Renewable

Energy Sources

For years researchers have been interested in a truly green fuel source: microalgae.  Often confused with seaweed, which falls into the category of macro algae, microalgae contains high amounts of the necessary fatty oils called triacylglycerols that can be used to make biodiesel, or what some call “oilgae.” Biodiesel can replace petroleum diesel one-to-one with little or no modification of machinery.

Unlike corn, which requires a lot of land, water and fertilizer, algae requires relatively little space, uses clean and recyclable seawater, and its use for fuel does not detract from the food supply, as the use of corn and other edible plants does.  As one of the most primitive plant species, algae have a simple structure that also allows for easier conversion into biodiesel.  Algae reproduce quickly and when transformed into biodiesel, leave a small carbon footprint. Algae is nourished by carbon dioxide, the primary global warming gas, and can actually recycle carbon dioxide emissions from electric generating power plants and other industries.  Further, algae produces a higher energy yield than most other biofuel sources (see chart below).

Chart courtesy of HR BioPetroleum

Companies across the nation are already working to transform algae into a viable fuel source.   For example, PetroSun, an Arizona-based diversified energy company, has been researching the development of algae for jet fuels at an algae farm in Texas with plans to establish more algae farms and algae oil extraction plants in Louisiana, Arizona, Mexico and Central America.  However, to date HR BioPetroleum is one of only two firms to successfully move algae production from the lab to the farm. 

Since 2004, HR BioPetroleum has operated a pilot facility in Kailua-Kona, Hawaii Island, to test its proprietary algae cultivation technology that uses marine algae to convert industrial carbon dioxide emissions into biomass feedstocks for use as biofuels. While many algae farms only use one method for algae cultivation, HR BioPetroleum’s technology uses two methods to cultivate algae for oil use. In the first stage, cultivation of the algae is done in a closed system which protects it from outside contaminants and also allows for maximum exposure to the sun.  In the second phase, the algae are moved into open ponds to continue growth. 

Chart courtesy of HR BioPetroleum

After the algae are cultivated, it is then harvested and the algal oil is squeezed out, leaving a residue that can be used for animal feed and other high value products.  To make biodiesel the algal oil is tread treated with sodium ethanolate and ethanol in a process called transesterification.   By the end of the process, the algae’s lipids are transformed into biodiesel and the non-fuel residual can be used for animal feed and other products.

The results from HR BioPetroleum’s pilot facility inspired new methods for algae cultivation that attracted European fuel company Royal Dutch Shell to partner with the company in 2007.  Under their alliance, called Cellana, the joint venture demonstration project is further testing large-scale production of algae for potential commercial deployment using the open pond system. 

Performance data results from Cellana’s Kona demonstration project are critical to the development of a commercial algae growing facility announced in 2008 between partners HR BioPetroleum, Alexander & Baldwin, Hawaiian Electric Company and Maui Electric Company.  By building the facility adjacent to Maui Electric’s Ma‘alaea Power Plant, HR BioPetroleum ideally will be able to capture carbon dioxide emissions from the plant for use in nourishing the algae to be turned into useable biofuels. This project will benefit from the research being done at both the pilot and demonstration facilities on Hawaii Island.

The environmental impacts of algae farming continue to be an important consideration.  In the unlikely case of a water and algae break from the farm, the water used by the facility will actually hold less contaminant than natural ocean water and the microalgae used will also be a common, non-genetically modified species that naturally occurs in Hawaii’s waters.  This means the algae will be at home in Hawaiian waters and have to compete with the same food supply as the indigenous algae.  The competition of a larger population for a limited food supply will organically restore the algae to its natural levels in the area.

As a promising source of sustainable and secure fuel, algae could play a vital role in providing clean and renewable energy for the state of Hawaii in the future.

For more on research and development of algae for fuel, visit these sites:

U.S. Department of Energy: Biodiesel from Algae

HR BioPetroleum

How Algae Biodiesel Works

Algae to Biodiesel Video, provided courtesy of Valcent Products (www.valcent.net) and Global Green Solutions, Inc. (www.globalgreensolutionsinc.com)