Algae fuel (green crude)
Algae fuel, often referred to as green crude, is a type of biofuel derived from algae, a diverse group of green aquatic plants rich in oil. As a renewable energy source, algae fuel offers a potential alternative to traditional fossil fuels, which are nonrenewable and contribute to environmental degradation. The cultivation of algae is advantageous because these organisms can grow rapidly using only water, sunlight, and carbon dioxide, thus requiring less land and not competing with food crops. This makes algae a particularly attractive option for biofuel production, especially as concerns about food security and environmental impact arise with conventional biofuel sources.
Algae can be cultivated in both open ponds and controlled indoor environments, although there are challenges such as maintaining water temperature and preventing contamination. Despite initial excitement about the prospects of algae fuel in the late 20th and early 21st centuries, various issues, including high production costs and competition from other renewable energy sources, have hampered widespread adoption. Nonetheless, research and development efforts continue, with hopes that by 2050, algae-derived fuels can be produced at a cost comparable to fossil fuels. The U.S. Department of Energy remains invested in advancing algae bioenergy and bioproducts, as the search for sustainable energy solutions continues.
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Algae fuel (green crude)
Algae fuel, also known as green crude, is a type of biofuel. Biofuels are renewable energy sources made from materials that can easily be replaced, such as plants. Algae fuel is made from algae, green aquatic plants that contain high levels of oil. Biofuel is an alternative to gasoline, which is made from fossil fuels, a nonrenewable energy source. Biofuels were created to replace fossil fuels; as of the twenty-first century, however, they are not utilized nearly as much as fossil fuels are in many parts of the world.
Background
Most energy sources (petroleum, natural gas, coal, etc.) used worldwide are nonrenewable fossil fuels, which are made from decomposed plants and animals from millions of years ago that were buried in the ground. Many countries depend on these forms of energy. Because fossil fuels cannot be replaced and stores eventually will be depleted one day, countries need to further develop biofuels—among other energy sources—to take the place of fossil fuels.
Production of biofuels has existed for decades. Ethanol and biodiesel were the most common types developed in the early nineteenth century. Ethanol is an alcohol made by fermenting a crop, such as corn or sugarcane, and then converting the fermented crop to ethanol. Ethanol is used as a substitute for gasoline or is blended with gasoline. Biodiesel is a mixture of alcohol, such as methanol, and oil, such as vegetable oil, soybean oil, animal fat, or recycled cooking grease. Biodiesel also may be used as a gasoline substitute.
These types of biofuels are produced using both food crops and fossil fuels, so they are not considered completely renewable. The process of growing, harvesting, and fermenting crops into biofuels consumes energy in the form of nonrenewable energy sources. Much debate exists as to whether biofuels provide more energy than is used to develop them. Biofuels use food crops that many people argue could feed people in impoverished parts of the world. This also has led to an increase in food prices. In addition, these crops require large tracts of land, which are usually inhabited by other species that are forced from their natural habitats when the land is cleared for crop use.
For these reasons, scientists began to research other materials to make biofuels. They wanted to eliminate using food crops and reduce the amount of energy it takes to produce biofuels. In the 1950s, scientists began researching algae as a possible energy source. It received notice two decades later during the energy crisis, and several projects were developed to produce methane gas and hydrogen gas from algae.
More than one hundred thousand species exist in the algae family. Common forms include protozoa found in ponds and seaweed found in oceans. Kelp, moss, and fungus that grow on rocks are other kinds of algae. Algae are easy to grow because they need only water, sunlight, and carbon dioxide; they make their own food through the process of photosynthesis, consume carbon dioxide in the air, and release oxygen.
Algae can grow in very large amounts without disturbing habitats or food sources. For example, algae grow on the tops of ponds without disturbing wildlife below the surface of the water. Algae can be grown indoors and grows at a faster rate than food crops such as corn or soybeans. Certain types of algae, such as pond scum, contain higher levels of oil and are better for making biofuels. The oil is extracted from the algae using a press, and then it is chemically processed into biofuel. Algae's by-products are then used for other purposes, including as fertilizer or feed for livestock.
Algae seem like ideal materials from which to make biofuels, but algae production has its downfalls. Algae can be grown in open ponds, but the water temperature must be maintained. Algae also require high levels of carbon dioxide, which can harm wildlife and contaminate water sources. However, algae can be grown in humanmade water sources and indoors in labs, which could solve most of these issues.
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Algae appeared to be the answer to the world's fossil fuel problems in the late twentieth and early twenty-first century. The plants can be produced with less land and energy, and they do not take away from food production. Algae also was promising in helping to curb carbon emissions because the plants thrive on carbon dioxide. Many companies, including Shell and ExxonMobil, rushed to explore the development of algae for biofuel production. Around the same time, ethanol production received some renewed interest in the United States. This was short-lived, however, as ethanol production, which requires the use of food crops, was blamed for creating a global food price crisis. The United States again looked to biofuel production using nonfood crops, such as algae.
As companies turned to algae fuel production, oil production increased and prices continued to drop. This hindered the algae fuel industry, and many companies began to fail. Other issues plagued the industry. Monitoring ponds for algae production was difficult, and contamination spoiled much growth. Building humanmade ponds specifically for growing algae was costly. In addition, the US Department of Energy (DOE) had begun to cut biofuels research and projects. By the early 2010s, many companies abandoned their plans for algae fuel and looked to use algae in other ways, such as producing the plants as dietary supplements, food products, and bioplastic.
The algae biofuel industry received some good news at the end of 2016, when the US DOE announced funding for companies looking to advance algae bioenergy and bioproducts. However, because other renewable alternatives, such as solar, wind, and geothermal, outpaced algae fuel in terms of innovation, cost, and implementation, algae biofuel remained in the research and development phase. Despite this, the DOE and its partners aimed to demonstrate significant algae growth and scale up production in outdoor ponds by 2025. The DOE has stated that, by 2050, it hopes to produce an algae strain that, when used to make fuel, is as cost-efficient as using fossil fuels for energy.
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