[Question] High Emission Results in SUMO Intersection Simulation

[usamael2000]

I am simulating a single intersection in SUMO, and the emission results appear unusually high. I’m uncertain if there is an issue with my configuration and would appreciate any guidance on what might be going wrong.

In the SUMO configuration file, I included:

<Emissions>
    <device.emissions.probability value="1.0" />
</Emissions>

Additionally, I used an edge emissions file (additional file):

<edgeData id="emissions01" type="emissions" excludeEmpty="true" file="output/edge_emissions.xml" begin="900" end="4500" aggregate="true" edgesFile="emissions_edge_list.txt" />

For vehicle emissions, I specified emissionClass="HBEFA3/PC_G_EU4", a time step of 0.10, and a total demand of 4000 vehicles.

The resulting emission values are:

• CO2_abs = 531,906,666.25 mg = 531.91 kg
• CO_abs = 14,869,879.95 mg = 14.87 kg

Any advice on adjustments or potential issues would be greatly appreciated. Thank you!

SUMO-version: Eclipse SUMO sumo Version v1_21_0+0689-19ccfbcaee0

operating system: Debian GNU/Linux trixie x86_64

[usamael2000]

Here you are more results:

[namdre]

• stop and go at a busy intersection burns a lot more fuel than steady driving
• if you insert vehicles with the default speed of 0, this costs extra fuel (whereas realistically, cars would arrive in a small scenario with non-zero speed)
• whether the values are realistic or not cannot be answered without knowing the total distance being driven

[usamael2000]

Thanks for your replay.

I am simulating an unsignalized superstreet intersection (Reduced Left-Turn Conflict Intersection, or RCUT) as shown in the attached plot.

• The distance between the main intersection and the U-turn crossovers is 200 meters.
• The total simulation time is 1.5 hours. I discard the first and last 15 minutes, so the results reflect only the middle hour of simulation.
• In other words, the simulation loads 4000 vehicles over 1.5 hours, and I analyze results for 2666 vehicles within the one-hour timeframe.

Below is the output from the statistics file:

<?xml version="1.0" encoding="UTF-8"?>
<statistics xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="http://sumo.dlr.de/xsd/statistic_file.xsd">
    <performance clockBegin="1731437274.52" clockEnd="1731437374.16" clockDuration="99.63" traciDuration="0.00" realTimeFactor="54.20" vehicleUpdatesPerSecond="0.00" personUpdatesPerSecond="0.00" begin="0.00" end="5400.00" duration="5400.00"/>
    <vehicles loaded="4002" inserted="4002" running="73" waiting="0"/>
    <teleports total="0" jam="0" yield="0" wrongLane="0"/>
    <safety collisions="0" emergencyStops="0" emergencyBraking="0"/>
    <persons loaded="0" running="0" jammed="0"/>
    <personTeleports total="0" abortWait="0" wrongDest="0"/>
    <vehicleTripStatistics count="4002" routeLength="1256.59" speed="12.75" duration="100.47" waitingTime="3.56" timeLoss="8.23" departDelay="0.01" departDelayWaiting="0.00" totalTravelTime="402094.90" totalDepartDelay="49.30"/>
    <pedestrianStatistics number="0" routeLength="0.00" duration="0.00" timeLoss="0.00"/>
    <rideStatistics number="0"/>
    <transportStatistics number="0"/>
</statistics>

Since this is my first time working with emissions, I am uncertain whether the emission results appear reasonable.

Best regards,

[namdre]

I'd rate the results as reasonable. If you want to get a better intuition about the results, look at fuel consumption. Note, that the default output is in mg and you can set option --emissions.volumetric-fuel if you'd rather have it it ml.

[usamael2000]

Thanks for taking the time to answer my question.