Algae Faq
Algae Faqs

General Questions

What are algae?

Among the oldest forms of life on Earth, algae are single-celled organisms that grow in water and have evolved over billions of years to become the most efficient producers of plant oils.

Like other plants and organisms, algae use photosynthesis to turn light, carbon dioxide and a few nutrients into the oils, carbohydrates and proteins that make up their cell structure.

Are all algae the same?
No. While there are thousands of different species, algae can be broadly categorized into two main types.

One type, microalgae, are microscopic organisms that live in water as single cells or in colonies. Microalgae grow fast, and some can double in size in 24 hours.

The other type of algae, macroalgae, are more commonly known as seaweed. They are fast-growing marine and freshwater plants that can grow to considerable size.

What can you do with algae?
Algae can be grown and harvested like any other agricultural crop. Once harvested, the oil can be extracted and refined into biodiesel, gasoline and even jet fuel. In addition to algae oil, the protein and carbohydrates in algae can also be used for food, animal feed, health products and supplements, chemicals, pharmaceuticals and even cosmetics.

What is it about algae that make them a good source for biofuels?

  • Algae can produce between 2,000-5,000 gallons of fuel per acre, far more than any other renewable feedstock.
  • Algae can grow on marginal, or non-crop, land, so they don’t compete with valuable agricultural land.
  • They can grow in brackish, salt- or polluted water, so they don’t require freshwater resources.
  • They consume carbon dioxide (CO2) and emit oxygen as they grow, so they help reduce the total amount of CO2 in the atmosphere.


What are the primary reasons behind all the recent interest in making fuels from algae?
There are three reasons for the strong interest in algae as a resource for renewable, domestically-produced fuels. The development of a robust algae-based fuels industry addresses all three.

  • Our future demand for transportation fuels will outstrip the supply, and put enormous pressure on existing supplies, raising prices for fossil fuels.
  • The buildup of greenhouse gases in the atmosphere emissions requires us to find low-carbon alternatives to petroleum fuels.
  • Our long-term national security is dependent on finding domestic, renewable and sustainable energy sources.

How are algae grown?
Algae can be grown both outdoors in large open ponds using the sun’s energy, non-potable water, natural and/or man-made CO2 and nutrients.

Another method is to grow algae in tanks using sugars as the energy source.

They can also be grown in hybrid systems that use solar energy and a controlled environment of nutrients and CO2.

To harvest the algal biomass for oil, the algae are removed from the water, the oil extracted, and then refined for biofuels or other products.

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