FACTSHEET
Lagos CO2 Emissions Assessment Handbook
Developer
Integrated Transport Planning Ltd for World Bank/Lagos Metropolitan Area Transport
Authority
Location
This handbook provides guidance to calculate the impact on carbon emissions from the
implementation of a new transport scheme, including the collection of the necessary data
required for this task. The objective of the manual is to set out the monitoring and
evaluation framework for the estimation of carbon emissions savings through the
implementation of new BRT lines in Lagos.
This methodology gives practical instructions on the collection of the data required for the
calculation of emissions estimates, including specifications for each of the different surveys
required, advice on choice of survey location and a schedule for survey timings.
Methodology
The aim of this methodology is to quantify the true emissions reductions realized by
delivery of the Bus Rapid Transit system in a robust way, allowing confident assertions to
be made about the real success of the scheme in reducing greenhouse gas emissions. The
following emissions sources are included within the estimates:



Vehicle emissions produced by the BRT system
Changes in vehicle emissions for other vehicles within the study area caused by:
o Changes in vehicle distance (activity)
o Changes in vehicle speed/driving conditions
Rebound effect – encouragement to travel through improved travel conditions
There are many factors which impact on emissions which are not directly related to the
introduction of the BRT system. There may also be indirect changes in emissions as a result
of the BRT system occurring outside the study area which cannot easily be captured. The
following factors are not included within the estimates:


Changes in vehicle activity beyond the study area
Electricity usage within BRT system (eg stop lighting etc)
With regard to geographic boundary, it is important to consider that the spatial area of the
project is the entire zone in which the project operates. This is the entire area bounded by
the trip origins and trip destinations.
The process of calculating emissions savings derived from the BRT project can be
summarized in the following steps:
Baseline Scenario
Baseline emissions (termed “Counterfactual in the Handbook) are the emissions which
would have been caused by the project passengers in absence of the project activity. This is
the hypothetical situation in which BRT is not implemented. The emissions calculations are
calculated as the difference between observed emissions with the BRT scheme in place and
the baseline. In order to quantify vehicle emissions in the base year and baseline scenario,
vehicle kilometers traveled, number of passenger trips and vehicle occupancy can be used.
Then, baseline emissions can be estimated based on following method:


In the short-term post-implementation, the base year scenario as recorded in
“before‟ surveys is likely to provide a good proxy for the baseline. These surveys
will have been carried out for the study area and are therefore directly comparable
to the “after‟ surveys carried out on the same corridor. Up to 3 years post
implementation, the baseline scenario will be taken as being equivalent to base year
conditions before BRT implementation.
Over time, the base year scenario will become increasingly less robust as a proxy for
baseline (without the BRT) conditions due to exogenous changes in city geography
and demographics, transport network, policy and travel demand. From year 4
onwards, the baseline is estimated based on surveyed trends recorded on a control
corridor.
In order to determine the base year scenario, the following surveys are carried out:

Classified Traffic Counts and Occupancy Counts: The objective of this survey is to
record the number of vehicles travelling along the BRT corridor(s), and to record
the occupancy of vehicles to allow passenger flows to be determines.

Origin Destination/Roadside Interview Surveys: The objective of these surveys
is to collect information about travel patterns which will underpin the estimation of
average journey distances to populate the vehicle activity calculation. The survey
must collect information on journey distances for travelers on each of the public
transport bin types, for taxi passengers and for travelers using private cars. Heavy
goods vehicles (trucks) are assumed to have fixed journey distances, and are not
included in the origin-destination surveys.

Drive Cycle Surveys: The aim of the drive cycle surveys is to collect information on
typical driving patterns in the city for use in the vehicle energy intensity
calculations. The survey is designed to capture average driving conditions across the
different vehicle bin types within the study area, and to monitor how travel
conditions evolve over time following the introduction of the BRT scheme.

Fuel Consumption Surveys: This survey establishes the fuel consumption of the
types of vehicles using the highway network, under the driving conditions that are
typically experienced within the city. By understanding the amount of fuel
consumed by each vehicle “bin‟ under different driving conditions, the relationship
between fuel consumption and CO2 emissions can be used to calculate the CO2
emissions for the individual vehicle and by extension, in conjunction with the other
survey data, for all vehicles activity.
Project Emissions
In order to estimate project emissions, the monitoring of the BRT corridor will continue
through the life of the project, with comparative surveys undertaken at regular intervals.
These surveys will provide a direct comparison back to travel conditions in the base year
(before the scheme). In order to quantify vehicle emissions in the project scenario, vehicle
kilometers traveled, number of passenger trips and vehicle occupancy can be used.
Inputs
Input and monitored data collected by surveys regarding to vehicle types as follows:
Vehicle
Types
Car
Taxi
Classified
Traffic
Counts
Occupancy
Counts
Subclassification
Origin
Destination
/Roadside
Interview
Surveys
Drive Cycle Surveys
Method
Fuel
Consumption
Surveys
Subclassification
Petrol/diesel
Journey
distances for
travelers
Car survey vehicles to
travel along pre-selected
routes within hourly
intervals
Engine size,
Petrol/diesel
Petrol/diesel
Journey
distances for
travelers
Volunteer taxi vehicles to
be given GPS devises,
Engine size,
and to then operate as
Petrol/diesel
normal, taking fare
paying passengers
Truck
Light goods,
medium
goods, heavy
goods
Motorcycle
/Okada
2-stroke/4stroke
Heavy goods
vehicles
(trucks) are
assumed to
have fixed
journey
distances,
and are not
included in
the origindestination
surveys.
No of Axels
Volunteer Okada to carry
GPS equipment and
operate as usual
2-stroke/4stroke
"Mystery traveler"
surveyors to carry GPS
equipment in bags and to Engine size
travel on selected bus
routes.
Danfo 14
seat
Danfo 18
seat
Danfo 22
seat
Molue
Coaster
Other Large
Bus (eg
Lagbus)
Volunteer light and
medium goods vehicles
from local businesses to
be selected to carry the
GPS equipment and
operate as usual. Heavy
goods vehicles to be
"tailed" by survey cars
(as these vehicles are
more likely to operate
long haul routes beyond
the study area.
Engine size
Journey
distances for
travelers
“Mystery traveler”
Engine size
surveyors to carry GPS
equipment in bags and to Engine size
travel on selected bus
Engine size
routes.
Vehicle type
BRT Trunk
Line Bus
“Mystery traveler"
surveyors to carry GPS
Vehicle type
equipment in bags and to
travel on BRT route.
BRT Feeder
Bus
"Mystery traveler"
surveyors to carry GPS
equipment in bags and to Vehicle type
travel on BRT feeder
route.
Pollutants/Gases Analyzed
CO2
Evaluation
No independent evaluation has been undertaken of this methodology. However, the
following strengths and weaknesses apply.
Strengths
This methodology describes
estimating accurately the emission
reduction of new BRT lines
implementation.
Weaknesses
The data collection requirements
could be costly.
Clearly laid out methodology and data
collection instructions.
Guidelines for data collection and a
clear procedure make this
methodology more accurate than
some method available whilst being
less onerous than following a CDM
methodology.
Data collection techniques could be
used for other tools and
methodologies.
References
Integrated Transport Planning Ltd, 2010, Lagos CO2 Emissions Assessment Handbook, Final
Edition