In this laboratory students will determine the amount of energy released from biodiesel compared to other energy sources.

• 12-oz empty, clean aluminum soft drink can with pull tab (1 per lab group)
• Ring stand and ring (1 per lab group)
• Thermometer (1 per lab group)
• Stir rod (1 per lab group)
• Matches (1 per lab group)
• Balance (1 per lab group)
• Tea light candle with metal cup and wick (2 per lab group)
• Watch glass (1 per lab group)
• 5 ml biodiesel, purchased from a local gas station (1 per lab group)
• 5 ml petroleum diesel, purchased from a local gas station (1 per lab group)
• Dropper or plastic pipette
• Lab sheet (1 per lab group)
• Cat litter or spill cleanup sand

Introduction:

1. Ask students if they can guess or recall  from prior knowledge what energy source is used the most in the United States. Allow students to offer their answers until they get to the correct answer, petroleum.
2. Petroleum alone makes up 36% of U.S. energy consumption.¹ What is petroleum primarily used for? Transportation! Gasoline, diesel fuel, heating oil and jet fuel all come from petroleum, which is refined from crude oil. Farmers and ranchers rely on petroleum to fuel tractors and other equipment, which is a major expense in the food production process. In 2013, the United States consumed an average of 18.89 million barrels of crude oil each day. That’s more than 793 million gallons— enough oil to fill more than 44,000 swimming pools every day.²
3. Crude oil is not considered renewable because it takes so long to replenish. So how does renewable fuel, like biodiesel, compare to petroleum diesel? In this lab, students will compare the effectiveness of biodiesel and petroleum diesel.

Laboratory:

1. Review safety procedures with class. DO NOT use burners with this exercise, due to the flammability of the fuel being tested. Maintain control of matches used in exercise.
2. Break students into lab groups.
3. Distribute lab sheet, which contains step-by-step directions.
   • Note: Lab procedure is adapted and reprinted with permission from Energy Foundations for High School Chemistry, Copyright © 2013, American Chemical Society.

Conclusion:

1. Collect lab sheets or have students complete as homework and submit the following day.
2. Ask students to momentarily assume the role of a Farm Advisor. Considering what you know now, what advice would you give to farmers who are interested in using biodiesel? Why? Students can respond by journal writing or discussing.
   • Optional Extension: Have students create a sales poster for biofuel that appeals to farmers. Students should consider all information farmers would need to know in order to make a decision to purchase biofuel.

1. U.S. energy consumption by energy source, 2012. (2012, January 1). Retrieved October 14, 2014, from http://www.eia.gov/
2. FAQ - How Much Oil is Used in the United States? (2014, May 13). Retrieved October 16, 2014, from http://www.eia.gov/tools/faqs/faq.cfm?id=33&t=6

This lab procedure is adapted and reprinted with permission from Energy Foundations for High School Chemistry, Copyright © 2013, American Chemical Society. This lesson was funded by the United States Department of Agriculture’s National Institute of Food and Agriculture, Secondary Agriculture Education Challenge Grants Program. The high school unit STEM Connections - Energy and Agriculture - Careers in Sustainable Energy was created to foster an appreciation for agriculture, reinforce STEM skills, and create an awareness of agriculture-related careers in students while meeting the needs of California’s teachers.