Sources of Greenhouse Gases. 82 % of US produced Greenhouse gases is from combustion of fossil fuels (coal, petroleum products and natural gas)Transportation is the largest CO2 producing category, followed by industry, residential and commercial.Source: Energy Information Administration, National
1. Roundabouts & Emissions
2. Sources of Greenhouse Gases 82 % of US produced Greenhouse gases is from combustion of fossil fuels (coal, petroleum products and natural gas)
Transportation is the largest CO2 producing category, followed by industry, residential and commercial.
Source: Energy Information Administration, National Energy Information Center, Washington, D.C. http://www.eia.doe.gov/bookshelf/brochures/greenhouse/Chapter1.htm
4. Carbon Dioxide vs. Production type
5. Vehicular Emissions Dependent upon
Total amount of traffic (number of vehicles using the roads) and congestion
Intersection control type (signalized, stop signs, yield, or roundabouts)
Driving pattern (driver habits)
Vehicular characteristics (gasoline, diesel or hybrid cars and trucks)
6. Modern Roundabouts A Way to Reduce Both Congestion and Emissions
7. What is a Roundabout? NOT a circle
Roundabouts are smaller
Low speeds (15-20 MPH)
Entering vehicles always must yield
Entrances are angled to force vehicles to slow down
Pedestrian crosswalks are before roundabout entrance.
8. Traffic Circle vs Roundabout
9. Anatomy of a Roundabout
10. Roundabouts In General Safer
Improved access and circulation
Better for pedestrians
Smaller carbon footprint
12. Large and Busy Note the spectacular fountain.Note the spectacular fountain.
16. Unusual Cape Coral, FL
17. Roundabouts are Safer Fewer conflicts points
Lower Speeds The reasons roundabouts are safer.The reasons roundabouts are safer.
18. Vehicle Conflict Points
19. Conflict Points: Pedestrian/Vehicle
20. Based on an Australia study from their national roundabout standards. Only comparison I know of. Note the low crash rates for one lane roundabouts. Two lanes are higher because of illegal lane changing.Based on an Australia study from their national roundabout standards. Only comparison I know of. Note the low crash rates for one lane roundabouts. Two lanes are higher because of illegal lane changing.
21. No lost time at roundabouts from the yellow and all red time that you sit and wait at signals
22. Efficiency Comparison Intersection of CR520 & Phalanx Rd Monmouth County 2002 Corridor Study
2002 findings: A.M. (65 sec), P.M. (94 sec)
2010 predictions: A.M. (146 sec),
P.M. (160 sec)
Proposed Roundabout (2008 proposal)
A.M. (9.8 sec), P.M. (10.1 sec)
23. Phalanx Roundabout without right turn slip lane
24. Fewer Lanes Needed
25. Pedestrians Crossings
26. Greenhouse Gases Fewer gases, smaller carbon footprint Less idling
Smaller carbon footprint
Almost no steel, electronics for signals, etc.
27. Mountpelier, VT Roundabout at US2/US302 Intersection Study Three legged one-lane roundabout, near capacity compared to the signalized intersection.
Roundabout reduces fuel consumption by 929 gallons per day or about 440,000 gallons of fuel per year.
19.57 pounds CO2 produced per gallon of gasoline burned.
Roundabout reduces CO2 by 4,300 Tons per year.
28. Reference: Modern Roundabouts, Global Warming and Emissions Reductions By Tony Redington, New Hampshire, Office of Environmental Protection
29. NY State Study Roundabout vs. Signalized intersection
30. Roundabout Acceptance Public acceptance survey,
US Roundabouts, NCHRP 264
68 % oppose roundabouts
73 % favor roundabouts
31. The End