Youth explore biofuel as renewable energy

Youth can explore biofuel at 4-H Renewable Energy Camp and through other 4-H science programs.

Fossil fuels have been the primary source of transportation fuel in the United States for years. However, increasing concerns about greenhouse gases and energy security led to increased funding for research and production of biofuels. Congress created the Renewable Fuel Standard program as part of the Energy Policy Act of 2005, which was expanded under the Energy Independence and Security Act in 2007.

The Energy Independence and Security Act of 2007 calls for 36 billion gallons of renewable fuels by 2022. According to Michigan State University Extension’s bioenergy and bioproducts team, the United States produced 13.9 billion gallons of ethanol from corn grain in 2011. Corn ethanol will make up 15 billion gallons; cellulosic and advanced biofuels will make up the remaining 21 billion gallons.

You can help youth explore biofuels by guiding them through an activity that shows how organic materials can be converted to fuel. Cellulose and sugars in plants when combined with an enzyme found in yeast can be used to create ethanol, a common biofuel, and the gas carbon dioxide.

Sugar + Enzyme Found in Yeast = Ethanol + Carbon Dioxide

Provide each pair of youth with three clean, empty, 20-ounce bottles; three packets or 3 tablespoons of yeast; warm water; three 9-inch balloons; measuring tape; a funnel; and 3 tablespoons each of three sources of sugar, such as table sugar, corn meal, crushed dried leaves, mashed fruit or other plant material. In each bottle, add one packet or 1 tablespoon of yeast and one source of sugar. Then, fill each bottle half-full with warm water, put the cap on and shake well. Next, remove the cap and quickly cover the opening with a balloon. Place in a warm location and record the circumference of each balloon after 10 minutes and again after one hour. If possible, leave for a couple of days, recording the circumference of each balloon daily along with other observations. Remember, as the enzyme converts the plant matter into ethanol, it is releasing carbon dioxide (CO2).

Which balloon inflated the most? Could that tell you something about the amount of ethanol made? Why do you think some sugar sources produced more CO2? Do you think some sugar sources have more fuel to react with the yeast? What do you think would happen if you added more yeast with the same amount of sugar? Why do you think you need warm water? Would it work with cold water?

The process observed in the experiment is the process of fermentation. The enzyme in the yeast breaks down sugar molecules, producing ethanol and CO2. Even though CO2 is a greenhouse gas, this is not a problem. The CO2 produced will be used to grow the next crop of plants to produce the next round of ethanol.

Ethanol and biodiesel are biofuels that are made from biomass materials. These fuels are usually blended with petroleum fuels, but they can be used on their own. Ethanol is an alcohol fuel primarily made from the sugars found in corn. Biodiesel is produced from vegetable oils, fats or greases, such as recycled restaurant grease. Both are nontoxic and biodegradable. Scientists are working on ways to make ethanol from biomass, which includes all parts of a plant rather than just grain. Plant examples include miscanthus, switchgrass, corn, poplar, sugarcane and palm oil.

For more opportunities for youth to explore biofuels and renewable energy, check out the 4-H Renewable Energy Camp held each July through Michigan State University Extension or the Biofuel Blast National 4-H Science Experiment.

Michigan State University Extension and the Michigan 4-H Youth Development program help to create a community excited about STEM (Science, Technology, Engineering, and Mathematics). 4-H STEM programming seeks to increase science literacy, introducing youth to the experiential learning process that helps them to build problem-solving, critical-thinking and decision-making skills. Youth who participate in 4-H STEM content are better equipped with critical life skills necessary for future success. To learn more about the positive impact of Michigan 4-H youth in STEM literacy programs, read our 2015 Impact Report: “Building Science Literacy and Future STEM Professionals.”

Did you find this article useful?