Estimating volumes of air

used by enginesin an urban setting

Lewis Poulin

Canadian Meteorological Center2121 route Transcanadienne

Dorval Québec H9P 1J3email: lewis.poulin@ec.gc.ca

Overview• Part 1: Ventilation

– Volumes of air used by various processes are estimated & compared• Humans: Engines: 2-stroke, 4-stroke: Airplane Airbus 320 engine• Air consumption volumes for single engines• Applied to numbers of engines for island Montreal• Air consumption under a stagnant ridge

• Part 2: Education– A new approach to communicate air quality information

• Package impact of our actions in terms humans can relate to• Allows new types of public education tools

• Part 3: Economic implications– Basis for clean air trading system– Allows marketplace to easily internalize costs of air pollution

• Future Work

Human requirements9,700 (l) air / 24 hours

• Take a few breaths

• Average human per 24 hour needs

0.5 (l)/breath x 13.5 breaths/min x 60 min/hr x 24 hrs/day

= 9,700 (l) clean air / day

• Define: 1 human-day (hum-day) 9,700 (l)– 40 hum-day of air => 40 x 9,700 litres

• Define 1 pop-day = N people in population x 1 human-day– Montreal: 1,812,723 people x 9,700 (l)/person) = 1.76E+10 (l). – 100 pop-day air => 100 times the volume for Montreal population

Engines as consumers of air

• Do you know how much air (litres) goes through our combustion engines?

• Litres of air through engine cylinders =>Cylinder displacement (litres) x rpm x minutes

• For 4-stroke engines => rpm/2– cylinders cleared every 2nd cycle

2-stroke engineslitres air = Displacement x rpm x minutes

Engine Cylinder rpm Operating litres air Hum-dayType Displacement time (min) consumed/ of air

(l) session

lawn mower .05 5000 30 7500 0.8 / 30 minhedger .02 5000 30 3000 0.3 / 30 minchainsaw .04 5000 30 6000 0.6 / 30 minJet ski 1.1 4000 30 132000 14.0 / 30 min

(not diluted with ambient air)

The path of air through a 4-stroke engine

Cylinder empties every 2nd revolution

Volume = Displacement (l)x rpm/2 x minutes

Assumptions for engines

• air through cylinders becomes tainted• air passing through engines not used again by

same engine or any other engines

• direct exhaust unhealthy for human consumption– Here exhaust not diluted with more ambient air– How much would you dilute exhaust before breathing

it? 3X? 10X? 100X? • No dilution approach underestimates volume of

air impacted by combustion engine processes

Variety of engine sizes considered(Source “The Gazette, Driving section)

Engine cylinder displacement comparisons used in this model(Note: data in litres unless labelled cc/10, multiply cc/10 data by 10 to convert into actual cc)

2.0

4.0

5.0

1.10.6 0.8

3.0 3.1

4.34.7

6.06.6

10.010.5

12.0 12.0 12.0

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

1Various engines (see legend on right)

Engi

ne d

ispl

acem

ents

(l) o

r cc

2 stroke hedge trim cc/102 stroke chainsaw cc/102 stroke lawn mower cc/10Jet ski engines (l)Smart car (l)Mini fuel efficient cars (l)Formula 1 (l) (18,500 rpm)Compact car (l)Average SUV (l)Luxury car (l)4WD Loaders (l)Avg School BusCity BusExcavators (l)Dump Truck (l)Cement truck (l)Hauling Rig (l)

4-stroke engines(l) = Displacement x rpm /2 x minutes

Engine Cylinder rpm Operating litres air Hum-dayDisplacement time (min) /session of air

CitySmart car 0.6 3000 60 72000 7 / hrCompact car 3.1 3000 60 280000 29 / hrSUV 4.3 3000 60 390000 40 / hrSchool bus 6.6 3000 60 550000 41 / hrTruck 12.0 3000 60 1100000 110 / hrConstr. Truck 12.0 3000 60 1100000 110 / hr

HighwayCompact car 3.1 2500 45 170000 18 / 45min

SUV 4.3 2500 45 240000 25 / 45min

Trucks 12.0 2500 45 670000 70 / 45min

Formula 1 3.0 18500 60 1620000 167 / hr

(not diluted with ambient air)

Air flow through airplane engine

• Airbus A320 representative for Trudeau Airport • Estimated 250 take-offs & 250 landings / day

(Isaac, 2005).• Take-off speed, landing speed, throttle settings

from http://www.flybernhard.de & personal communication with commercial pilot.

• Estimates of airflow using NASA engine simulator website

• Volumes verified with owner engine simulator website (Benson, Thomas, 2005).

http://www.grc.nasa.gov/WWW/K-12/airplane/ngnsim.html

Air consumption data for one Airbus A320 CFM56-5A1 engine

Process Throttle Speed Core Rate Minutes Air Vol Hum-day(%) km/h Airflow (l)/s litres (/2 engines)

kg/sT-Off –Terminal 40 0 .009 7.0E+00 30 1.5E+07T-Off – Taxiing 55 10 22.53 1.8E+04 5 5.3E+06T-Off 90 285 34.2 2.7E+04 1 1.6E+06 => 4.5E03

Landing 60 217 34 2.6E+04 15 3.2E+06Landing – Taxiing 55 10 22.53 1.8E+04 5 5.3E+06Landing-Terminal 40 0 .009 7.0E+00 15 7.6+E06 => 3.3E03

------- -------------Total: 3.8E+07 (l) 7.8E03

(not diluted)

Overview of engine air consumptionCategory Consumption Units w.r.t. Total Total daily # pop-day

air litres 1 human number consumption of air(1)/9700 in city /category (l)

Humans 9.7E+03 (l)/day 1.0E+00 1812723 1.76E+10 1.0

2-stroke 1 mower 7.5E+03 (l)/0.5 hr 7.7E-01 443947 3.3E+09 0.21 hedger 3.0E+03 (l)/0.5 hr 3.1E-01 443947 1.3E+09 0.11 chainsaw 6.0E+03 (l)/0.5 hr 6.2E-01 88789 5.3E+08 .031 Jet ski 1.3E+05 (l)/0.5 hr 1.4E+01 1421 1.9E+08 .01

4-stroke Local vehiclesEfficient 7.2E+04 (l)/hour 7.4E+00 1776 1.3E+08 0Compact 2.8E+05 (l)/hour 2.9E+01 1065473 3.0E+11 17SUV 3.9E+05 (l)/hour 4.0E+01 710315 2.7E+11 16School bus 5.5E+05 (l)/hour 4.1E+01 500 1.2E+09 0.1Truck 1.1E+06 (l)/hour 1.1E+02 266368 2.3E+12 133Const. 1.1E+06 (l)/hour 1.1E+02 10000 8.6E+10 5

Highway vehiclesCompact 1.7E+05 (l)/.75 hr 1.8E+01 100000 1.7E+10 1SUV 2.4E+05 (l)/.75 hr 2.5E+01 90000 2.2E+10 1.2Truck 6.7E+05 (l)/.75 hr 7.0E+01 70000 4.7E+10 2.7

A320 Airplane - two A320 CFM56-5A1 enginesTake-off 4.4E+07 (l) 4.6E+03 250 1.1E+10 .64Landing 3.2E+07 (l) 3.4E+03 250 8.0E+09 .47

----------- ----------Total: 3.1E+12 (l) 178 pop-days of air

Number of human-days worth of air /engine /basic operating time. 1 human-day of air = 9700 litres / Note multiply airplane volumes by 10

1 1 0.3 1 3 0 729

40

111

18 25

69

111

51

455

331

0

50

100

150

200

250

300

350

400

450

500

1

Process

num

ber

of h

-d o

f air

/uni

t / o

pera

ting

time.

1 human1 2-stroke mower1 2-stroke hedger1 2-stroke chainsaw1 2-stroke Jetski1 electric car1 super efficient car1 local compact Car1 local SUV1 local Truck1 highway compact Car1 highway SUV1 highway Truck1 local construc. Truck/hr1 local School bus1 A320 plane take-off /101 A320 plane landing / 10

x10

x10

Airbus A320

Vehicles

Individual Engine Consumption Comparison

Single Units consumption Summary

• Airplane consumes largest volumes air / unit – [Take-Off + Landing] = requires at least 8,000 hum-day of air– large portion used at terminal or during taxiing

• Local truck, incl. construction truck, consumed large volumes – approximately 110 hum-day of air / hour

• Highway truck consumes approximately 70 hum-day / 45 minutes

• Local school bus, SUV, compact car use – 51, 40 29 hum-day air / hour

• 2-stroke engine• jet ski, lawn mower, chainsaw and hedger• 7.8 1.6 1.2 0.6 hum-day air / hour

Using reference numbers for island of MontrealCould plug model into city databases?

Category Consumption Units w.r.t. Total Total daily # pop.-dayOf air 1 human number consumption of air

(l) (1)/9700 in city /category (l)

Humans 9.7E+03 (l)/day 1.0E+00 1812723 1.76E+10 1.0

2-stroke 1 mower 7.5E+03 (l)/0.5 hr 7.7E-01 443947 3.3E+09 0.21 hedger 3.0E+03 (l)/0.5 hr 3.1E-01 443947 1.3E+09 0.11 chainsaw 6.0E+03 (l)/0.5 hr 6.2E-01 88789 5.3E+08 0.031 Jet ski 1.3E+05 (l)/0.5 hr 14E+00 1421 1.9E+08 0.01

4-stroke –Local Efficient 7.2E+04 (l)/hour 7.4E+00 1776 1.3E+08 0Compact 2.8E+05 (l)/hour 2.9E+01 1065473 3.0E+11 17SUV 3.9E+05 (l)/hour 4.0E+01 710315 2.7E+11 16School bus 5.5E+05 (l)/hour 4.1E+01 500 1.2E+09 0.1Truck 1.1E+06 (l)/hour 1.1E+02 266368 2.3E+12 133ConstructionTrucks 1.1E+06 (l)/hour 1.1E+02 10000 8.6E+10 5

4-stroke HighwayCompact 1.7E+05 (l)/.75 hr 1.8E+01 100000 1.7E+10 1SUV 2.4E+05 (l)/.75 hr 2.5E+01 90000 2.2E+10 1.2Truck 6.7E+05 (l)/.75 hr 7.0E+01 70000 4.7E+10 2.7

A320 Airplane - two A320 CFM56-5A1 Take-off 4.4E+07 (l) 4.6E+03 250 1.1E+10 0.64Landing 3.2E+07 (l) 3.4E+03 250 8.0E+09 0.47

---------- ------Total: 3.1E+12 (l) 178 pop-days of air

(1) X (2) = (3)

1 highway SUV9.E+0490000SUVs going through/day

1 highway compact Car1.E+05100000Cars going through/day

1 local Truck3.E+0515% with a TRUCK for # trucks

1 local SUV7.E+0540% with an SUV for # SUV

1 local compact Car1.E+0660% with a car for # cars

1 super efficient Car2.E+030.1% pop with super efficient cars

1 Electric car9.E+010.005% pop with electric cars

1 2-stroke Jetski1.45018E+030.08% pos with Jet skis

1 2-stroke chainsaw9.06362E+045% pop with gas chainsaws

1 2-stroke hedger4.53181E+0525% pop with gas hedgers

1 2-stroke mower4.53181E+0525% pop gas lawn mower

1 human2.E+061,812,723Number of residents

CONSUMERS0.E+000CONSUMERS

1 lawn air production5.E+0530% population with lawns

1 tree air production2.E+05

1 scat ha6.E+041.5% of total coverage from scat ha

1 dense ha7.E+041.0% of total coverage from dense ha

1 very dense ha5.E+040.5% of total coverage very dense ha

Process3Total percentage greenspace

ProducersPRODUCERS

Actual numbers per categoryNUMBERSCATEGORIES Spreadsheet model used for calculations

Consumption of air per category as number of population-days of air1 population-day of air = air required by population of the urban airea

1.0 0.3 0.0 0.0

17.1

1.0

15.9

1.2

138.3

2.7 0.6 0.50.0

20.0

40.0

60.0

80.0

100.0

120.0

140.0

1

Category

Num

ber o

f pop

ulat

ion

days

of a

ir All peopleAll small enginesAll electric carsAll super efficient carsAll local carsAll highway carsAll local SUVsAll highway SUVSAll local TrucksAll highway TrucksAll planes Take OffAll planes Landing

Local cars and SUVs

Local Trucks

Using estimates of numbers of engines in MontrealConsumption expressed as # pop-days of air / day

Air consumption Montreal islandEngines use 180 pop-day of air / day

• Local & highway trucks => 141 pop-days of air / day (78 % of total)

• All vehicles (not trucks): 35 pop-day of air / day ( 18% of total)

• All airplane engines: 1.1 pop-day of air / day

• All 2-stroke engines: approx. 0.3 pop-day of air / day

• Suggestion for strategy in poor air quality episodes– Focus on big polluters (trucks) could help prevent more air pollution

– Ex: Pierrefonds idling bylaw• lower fines for idling business trucks than for vehicles when left idling

Percantage of total air consumed by engines/day by each categoryAll engines combined consume approx 180 times the air required by the urban population/day

0.6 0.2 0.0 0.0

9.7

0.6

9.0

0.7

78.1

1.5 0.4 0.30.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

1

Category

% o

f tot

al a

ir c

onsu

med

All peopleAll small enginesAll electric carsAll super efficient carsAll local carsAll highway carsAll local SUVsAll highway SUVSAll local TrucksAll highway TrucksAll planes Take OffAll planes Landing

Local Trucks

Local cars and SUVs

A stagnant High pressure scenario air consumption inside “box”

• Under a stagnant ridge (no mixing) - how quickly is stagnant air consumed by engines?

• (1) Reference supply of stagnant air (box) over region - Montreal– boundary layer 0.3 km over 500 km2 area (island) => (500 x 0.3) km3, or 1.5E+14 litres.

•• (2) Sum of all air volumes consumed by all engines in 1 day

– 3.1E+12 litres of air/day for all engines

• (1) / (2) => 48 days (in this scenario with no dilution) – for urban engines to consume at least once total local air in this “box”– Likely much shorter times if we dilute exhaust to make it breathable– If each litre exhaust diluted with 10 other litres only 5 days to full consumption/dilution

• “The # of days to total local air consumption” of interest: – Offers governments and public a practical rationale for encouraging (discouraging) local

behaviours that clean (pollute) the stagnant air supply– When a batch of stagnant air arrives, manage activities to avoid/delay using air in box

Validating air consumption volumes• Government lab data could validate engine air volume consumption data.

• Determine, for each litre of air sent through engines – which proportion is contaminated air. – Then, convert number vehicles from traffic cameras into real- time estimates of tainted air (l)

• Applied to highway vehicles– # Vehicles x Engine Displacement x rpm/2 x Commute Time x %Tainted = Litres tainted air

• where – Vehicles = Number of vehicles (N) from traffic cameras– Displ. = Average engine displacement (litres) per engine– rpm = Average rpm for highway vehicle– Commute Time = Average commuting time (minutes)– %Tainted = Percentage of exhaust considered to be tainted (lab data)– Litres = litres of air consumed/tainted by (N) vehicles during commute time

• Could we us real time estimates of vehicle exhaust volumes?– To complement pollutant inventories databases? – To generate a persistence dataset of tainted air volumes?– To help model vehicle exhaust plumes created near busy streets or highways

Part 2: Education

• Education– A new approach to communicate air quality

information• Package impact of our actions in terms humans

can relate to• Allows new types of public education tools

Air volume consumptionNew public education tools

• Growing interest in air pollution information in terms the public can better relate to

• Educating public increases likelihood of public participating in changing polluting behaviors to less or non-polluting ones (DeCicco, J. et al., 1990)

• Public education often preferred option of many levels of government

• Could our air quality education packages be more effective?

From the One tonne challenge to…Your air consumption footprint

• web sites used to help citizens calculate their production of CO2

• Similarly, the public could calculate air volume footprints, (how much air they use)

• City-wide air volume consumption “footprints” also possible

• Encourages public awareness of impact of urban activities on air

Personal Input Parameters used in Air Consumption Footprint Calculation

50

4 4

90

6

30

20 20

00

10

20

30

40

50

60

70

80

90

100

Activity

Inpu

t Val

ue (S

ee L

egen

d on

Rig

ht)

Area of your lawn (m2)Number of people at homeYour car engine's displacement in litres (l)Your minutes of driving/day (min)Number of days driving/weekDisplacement of 2-stroke mower (cc)Displacement of 2-stroke hedger (cc)Displacement of 2-stroke blower (cc)Displacement of 2-stroke chainsaw (cc)

Sample input parameters for air volume “footprint”

Air Volume Consumption Footprint in units of human-days of air / category / day1 human-day (h-d) = 9,700 litres / Negative values signify consumption of air

Ex: 20 h-d means that activity uses the volume of air 20 people would breathe in 1 day

2 1

-4-1

-46 -48

-60

-50

-40

-30

-20

-10

0

10

Activity (see legend)

Air

volu

me

cons

umpt

ion

as n

umbe

r of h

-d o

f air

Trees air production as # h-d of airLawn air production as # h-d of airTotal breathing volume as # h-d of airLawn care air consumption as # h-d airDriving air consumption as # h-d of airNet air consumption as # h-d of air

Value of air consumption footprint• Awareness of air consumption footprint

– Identifies High/Low volume air consumption activities– In smog episodes, ban High consumption activities– Easier and more personal to rationalize change

• Not use the SUV to avoid polluting the air for 40+ people

• Easier to set sustainable air volume consumption/reduction targets

• Helps gov. and citizens participate in clean air pro-active management

More informative dashboardsMaking better use of tachometers

65

54

43

11

3222

76

Display of Hum-days of air for 3.5 (l) engineex: 1 hour @ 2,500 rpm => uses 22 hum-days of air

65

54

43

11

3222

76

Part 3: Economic Transactions

• Economic implications– An atmospheric tragedy of the commons– Proposal for a clean air trading system– Marketplace could then internalize costs of air

pollution

Tragedy of the “Unregulated” Commons

• Popular economic theory• Shared resource becomes overburdened as

each person uses more & more of the resource for individual gain.

• Eventually, the resource dwindles or is wiped out, resulting in lower gains for everyone. Example: over fishing, forestry, air pollution.

• Failure to regulate the use of resource results in a dwindling resource

• In this case more air pollution

• ( http://www.thesystemsthinker.com/tstglossary.html )

Atmospheric Tragedy of the Commons?

• Citizens use air in daily lifestyles – No full accounting for impacts on air quality

• Accounting for impacts on the air – would allow marketplace to better manage resource

• It’s not easy but…• Could we find way to measure our use of air?• Could we clearly describe impacts of actions on air? • “Internalize” costs of air pollution to avoid atmospheric “Tragedy of

the Commons”

• We can only internalize costs if we can measure air consumption/impacts in a user-friendly manner

• Air Volume consumption approach?

Economic precedents?• Taxation/pricing tools used regularly to promote conservation• Industry likes economic solutions rather than government

regulations

• Internationally, CO2 reduction achieved when – industries/countries that produce too much CO2 – pay a $fee$ to industries/countries that produce less CO2

• Municipally: water meters encourage water conservation– Note: water meters measure volume of water, not pollutants in water

• Municipally: $Fee$ when residents have > 2 bags garbage/week

• Empty bottle refunds encourage management/returns of bottles

Why notA local clean air trading system?

• Volumetric approach to use of air allows simple computation of air volumes used by individuals, groups, cities, other groups?

• Could relate air used as function of litres of gasoline purchased?– 10 (l) / 100 km => 22,500+ (l) air impacted / (l) of gasoline– Cost of air should/could be included in cost of gasoline

• What if each entity (Citizen? City? Country?) were assigned N litres of clean air for a period of time– If more than N litres of air required,

• then pay additional pre determined “polluting” fee,• or barter or buy permits from others whose activities don’t consume as much

air.

Clean Air Trading Fund ?For those who need to sell/buy clean air

Think locally…Act globallyA global clean air trading system?

• Like CO2, apply clean air trading internationally?

• Developed countries (large number of engines) pay $fee$ to developing countries (with fewer engines) for permission to pollute the air with engines

• Provides incentives for polluting countries to reduce their pollution

• Rewards developing countries for development not based on combustion engine

• A more equitable manner to share the atmosphere• Third world assistance built into the marketplace

Conclusions• Need to better understand how daily activities impact

local air• Ventilation-based accounting of air used in engines

could help– Humans need 9,700 (l) of clean air / day – Estimates for air consumption for various engines presented

• Locally, truck engines identified as group using most air– / day , they use 140+ times volume air required population of

Montréal.– Total number of engines consume 180 pop-day of air /day

Conclusions …cont’d• New education tools from ventilation approach

– Info in terms of human consumption easy to relate to– A web interface for air consumption footprint calc – Better tachometer displays for cars– Governments could have clearer air quality baseline and targets

• Economic system to account for cost of air– Volumetric approach makes possible to connect cost air– Cost of air should be included in costs of fuel– Local clean air trading system could encourage pollution

prevention– Could work both locally and globally to promote clean styles of

development.

Future Work• Expand list of consumers of air in urban areas

– Public transit, furnaces, wood stoves• Expand impact on each litre through engine = [fumes+smog+PM]• Connect to municipal databases for real time numbers• Perform “what if” scenarios to assist in policy development, lifestyle

impact evaluations

• Create more useful public awareness air quality forecasts to facilitate bahaviour changes

• Add activities that clean the air (vegetative processes) to then create a net balance of air consumption

• CMOS 2005 poster:• http://chebucto.ca/Science/AIMET/lewis/air_model

How much air will you use today?

Fin - Merci

Calculating Production + Consumption

• Producers/Cleaners• 1 leaf produces 5 ml O2 / hour. Use this data to estimate O2

production from a tree • 1 average tree, crown = 6.1 m => N leaves * 5mlO2/leaf/hr * 8

hours*1(l) air/.21(l)O2 • 1 lawn: 58m2 lawn => air for 1 human/day

• Engines• 1 (l) 4-stroke=volume cylinder *(rpm/2)*60 min, 1 (l) 2-stroke= vol

cyl *rpm*60 min• 1 Airbus A320

engine:http://www.grc.nasa.gov/WWW/K12/airplane/ngnsim.htm• 1 pesticide, gas station, paint shop => W x D x H (m3) => litres of

air impacted / day