Burning Biomass: Create your Own Energy

Transcription

1 Why do I care? Just imagine ONE MORNING with no energy resources available. You wake up and try to turn the light on in your bedroom. You flip the switch, but it stays dark. So you pick out your outfit in the dark, then stumble into the bathroom to hop in the shower, but the water is freezing cold. Girls, you can t straighten your hair because your iron won t turn on, and boys, no more video games while you re waiting for the bus. But you re STARVING! You go to the fridge to grab milk for your cereal, but the milk has gone bad because the refrigerator won t stay cold without power. You settle for a pop tart but then realize your toaster won t turn on so it s going to be a cold pop tart for breakfast as you walk to school with no shower, bad hair and miss matched socks. What an awful day! And that s just the first few hours of the morning! This nightmare could be ALL DAY, EVERY DAY if we run out of nonrenewable energy resources before we find an effective renewable energy resource. Did You Know? Energy is defined as the ability to do work. We use energy for day-to-day activities like walking and lifting. But we also use different types of energy to power our vehicles and provide electricity for our homes. Currently our predominant energy resources are oil and coal; these are nonrenewable resources, meaning they will eventually run out. In order to continue driving our cars and turning on our lights, we need to find sources of energy from renewable resources, which can be replenished naturally through the passage of time. Biomass, a renewable energy source, is derived from living, or recently living organisms such as plants. The neat thing about plants is that they receive their energy from the sun through photosynthesis. We just take the energy that the plants have collected and put it through processes to extract and use the stored energy. One example of energy created from biomass is ethanol. Ethanol can be made from crops like corn, grasses, and trees. Sugars within these plants can be utilized by yeast and combined with other additives to create a cleaner transportation fuel when compared to gasoline. In addition to alternative fuels, biomass can be substituted for coal to produce electricity. Burning biomass instead of coal for electricity produces fewer harmful gas emissions that can eventually lead to problems like global warming and acid rain. Examples of biomass that could be used for electricity production are crop residues, like corn stalks, and grasses. 1

2 Get With the Lingo See if you can find the following definitions in the Did You Know section on pages 1 and 2. Then use this knowledge to complete the word puzzle before starting your experiment. Biomass Renewable Resources Nonrenewable Resources Corn Heat Energy Ethanol Energy Switchgrass Coal Marginal Land Crop Land Food For Thought What would you miss most if we ran out of energy resources? Write your answers below. One thing energy producers must consider when using biomass for energy production is its impact on food production. Crops such as corn are normally grown on crop land, land that is suitable for most crops. However, certain biomass crops like switchgrass can grow on unproductive ground. This type of land is called marginal land. It s better to use biomass crops that grow on marginal land so that meeting our energy needs doesn t negatively impact food production. In this experiment, your mission is to find out how switchgrass compares to other biomass options when it comes to its potential as an energy crop. We can measure this through heat energy: a form of energy that can be measured by the amount of heat released by a substance when burned. If switchgrass gives off an adequate amount of heat energy compared to other biomasses, is a renewable resource, and can be grown on marginal lands, then it definitely has potential as an energy crop. The question is: how much energy does each biomass give off? We ll figure this out by burning the same amount of each sample under a test tube of a consistent amount of water. The change in temperature caused by the burning of each sample will tell us how much energy it s giving off. 2

3 Materials Materials Included: 0.5 g Switchgrass 0.5 g Pine Shavings 0.5 g Shredded Paper 3 Small AluminumTrays Materials Not Included: 15 ml water (H 2 O) 3 Test Tubes Liquid Thermometer Metal Stirring Stick Stick Lighter 1 Beaker (or other heat safe surface upon which to place aluminum tray) Activity Procedure: 1. Gather materials and set to the side. 2. Place beaker upside down on flat surface and place aluminum tray on top, letting the tray hang off the edge enough to gain access to the bottom. 3. Fill test tube with 5 ml H 2 O. And hold it off to the side 4. Measure and record the initial temperature of the H 2 O in the table below. Then add 0.5 g of switchgrass to the aluminum tray. 5. Use stick lighter to heat the bottom of the aluminum tray for 20 seconds. 6. Place flame to biomass until it ignites. Then place test tube back in the stand. 7. Hold test tube 1 above flame using a test tube holder. (Note: if the fire dies before biomass is mostly burned, relight as quickly as possible and continue to hold water above flames in order to transfer maximum amount of energy). *Caution: Tray will be very hot. 8. Use metal stirring stick to gently stir sample until contents are consumed by fire. Measure and record final temperature of H 2 O. Then, weigh and record the final weight of what is left of the biomass. 9. Repeat steps 1-8 using the pine shavings and then the shredded paper, then complete the chart below. 3

4 REsults Switchgrass Pine Shavings Shredded Paper Other/ Optional Biomass Initial Temp. (Temp. A) Final Temp. (Temp. B) Temp. Change ( ) (Temp. B - Temp. A) Initial Mass (Mass A) Final Mass (Mass B) Mass Change ( ) (Mass B - Mass A) Heat Energy ( Temp/ Mass) To calculate the Temperature Change ( ), subtract the Initial Temp. from the Final Temp.. To calculate the Mass Change ( ), subtract the Initial Mass from the Final Mass. It should be a negative number because mass was lost in the burning process. To calculate Heat Energy, Divide the Temp. Change ( ) by the Mass Change ( ). The BioEnergy Activity Module (BEAM) Initiative is a project of Eastern Kentucky University s Center for Renewable and Alternative Fuel Technologies (CRAFT) and is funded in whole or in part by the Appalachian Regional Commission. 4

5 Unscramble! 1. noaehlt: Discussion 1. How does switchgrass compare to the other energy sources you tested? 2. acol: 3. rcop adnl: 4. geyern: 5. icssrgswtha: 6. msaoibs: 2. The heat energy of coal is greater than the various forms of biomass provided for this activity, but renewable biomass, like switchgrass, offers some advantages over coal. Name at least three. 7. onrc: 8. etah ergyen: 9. wbeeerlna sourrcese: 10. mrgalain nlad: 11. eownnelrenba osesrercu: EKU Answers: marginal land; 11. nonrenewable resources. 8.heat energy; 9. renewable resources; hswitchgrass; 6. biomass; 7. corn; coal 3. crop land; 4. energy; 1. ethanol; Complete the chart below by graphing your results from the table on page 3. Temp (degrees) Temperature After Burning Biomass Switchgrass Pine Shavings Shredded Paper The BioEnergy Activity Module (BEAM) Initiative is a project of Eastern Kentucky University s Center for Renewable and Alternative Fuel Technologies (CRAFT) and is funded in whole or in part by the Appalachian Regional Commission. 5