Costs and Emissions Appraisal Tool for Transit Buses

The Excel-based Tool presented here provides a flexible, transparent platform that can quickly calculate the annual financial costs and emissions incurred by two different bus fleets. The model is particularly useful for agencies and operators in developing countries during the initial project scoping phase. It can help them shortlist alternatives and determine which of them deserves detailed analysis

The main goal of this tool is to allow decision-makers to compare the cost and emissions reductions of two bus fleets, each composed of up to three bus types. In this tool, bus types can differ in terms of fuel type used, the technology used to achieve different emissions standards, and length. The users have to input fuel and vehicle unit cost data for a city or country. Based on either the inputted or default data, the Tool calculates the costs and emissions of each bus type and the total costs and emissions for each fleet.

The three main benefits of this tool are:

• Flexibility. Users can create their own fleets, including and excluding different bus types to reveal how individual buses affect fleet costs and emissions.
• Comparativity. Users can use the Tool to see which fleet performs best (or reduces costs and emissions more).
• Ability to be used by agencies that lack data. Users can use local data (the preferred approach) or draw on the default cost and emissions tables (a good option for users that lack local data).

Even though the tool can help in the decision making process, one must not forget about some limitations when using it. For instance, the tool distributes capital costs across years, does not capture full life cycle of emissions or automatically optimize options. Finally, the Tool assumes constant (rather than declining) fuel economy over the life of the vehicle and the default data provided may not reflect local conditions.