As the US tries to move towards a clean energy economy and zero carbon emissions by 2050it seems that biofuels have their moment. These renewable fluids can be a a direct substitute for energy for oil-absorbing vehicles, or industrial processes without the need to change the entire grid infrastructure.
In particular, it seems that the government is paying attention to green slime that can meet some of the energy needs of Americans: algae.
Earlier in February, the Department of Energy’s Office of Bioenergy Technology (BETO) announced a new round of funding of $ 19 million for projects that can increase the ability of working algae systems to capture carbon dioxide. Objectives two: to reduce greenhouse gas emissions and cultivate algae to produce biofuels and other bioproducts.
This ad is based on funding of previous yearsincluding round of grants for a total of $ 8 million issued in the summer of 2021. Although these figures are pale compared to the total budget of the Ministry of Energy for 2022 is $ 40.3 billionalgae bioenergy seems to be growing interest – there is even new student competition introduces innovations with water-based organisms.
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The ultimate goal, says Seanne Manning, an associate professor of molecular bioscience at the University of Texas at Austin, is to displace fossil fuel dependence by using bioenergy instead. Manning is also the director of research and development at the university cultural collection of algae, which sells its shares to aquaculture and biotechnology companies, as well as individual researchers and small business owners. But, as she emphasizes, there are several obstacles at different stages of algae production, from cultivation to harvesting to subsequent operations to transform organisms into market-ready products.
Technically most of the energy comes mostly from algae. Crude oil, which gives the fossil fuel industry its strength, is the result ancient algae deposits. After millions of years of heat and pressure, marine life, such as plants and eukaryotes, have evolved into the hydrocarbons that make up oil today. But engineered algae for on-demand oil production may provide a less carbon solution for energy needs. Grant projects represent a number of approaches, including the use of algae from direct air capture and animal feed.
On st Arizona Center for Technological Innovation in Algae the University of Arizona uses large open water bodies to grow algae. Algae technology is used to create renewable products such as biofuels, plastic alternatives and nutraceuticals, which are nutritious foods that can also be used as medicines similar to green tea and ginseng.
One of the key problems that Manning cites is that although these ponds may look as dense as pea soup, algae only make up one percent of the total volume of the pond. The rest of the floating biomass is water. This is one of the main problems in large-scale algae cultivation: to obtain a high density, a lot of water needs to be removed from the equation (most of which ends up being reused in the system). According to Manning, the process of harvesting and dehydration could take up 70 percent of capital expenditures.
In search of a solution, the engineers of the Pacific Northwest National Laboratory drew inspiration from the Earth’s processes and came up with fuel-forming method called hydrothermal liquefaction. Instead of extracting oil separately, they prepare algae, proteins and all this at incredibly high temperatures and pressures to mimic how oil is formed under water. Although still conducted only on a small scale, this may be one of the proposed solutions to miss out on expensive dehydration costs.
Another recently funded project Illinois Center for Sustainable Technology aims to reduce the cost of cultivation and resources through the use of carbon dioxide from the flue gases emitted at a nearby power plant, along with nutrients from sewage treatment plants. The system, which will be located at the city’s power plant for water, light and electricity in Springfield, Illinois, aims to grow algae as an alternative to animal feed.
According to Josh McCann, an associate professor of animal science at the University of Illinois at Urbana-Champaign who is part of the Springfield project, protein is one of the most expensive macromolecules in feed. If algae proves to be competitive in price with more well-known feeds, then it may be a cheap but quality choice for breeders.
McCann notes that since the animal is one of the least picky consumers, the question is not whether the animals will consume algae. It is more about whether it is possible to produce algae at a low enough price for the food they provide. McCann hopes the unique approach of this growing project will offset some of these challenges. By creating a protein-rich alternative, raw materials for algae may be able to displace soy and other traditional ingredients that require a disproportionately large amount of land and water to grow. Researchers expect their first harvest this spring, after which McCann will conduct an analysis to assess the nutrient levels in the algae and the appropriate price for agricultural sales.
Meanwhile, the cost remains a cumbersome factor for algae-based biofuels. Estimates fluctuate depending on the manufacturer and scale, but so far nothing can compete with the current national average of $ 3.53 per gallon of gasoline at the pumps. One project Seaweed Industrialization Consortium at Duke University, is trying to produce biofuels from algae for $ 5 a gallon on a commercial scale.
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Although there is no convincing evidence that biofuels from algae emit less greenhouse gases than fossil fuels, their net carbon dioxide product is less than traditional fuels. One kilogram of algae consumes about 1.8 pounds of carbon dioxide for growth; for comparison, a mature tree absorbs about 22 pounds of carbon dioxide per year. In addition, photosynthetic organisms do not need fresh water or arable land for growth, which reduces the demand for increasingly scarce natural resources.
But before they can produce biofuels, tiny droplets of oil found in algae need to be collected. According to Manning, these cells are about 10 microns or 0.001 millimeters wide.
“Here we understand the little things. We are looking for tiny little cells, and we are looking for tiny droplets of oil that exist in these cells, ”she says. “And so we have a lot of variation in algae oil production, ranging from 15 to 50 percent oil [per organism]».
Sometimes to increase these lipid stores, algae are exposed to stress or starvation, which leads to increased oil yield. Manufacturers can raise levels by holding back nutrients such as sulfur and nitrogen, or by increasing temperature and light. Specific species of algae also play a role.
All of this says that the great experiment (s) will continue. While the US for decades crafted with industrial grade algae, the recent push from BETO adds new relevance to the field. “Algae technology provides not only an exceptional carbon sink, but also a versatile material that offers solutions to fuel-to-plastic resistance,” said the Office of Energy Efficiency and Renewable Energy. said in a press release about the recent flow of grants. But until the costs go down, these ideas will linger in labs and ponds during races – and nothing more.