Introduction
This page is the compilation of a research project in partnership between Engr308 Technology and the Environment and the Humboldt State University The Sustainability Office during Fall 2018. The client leads on this project are
- Megan Tolbert, Waste, Recycling and Grounds Coordinator
- Katie Koscielak, Sustainability Analyst
The objective of this project is to analyze and compare the effects of the impacts of various types of straws based upon their embedded carbon dioxide emissions, and embedded energy. A secondary goal is to create a recommendation that would educated future straw policy. Another goal was to create compelling straw comparisons for consumers.
Findings
This study of plastic straws, stainless steel straws, glass straws, paper straws, and bamboo straws compared three metrics: carbon dioxide emissions, embedded energy, and cost. It was concluded that the materials used, transport of, and disposal of a single plastic straw requires 27.2 kJ of energy, is responsible for 1.46 grams of carbon dioxide emissions, and are sold for $0.003. In comparison, a single stainless steel straw is responsible for using 2420 kJ of energy, releasing 217 grams of carbon dioxide, and costs $3.00. A single glass straw is responsible for using 1105 kJ of energy, releasing 65.2 grams of carbon dioxide emissions, and costs $0.32. A single paper straw is responsible for using 15.1 kJ of energy, releasing 1.38 grams of carbon dioxide emissions, and costs $0.04. A single bamboo straw is responsible for 754 kJ of energy, releasing 38.8 grams of carbon dioxide emissions, and costs $1.29. In order to abate the embedded energy and carbon dioxide emissions incorporated in a stainless steel straw, glass straw, and bamboo straw, the stainless steel straw must be reused 102 times (energy) and 149 times (carbon dioxide), the glass straw must be reused 45 times to make up for both embedded energy and carbon dioxide, and the bamboo straw must be reused 32 times (energy) and 27 times (carbon dioxide), rather than purchase and dispose of a plastic straw.
Plastic Straw | Stainless Steel Straw | Glass Straw | Paper Straw | Bamboo Straw | |
---|---|---|---|---|---|
Embedded Energy (kJ/straw) | 23.7 | 2420 | 1074 | 16.0 | 756 |
Carbon Dioxide (gCO2/straw) | 1.46 | 217 | 65.2 | 1.38 | 38.8 |
Straw Reuses Needed to pay off EE | Disposable | 102 | 45 | Disposable | 32 |
Straw Reuses Needed to pay off CO2 | Disposable | 149 | 45 | Disposable | 27 |
The calculations and assumptions used to obtain these results can be seen in further detail in the following spreadsheet:
The spreadsheet allows for others interested in performing a similar analysis to easily input values pertaining to their particular study area. It is our hope that with this information and the pre-assembled spreadsheet, other institutions will be able to reach similar compelling conclusions that have the potential to influence future policies.
Plastic Straws
The plastic straws analyzed in this study were the Straight Straws made of polypropylene weighing 0.20 grams. The straws were produced by the company Plastico based out of Surrey, United Kingdoms, and were transported to Humboldt State University in Arcata, California. The jars are purchased by the pallet for $0.003 per straw. It was estimated that about 100% of all the straws purchased were thrown out.
Output | Embedded Energy | Carbon Dioxide Emissions |
---|---|---|
Materials | 20.17 kJ/straw | 1.10 g CO2/straw |
Transportation | 6.99 kJ/straw | 0.34 g CO2/straw |
Disposal | 0.02 kJ/straw | 0.01 g CO2/straw |
Total | 27.18 kJ/straw | 1.45 g CO2/straw |
Stainless Steel Straws
The stainless steel straws analyzed in this study were the Stainless Steel Drinking Straws weighing 10 grams. These straws were produced by the company Santi Sora based out of Guangdong, China, and were transported to Humboldt State University in Arcata, California. The straws are purchased by the pallet for $0.26 per straw. It was estimated that 3% of all the stainless steel straws purchased were thrown out within 5 years of acquiring the straw.
Output | Embedded Energy | Carbon Dioxide Emissions |
---|---|---|
Materials | 820.00 kJ/straw | 140.91 g CO2/straw |
Transportation | 1598.92 kJ/straw | 76.24 g CO2/straw |
Disposal | 0.02 kJ/straw | 0.02 g CO2/straw |
Total | 2418.94 kJ/straw | 217.16 g CO2/straw |
Glass Straws
The glass straws analyzed in this study were the 8" Simple Elegance straws weighing 21.3 grams. These straws were produced by the company Glass Dharma based out of Fort Bragg, California, and were transported to Humboldt State University in Arcata, California. The straws are sold by the four pack for $7.99 per straw. It was estimated that 10% of all the glass straws purchased were recycled within 5 years of acquiring the straw.
Output | Embedded Energy | Carbon Dioxide Emissions |
---|---|---|
Materials | 834.06 kJ/straw | 49.29 g CO2/straw |
Transportation | 271.32 kJ/straw | 15.78 g CO2/straw |
Disposal | 0.50 kJ/straw | 0.08 g CO2/straw |
Total | 1105.88 kJ/straw | 65.15 g CO2/straw |
Paper Straws
The paper straws analyzed in this study were the 7.75" White Jumbo Paper straws weighing 0.20 grams. These cups were produced by the company Aardvark Straws based out of Fremont, California, and were transported to Humboldt State University in Arcata, California. The straws are purchased by the case for $0.04 per straw. It was estimated that 100% of all the paper cups purchased were thrown out.
Output | Embedded Energy | Carbon Dioxide Emissions |
---|---|---|
Materials | 3.61 kJ/straw | 0.53 g CO2/straw |
Transportation | 11.43 kJ/straw | 0.85 g CO2/straw |
Disposal | 0.01 kJ/straw | 0.01 g CO2/straw |
Total | 15.05 kJ/straw | 1.38 g CO2/straw |
Bamboo Straws
The bamboo straws analyzed in this study were the 8.9" Bamboo straws weighing 3.6 grams. The straws were produced by the company Bali Boo based out of Bali, Indonesia, and were transported to Humboldt State University in Arcata, California. The straws are purchased by the 100 for $1.29 per straw. It was estimated that 25% of all the bamboo straws purchased were composted and 25% were thrown out within 5 years of acquiring.
Output | Embedded Energy | Carbon Dioxide Emissions |
---|---|---|
Materials | 9.10 kJ/straw | 0.55 g CO2/straw |
Transportation | 745.23 kJ/straw | 38.27 g CO2/straw |
Disposal | 0.07 kJ/straw | 0.05 g CO2/straw |
Total | 754.41 kJ/straw | 38.87 g CO2/straw |
Impacts
- THIS PORTION OF THE PAGE HAS NOT BE UPDATED TO CONTAIN RELEVANT STRAW ANALYSIS INFORMATION. IT CONTAINS THE PREVIOUS MASON JAR ANALYSIS.**
Based off the calculations made above for the embedded energy, CO2 emissions, and costs relating to each beverage container, various impacts on the HSU campus can be made. On a typical work day at HSU (Monday through Friday), it can be assumed that:
- Mason jars: 75 jars sold
- Paper cups: 100 cups sold
- Plastic cups: 75 cups sold
- Re-Usable Containers: 500 drinks sold
Given that there are 146 work days in a year, the impacts below can be calculated:
Total Sold | Embedded Energy | CO2 Emissions | |
---|---|---|---|
Mason Jar | 10,950 jars | 18,558 kWh | 5,132 kg |
Paper Cups | 14,600 cups | 3,806 kWh | 754 kg |
Plastic Cups | 10,950 cups | 2,961 kWh | 375 kg |
In terms of the savings from the 500 refills, and assuming that the same ratio of paper and cups sold are now being avoided in those reusable refills, it can be said that:
Total Saved | Embedded Energy Savings | CO2 Emissions Avoided | |
---|---|---|---|
Paper Cups | 41,714 cups | 10,875 kWh | 2,154 kg |
Plastic Cups | 31,286 cups | 8,460 kWh | 1,070 kg |
Total | 73,000 cups | 19,335 kWh | 3,224 kg |
The cost of 500 Mason jars equates to 847 kWh of embedded energy, and 234 kg CO2 emissions.
In total, this presents a savings of 18,488 kWh of energy, and 2,990 kg of CO2 avoided.
In addition, the value of 19,335 kWh saved outweighs the embedded energy in all of the mason jars purchased. So even if all of those mason jars purchased were single use, the savings would outweigh their embedded energy of 18,558 kWh. The same thing is not true for the embedded CO2. That said, the mason jars are not being used just once which makes mason jar implementation much more compelling.
Comparisons
A number of comparisons have been made by each team which help understand the magnitude of the impacts of the policy change being analyzed in this report. These comparisons are represented as one or two lines of text on a relatable image, and are displayed in the gallery link below. **Need to create comparisons page for straws.
Research Synthesis
Embedded Energy, CO2, and Life Cycle Analysis Concepts
During the spring of 2016, Humboldt State University chose to support the Kill the Cup Campaign, a national campaign to end the use of disposable coffee cups and to promote the use of reusable cups. After the Campaign ended, Waste Reduction and Resource Awareness Program (WRRAP), Zero Waste Humboldt, and Humboldt State University’s Dining services decided to sell Mason Jars as a way to promote the use of reusable cups. They are sold along side paper cups, but by reusing a mug instead of purchasing a paper cup, the coffee would costs less. This literature review, will go over the embedded energy and CO2 emissions of the individual products, the energy and carbon impact of shipping the products, and disposal of the products, as well as creating a total energy and carbon dioxide impact of the product once the product is bought.
Embodied or embedded energy (EE) is defined as the energy used during the entire life cycle of a product. For example, the EE of a mason jar or a disposable cup could include extraction and processing of raw materials, manufacturing, transportation, distribution, use, reuse, recycling and final disposal. EE calculations are used to conduct life cycle assessments (LCA). LCA is a well-explored concept and has been used as an environmental management tool since the late 1960’s.[1] LCA provides a tool for evaluating the relative environmental impact of various materials and calculates externalities otherwise excluded from pricing. Our LCA will include emissions and the EE of the materials and shipping.[2]
Some background information:
Embedded Energy and CO2 Emissions in materials
Mason Jars
Material | Embedded Energy (MJ/kg) | CO2 Emissions (kg CO2/kg) |
---|---|---|
Soda-Lime | 11 | .8 |
Float Glass | 15.511 | 1.136 |
Primary Glass | 15.00 | .86 |
Secondary Glass | 11.50 | .55 |
Fiberglass | 28.00 | 1.54 |
Toughened | 23.50 | 1.27 |
"Not recycled: 8.4 kg CO2E per kilogram of glass
Recycled : 1.4 kg CO2E per kilogram of glass" [5]
Stainless steel lid: 56.7 MJ/kg (EE), 6.15 (CO2E) [6]
Paper Cups
- Paper: 25.66 (Mj/Kg), 1.29(kg CO2/kg)[7]
- Glue: EE 61.67 MJ/kg; CO2E 1.3 kgCO2/kg
- Lid (polycarbonate): EE 112.9 MJ/kg; CO2E 7.62 kgCO2/kg
- Sleeve: EE 29.97 MJ/kg; CO2E 1.29 kgCO2/kg
Plastic Cups
Polylactide Plastic: EE 54.1 (Mj/Kg); CO2E 1.8 (kg CO2/kg) [8]
Embedded Energy and CO2 Emissions in Transportation
Transport by sea [9]
- 6,000 TEU Container Ship: Embedded Energy: 0.143 MJ/t/km
- 6,000 TEU Container Ship: CO2Emissions: 11.1 g/t/km
- 1,500,000 ton bulk carrier: Embedded Energy 0.027 MJ/t/km
- 1,500,000 ton bulk carrier: CO2 Emissions 2.1 g/t/km
Transport by Land
For Trucks the Fuel efficiency of Class 8 Truck by Vehicle Weight Range on Flat Terrain at 65 mph 9.2 miles/gal [10] which we then convert into km which is 14.8 km/gal.
- For Diesel Fuel
Energy intensity: 135.8 MJ/gal[11]
Carbon Intensity 10.15 kg CO2 /gal [12]
- General embedded energy in shipping by land [13]
traveled by truck: 2.7 MJ/ t-km
Traveled by Truck: 180 (t CO2E / t-km x 10^6)
General embedded CO2 in shipping by land 80 g/tonne/km[16]
Embedded Energy and CO2 Emissions in Disposal
It was found that Humboldt State University sends it's waste to landfills at Redding, CA and at Medford, OR [17]
Humboldt State also sends their Recyclable waste to Willits, CA [18] and to Strategic Material in San Leandro, CA
The efficiency for a variety of trash trucks was averaged at 3 miles per gallon which was then converted to km instead of miles[19] which ended being 4.8 km/gal.
Diesel Energy intensity: 135.8 MJ/gal[20]
Carbon Intensity 10.15 kg CO2 /gal [21]
Next Steps
After completing the initial analysis, there are various alterations to the methods that could be made to create even more accurate results. These include:
- What are people's methods of washing the straws? Is it significant enough to change the final outputs?
- How often are straws actually reused compared to the number that are purchased simply due to the lower price?
- Determine the volume of waste avoided by the implementation of a policy such as this.
- Calculate the embedded energy and carbon dioxide emissions in each unit produced by the manufacturing facilities, and the acquisition of the raw materials.
- Explore alternate options as to whether or not other viable products have the potential to reduce the embedded energy or carbon dioxide emissions from any of the straws.
- Determine outlets for promoting and distributing this research to make it widely accessible.
- Partnership with other CSUs to strive towards waste, energy, and CO2 reduction initiatives.
References
- ↑ Menzies, Gillian F., Seyhan Turan, and Philip FG Banfill. "Life-cycle assessment and embodied energy: a review."Proceedings of the Institution of Civil Engineers-Construction Materials 160.4 (2007): 135-144
- ↑ http://buildingsdatabook.eren.doe.gov/TableView.aspx?table=Notes/
- ↑ Ashby, M. (2012). Materials and the Environment - Eco-informed Material Choice.
- ↑ http://www.viking-house.co.uk/downloads/ICE%20Version%201.6a.pdf
- ↑ http://www.greenrationbook.org.uk/resources/footprints-glass
- ↑ http://www.viking-house.co.uk/downloads/ICE%20Version%201.6a.pdf
- ↑ https://www.dartcontainer.com/media/1889/ilea.pdf
- ↑ http://www.natureworksllc.com/~/media/The_Ingeo_Journey/EcoProfile_LCA/EcoProfile/NTR_CompleteLCA_EcoProfile_1102_pdf.pdf?la=en
- ↑ http://www.sname.org/HigherLogic/System/DownloadDocumentFile.ashx?DocumentFileKey=8fc28849-71a2-4f98-886f-7b5e7b8819a8
- ↑ http://cta.ornl.gov/vtmarketreport/pdf/chapter3_heavy_trucks.pdf
- ↑ https://www.extension.iastate.edu/agdm/wholefarm/pdf/c6-87.pdf
- ↑ http://www.eia.gov/tools/faqs/faq.cfm?id=307&t=11
- ↑ http://pubs.acs.org/doi/pdf/10.1021/es702969f
- ↑ http://cta.ornl.gov/data/chapter2.shtml
- ↑ http://www.dot.ca.gov/trafficops/trucks/quickguide.html
- ↑ http://www.ics-shipping.org/docs/co2,
- ↑ https://humboldtgov.org/DocumentCenter/View/4203
- ↑ http://www.northcoastjournal.com/humboldt/the-recyclable-journey/Content?oid=2166785
- ↑ http://www.cert.ucr.edu/events/pems2014/liveagenda/25sandhu.pdf
- ↑ https://www.extension.iastate.edu/agdm/wholefarm/pdf/c6-87.pdf
- ↑ http://www.eia.gov/tools/faqs/faq.cfm?id=307&t=11