CHAPTER 6: SUMMARY AND FUTURE WORK
6.2 Future Work
This thesis examined waste collection vehicles during waste collection. Waste collection vehicles operate under four different operation modes: (a) urban driving, (b) waste collection, (c) freeway driving, and (d) landfill activities. Each operational mode has different speed, idling time, emissions, and breaking profiles. Texas Transportation Institute at Texas A&M University established a baseline for diesel-fueled waste collection vehicles emissions under actual operation conditions (Farzaneh et al., 2009). Two portable emissions measurement systems (PEMS) were used to measure the gaseous state emission and PM emissions from in-use refuse
58
trucks during the four different operational modes. In a future study, MOVES could be used to model Texas Sate collection vehicles to find the expected gaseous and Particulate Matter (PM) emissions under the four different operational and compare them to real data emissions. This analysis would be useful to validate the MOVES results as compared to actual emissions.
In a future study, on-board GPS devices could be used to track waste collection vehicles during their daily operational activities. GPS devices could be monitored remotely to collect driving cycle information of waste collection vehicles at different times and locations. In this approach, the speed vs. time will be generated for waste collection vehicles at different locations. Simultaneously, atmospheric conditions such as temperature will be obtained from the local weather station. Accordingly, MOVES will be used to estimate emissions for diesel-fueled waste collection vehicles using the collected data as an input.
In this study, natural gas (CNG/LNG), biodiesel, hybrid, and hydrogen fuels have a potential to be a future fuel for waste collection vehicles. However, so far MOVES does not provide data regarding emissions and fuel consumption for waste collection vehicles using these fuels. A future study could be conducted to build a database using MOVES for these alternative fuel technologies. The literature provides a good source for such data. Several examples include Texas Transportation Institute study, which investigated the emissions from Liquefied Natural Gas (LNG) and Compressed Natural Gas (CNG) waste collection vehicles under actual operating conditions (Farzaneh et al, 2009), Waste Management Inc. also conducted tests on CNG/LNG waste collection vehicles (Chandler, 2001). Several field tests were performed on the Autcar E3 hybrid refuse truck as well (Parker Corporation, 2010). This future study will implement a national model for waste collection vehicles. The model will serves as a tool to estimate the fuel
59
consumption, emissions, and travel cost for diesel-fueled waste collection vehicles as well as alternative fuels vehicles under different operating conditions.
60
61
Environmental Study of Solid Waste Collection Fuel Selection Criteria
Please rate the significance of the following factors in electing fuels used in waste collection vehicles. The rating is based on a scale of one to ten (low significance to high significance).
I. Environmental Issues. “how significant is:”
a. The air pollution and toxics emitted by the fuel:
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
b. The fuel lifecycle:
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
c. The fuel impact on water sources:
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
II. Security Issues. “how significance is:”
a. The dependence on foreign countries for fuel (ex. Middle East):
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
b. The global supplies of the fuel:
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
c. The use of renewable fuel:
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
d. The community acceptance of the fuel
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
III. Financial Issues. “how significance is:”
a. The capital cost of fuel utilization “Vehicles cost”:
1 2 3 4 5 6 7 8 9 10
62
Environmental Study of Solid Waste Collection Fuel Selection Criteria
b. The running cost of fuel utilization “Fuel cost and vehicles maintenance cost”:
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
c. Fuel Prices Stability:
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
d. Fuel infrastructures cost:
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
IV. Operational Issues. “how significance is:” a. Vehicle weight:
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
b. Operational range of the vehicle:
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
V. Safety Issues. “how significance is:”
a. The noise associated with collection vehicles:
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
b. The occupational safety associated with collection vehicles:
1 2 3 4 5 6 7 8 9 10
Low Significance High Significance
c. The fuel hazards of utilization:
1 2 3 4 5 6 7 8 9 10
63
64 Table B-1: Fuel Life-Cycle Emissions.
Fuel Category kg CO₂
Equivalent
Percentage Emission Relative to Gasoline
Gasoline 5.42 100%
LNG (Non-North America Source) 4.91 91%
LNG (North America Source) 4.77 88%
CNG (Non-North America Source) 4.59 85%
Diesel 4.58 84%
LPG 4.50 83%
E85 4.15 76%
Biodiesel (B20) 4.14 76%
CNG (North America Source) 4.09 75%
Hybrid 3.83 71%
Gaseous H2 (on-site Refueling) 3.15 58%
Biodiesel (B100) 1.10 20%
LNG (LFG) 0.19 4%
65
Table B-2: Cost Trend for Waste Collection Vehicle Travel.
Year 2008 2009 2010 2015 2020 2025 2030 2035
LPG ($/million
Btu) 30.23 25.52 27.24 30.56 32.96 34.62 35.56 35.66
Million Btu/mile 5.40E-02 5.40E-02 5.40E-02 5.40E-02 5.40E-02 5.40E-02 5.40E-02 5.40E- 02
US $/CVMT 1.63 1.38 1.47 1.65 1.78 1.87 1.92 1.93
E85 ($/million
Btu) 35.36 20.50 24.89 26.38 28.79 29.49 30.34 30.93
Million Btu/mile 5.41E-02 5.41E-02 5.41E-02 5.41E-02 5.41E-02 5.41E-02 5.41E-02 5.41E- 02
US $/CVMT 1.91 1.11 1.35 1.43 1.56 1.60 1.64 1.67
Gasoline
($/million Btu) 27.06 19.28 22.12 25.97 28.15 29.49 30.33 30.90
Million Btu/mile 5.69E-02 5.69E-02 5.69E-02 5.69E-02 5.69E-02 5.69E-02 5.69E-02 5.69E- 02
US $/CVMT 1.54 1.10 1.26 1.48 1.60 1.68 1.73 1.76
Diesel ($/million
Btu) 27.97 17.79 21.07 22.50 25.69 27.19 27.98 28.39
Million Btu/mile 4.62E-02 4.62E-02 4.62E-02 4.62E-02 4.62E-02 4.62E-02 4.62E-02 4.62E- 02
US $/CVMT 1.29 0.82 0.97 1.04 1.19 1.26 1.29 1.31
CNG ($/million
Btu) 17.20 12.71 12.04 11.97 12.25 12.84 13.14 13.57
Million Btu/mile 5.23E-02 5.23E-02 5.23E-02 5.23E-02 5.23E-02 5.23E-02 5.23E-02 5.23E- 02
US $/CVMT 0.90 0.67 0.63 0.63 0.64 0.67 0.69 0.71
Hybrid ($/million
Btu) 27.97 17.79 21.07 22.50 25.69 27.19 27.98 28.39
Million Btu/mile 3.87E-02 3.87E-02 3.87E-02 3.87E-02 3.87E-02 3.87E-02 3.87E-02 3.87E- 02
US $/CVMT 1.08 0.69 0.81 0.87 0.99 1.05 1.08 1.10
LNG ($/million
Btu) 17.20 12.71 12.04 11.97 12.25 12.84 13.14 13.57
Million Btu/mile 6.05E-02 6.05E-02 6.05E-02 6.05E-02 6.05E-02 6.05E-02 6.05E-02 6.05E- 02
66
Table B-3: Waste Collection EFs (g or KJ per mile Travel) vs. Average Speed.
Speed (mph) 5 10 15 20 25 30 35 40 45 50 Carbon Monoxide 16.23 8.21 6.67 5.46 4.90 4.46 3.90 3.66 3.47 3.25 Oxides of Nitrogen 48.69 22.23 19.61 17.44 16.06 15.51 13.47 12.93 12.50 11.95 Carbon Dioxide 5,611 2,643 2,396 2,100 1,945 1,876 1,596 1,538 1,494 1,417 Total Energy Consumption 76,515 36,035 32,673 28,637 26,524 25,585 21,767 20,980 20,367 19,322 CO2 Equivalent 5,611 2,643 2,396 2,100 1,945 1,876 1,596 1,538 1,494 1,417
Table B-4: Waste Collection EFs (g or KJ per mile Travel) vs. Road Grade.
Road Grade -20 -15 -10 -5 0 5 10 15 20
Carbon Monoxide 1.70 1.78 2.07 3.01 4.90 8.02 10.91 13.64 15.23 Oxides of Nitrogen 3.99 4.11 4.40 5.82 16.06 33.12 50.50 65.66 73.60 Carbon Dioxide 631 642 659 771 1,945 4,088 6,407 8,449 9,506 Total Energy Consumption 8,610 8,751 8,985 10,511 26,524 55,742 87,365 115,207 129,626
CO2 Equivalent 631 642 659 771 1,945 4,088 6,407 8,449 9,506
Table B-5: Noise Level Associated with Manual and Automated Waste Collection Vehicles.
Position
Distance From Waste
Collection Vehicle (ft)
Noise Dosimeter Reading (db)
Manual Truck (1) Manual Truck (2) Automated Truck (1) Automated Truck (2) Manual Trucks Average Automated Truck Average 1 -100 70.4 68.7 68.9 77.6 70 73 2 -60 80.5 86.6 75.8 79.1 84 77 3 0 85.5 93.3 84.5 84.5 89 85 4 60 80.7 85.7 75.8 75.9 83 76 5 100 68.4 70.7 68.9 68.6 70 69
67
68 Sample Calculation for Table 3-1:
( ) Sample Calculation for Table 3-2:
( ) ( ) ( ) ( ) Sample Calculation for Table 3-3:
( ) ( ) Sample Calculation for Table 3-4:
Diesel to Gasoline
69
Sample Calculation for Table 3-5: Energy Required by Conv. Gasoline Waste Collection Vehicle
=
Energy Required by CNG Waste Collection Vehicle
=
Average mpg for Conv. Gasoline Waste Collection Vehicle
Average mpDEG for Conv. Gasoline Waste Collection Vehicle
Sample Calculation for Table 3-7: Energy Required by LNG Waste Collection Vehicle ( )
Average m per ft3 for LNG Waste Collection Vehicle
70
71
University of Central Florida Institutional Review Board Office of Research & Commercialization
12201 Research Parkway, Suite 501 Orlando, Florida 32826-3246
Telephone: 407-823-2901 or 407-882-2276 www.research.ucf.edu/compliance/irb.html
Approval of Exempt Human Research
From: UCF Institutional Review Board #1 FWA00000351, IRB00001138
To: Pamela McCauley Bush and Co-PI: Debra R Reinhart
Date: February 22, 2011
Dear Researcher:
On 2/22/2011, the IRB approved the following activity as human participant research that is exempt from regulation:
Type of Review: Exempt Determination
Project Title: Ergonomic Study of Solid Waste Collection Investigator: Pamela McCauley Bush
IRB Number: SBE-11-07409
Funding Agency: Environmental Research and Education Foundation
Grant Title: N/A
Research ID: SBE-11-07409
This determination applies only to the activities described in the IRB submission and does not apply should any changes be made. If changes are made and there are questions about whether these changes affect the exempt status of the human research, please contact the IRB. When you have completed your research, please submit a Study Closure request in iRIS so that IRB records will be accurate.
In the conduct of this research, you are responsible to follow the requirements of the Investigator Manual. On behalf of Joseph Bielitzki, DVM, UCF IRB Chair, this letter is signed by:
Signature applied by Joanne Muratori on 02/22/2011 01:59:51 PM EST
72
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