting that algae need merely be introduced into a properly designed, water filled bioreactor and the organisms will multiply until the unit is packed to overflowing with tons upon tons of green biomass, all in the space of days. This is patent nonsense. Algae can grow quickly, but only in the presence of sufficient nutrients. Just like any other organism, algae require carbon, nitrogen, phosphorus, and various other minerals.”
Compared with second generation biofuels, algae are high-yield high-cost (30 times more energy per acre than terrestrial crops) feedstocks to produce biofuels. Since the whole organism uses sunlight to produce lipids, or oil, algae can produce more oil in an area the size of a two-car garage than an entire football field of soybeans.
“For the algae-culture projects which use large growing ponds, the potential biodiesel production per acre is 30 to 100 times greater than obtainable with corn, soy and palm oil. However the most efficient systems, called photo-bioreactors, stack clear tubes of water with algae in the sun, requiring very little acreage for significant production. This is the system we are demonstrating at Ecoversity.”
“Ponds also need a lot of space, because sunlight only penetrates the upper layers of a water body. It’s the surface of the pond that counts, not the depth.”
“Ponds also need a lot of space, because sunlight only penetrates the upper layers of a water body. It’s the surface of the pond that counts, not the depth.”
One advantage of many biofuels over most other fuel types is that they are biodegradable, and so relatively harmless to the environment if spilled.
Glen Kertz, president and CEO of Valcent Products, told CNN while conducting a tour of his algae greenhouse on the outskirts of El Paso – “Algae is the ultimate in renewable energy.”
“Minuses: Unlike cellulosic ethanol, the biomass for making a lot of fuel from algae doesn’t yet exist; it has to be grown from scratch.”
This is expensive, and can also mean that new algae biofuel plants and ponds may alter local ecosystems.
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