OPTIMIZING CONGESTION
CHARGE UNIT VALUES
Olavi H. Koskinen Finnish Road Administra7on P.O. BOX 33 FI-­‐00521 HELSINKI phone +358 20 422 2502 fax +358 20 422 231 e-­‐mail ohk@finnra.fi CONGESTION VS. EMISSIONS
-­‐ In large ci7es in the world traffic is congested -­‐ Conges7on is equal to engine opera7on in transient state -­‐ Increased fuel consump7on and emissions -­‐ Environmental problems PRICING OF EMISSIONS
-­‐ In many countries emissions have shadow unit prices for socio-­‐economic analysis -­‐ Emission “costs” can be es7mated by these unit values and emission amounts -­‐ Hence conges7on can also be priced FUEL TAX
-­‐ In Western European countries an essen7al part of fuel price is tax -­‐ Increased accumulated fuel tax in congested condi7ons covers excellently conges7on ‘costs’ -­‐ Fuel tax is economic and efficient way to collect ‘conges7on charges’ -­‐ No other systems are needed -­‐ However, fuel tax level must be appropriate -­‐ In European Union fuel tax level is appropriate NO FUEL TAX OR FUEL TAX
NEGLIGIBLE
If conges7on will be charged according to cost responsibility (real emission amounts and predefined unit prices), -­‐ no exis7ng collec7on systems, neither manual nor automa7c can do this -­‐ simula7on based on engine maps and vehicle dynamics can be u7lized in solving this problem USING SIMULATION IN ESTIMATING
CONGESTION IMPACTS
-­‐ Conges7on degree can be described by target speed and average speed -­‐ These quan77es can also be censored and recognized by electric charging systems -­‐ Impacts of conges7on degree on emissions and fuel consump7on are determined by vehicle mo7on simula7on -­‐ Conges7on pricing for different vehicle categories is based on previous impacts and shadow unit prices of emissions CASES TO BE STUDIED (1)
Route -­‐ Ring road 3 in Helsinki area -­‐ Target speed is 100 km/h for passenger cars, vans and coaches -­‐ Target speed is 80 km/h for all truck types -­‐ Conges7on degree varies between 0 and 87 percent CASES TO BE STUDIED (2)
Vehicle categories represen7ng following type vehicles: Category Abbrevia7on Vehicle Rated engine mass power kg kW Passenger car P 1400 66 Van (light goods vehicle) V 2300 76 Coach C 16000 250 Single truck T 22000 250 Truck+semitrailer (ar7culated vehicle) TS 35000 309 Truck+trailer (road train) TT 50000 345 CASES TO BE STUDIED (3)
Current monetary unit values Gasoline Diesel fuel €/l €/l Fuel tax excluding VAT 0.627 0.364 VAT (22 %) 0.138 0.080 Fuel tax including VAT 0.765 0.444 CASES TO BE STUDIED (4)
Shadow prices for emission items: Built up areas Rural areas €/t €/t Nitrogen oxides (NOx) 1170 458 Carbon monoxide (CO) 78.61 53.84 Hydro carbons (HC) 70.20 70.20 Par7culate mamers (PM) 213000 6640 Carbon dioxide (CO2) 33.80 33.80 RESULTS (1)
Defini7on of conges7on degree p = (1 – va/vt) where: p = conges7on degree (dimensionless 0 … 1) va = average speed (=proceeded distance/used 7me[km/h] vt = target speed [km/h] conges7on degree = 0, when average speed = target speed conges7on degree = 1, when nothing moves RESULTS (2)
General form of the cost model y = C0 + C1 p + C2 p2 for light vehicles and y = C0 + C1 pC2 for heavy vehicles where: y = costs [€/km] p = conges7on degree [%] C0, C1 and C2 = model coefficients RESULTS (3)
Defini&on of conges&on costs Conges&on costs = increase of emission costs compared to driving state with conges&on degree of zero. In other words z = C1 p + C2 p2 for light vehicles and z = C1 pC2 for heavy vehicles where: z = conges&on costs [€/km] p = conges&on degree other symbols as above RESULTS (4)
Coefficients for emissions costs VEH.
CAT
FUEL TAX
EMISSIONS COSTS
EMISSION COSTS
built up areas
rural areas
C1
C2
C1
C2
C1
C2
P -.000115754 .000006809 -.000041682 .000001194 -.000040050 .000001152
V -.000140871 .000006682 -.000007351 .000000735 -.000009183 .000000675
C .000057262 1.6675
.000025110 1.5816
.000016543 1.6262
T .000161741 1.5386
.000024467 1.6791
.000028563 1.6017
TS .000243751 1.5104
.000044066 1.6046
.000046565 1.5531
TT .000888445 1.2527
.000000673 2.7761
.000116849 1.3820
RESULTS (5)
The results can be seen in the figures according to the next list: Fuel tax and emission costs vs. conges7on degree Fig.1 Passenger car Fig. 2 Van (light goods vehicle) Fig. 3 Coach Fig. 4 Single truck Fig. 5 Truck + semi-­‐trailer (ar7culated vehicle) Fig. 6 Truck + trailer (road train) Fig. 7 All type vehicles PASSENGER CAR
VAN (LIGHT GOODS VEHICLE)
COACH
SINGLE TRUCK
TRUCK + SEMI-TRAILER
TRUCK + TRAILER
ALL TYPE VEHICLES
CONCLUSIONS (1)
-­‐ Vehicle mo&on simula&on is an efficient way to determine correct unit values of conges&on charges for different vehicle types -­‐ Costs caused by the system itself (investment, opera&on and administra&on) must be included in these unit prices, too -­‐ However, fuel tax, where it is applied, is more efficient and economic way to collect conges&on charges -­‐ Very good rela&onship between conges&on costs and fuel tax accumula&on CONCLUSIONS (2)
For light vehicles (passenger cars and vans) op7mum is not reached at conges7on degree 0 % Op7mum for light vehicles Fuel tax Emission costs Emission costs accumula7on built up areas rural areas cong. avg. cong. avg. cong. avg. deg. speed deg. speed deg. speed % km/h % km/h % km/h Passenger car 8.5 91.5 17.5 82.5 17.4 82.6 Van 10.5 89.5 5.0 95.0 6.8 93.2 CONCLUSIONS (3)
For light vehicles: -­‐ Conges7on <> more or less work against accelera7on resistance -­‐ Conges7on <> thus more or less fuel and emissions -­‐ Work compensated efficiently by reduced work against driving resistances (rolling and air) -­‐ Op7mum found in slightly congested traffic