Air Quality — 10 August 2014

Here at Southern Pacific Review we are exploring what steps other cities are doing to the reduce air pollution that comes from mass transit, so that we might do the same here in Santiago, a city that is heavily polluted by smog in the winter, 44% of which comes from vehicles (6% of that from city buses). Today we look at what Bogotá, Colombia has done to start to address its pollution problems.

Some Useful Links
Santiago Air Android App
Sources of Air Pollution in Santiago
Copper Smelters in Chile
Air Pollution in Santiago
Santiago Air Quality
Transantiago Contribution to Pollution
Electric Buses in Bogota

Bogotá is moving towards the final stages of its transition to a Transantiago-type system for public transport. This is where the city makes direct payments to the bus companies that provide transportation for the city instead of having private operators operate outside some overriding agency. Santiago has already completed that transition to one management system, called Transantiago.

In Bogotá today you can see many private buses that are not part of the Transmilenio system. Most of these are older vehicles that do not come anywhere close to the Euro V emission standards, which is the current emission standard there. A Volvo manager we talked to there said that most of those older buses are Euro 0 emissions standards, which has no limits at all on the particulate matter (PM) pollution.

The situation in Santiago is not much better. In Santiago, the fleet of 6,500 buses is operating under the Euro III standard, which is 14 years old. That allows 5 times the particulate matter pollution as the Euro V Bogotá standard. The current vehicle emission standard in Europe for heavy vehicles is Euro VI, which is 10 times cleaner than Euro III. The emission standards in Chile will probably change in 2016 when the government completes the new plan to reduce pollution in the city.

Particulate matter (PM) pollution is the main problem in Bogotá. In Bogotá, PM is responsible for more than 5,000 deaths annually, while in Santiago it kills more than 4,000 per year. This pollution is what produces that brown haze that hangs above the city in winter, sending many children, elderly people, and people with respiratory problems to the hospital.

Bogotá and Santiago both recognize this crisis and are taking steps to address the problem. But they cannot get rid of all the dirty vehicles overnight without addressing the needs of business, who have employees to pay and need to operate at a profit.

In order to move to cleaner and alternate fuel vehicles, the transit operators need to be shown solid figures that the payments they receive from the city are going to yield the same profits and that buying the newer vehicles is not cost prohibitive. Any changes that drive up costs would drive up passenger fares, which is politically problematic anywhere, especially in developing nations.

But Bogotá has provided those hard numbers.  Last year they completed a side-by-side comparison of alternate fuel and diesel buses. The study was funded by the Inter American Development Bank (IDB) and the Clinton Climate Initiative.

Alternative Fuel Buses in Bogotá

The city of Bogotá has already taken delivery of 231 hybrid diesel-electric hybrid buses from Volvo and is buying 790 more. (We will explain what Volvo has done in another article.) But the city has also decided to use zero emissions all-electric vehicles and is taking delivery of 40 of those from the Chinese company BYD. The first order is for 40, 12-meter, 60-passenger vehicles. The next order will include the 18 meter, articulated buses, or those larger buses that have a flexible section in the middle.

BYD builds electric buses and other vehicles in Brazil (and elsewhere in the world) and is building a new factory there to manufacture more electric vehicles and iron phosphate batteries. It is the iron phosphate battery, that BYD invented, that makes it possible to use electric vehicles for public transit. The iron phosphate battery allows a bus to run 270-280 km on one charge of 4 to 5 hours, a longer range than lithium batteries. That range is sufficient to meet an 18 hour working day for the vehicle.

In a press release, BYD Motor’s President Stella Li stated, “We are the only electric bus than can run all day in city routes without being charged, unlike other electric bus competitors.”

The Clinton Initiative

The goal of the IDB-Clinton study was to look at the cost of operating each type of vehicle to see if it made financial sense for the city, with the goal of reducing vehicle emissions. The report concluded that “the profitability of the hybrid and electric vehicles are competitive with the diesel vehicles.”

The IDB study ran diesel, diesel-electric hybrid, and all-electric vehicles side-by-side along the same routes to see what would be the operating and acquisition costs and the payback period for each type of vehicle. (Payback period means the time in which the operator has recovered the purchase price through payments from Transmilenio, and in the case of the alternate fuel vehicles, that plus savings in fuel and maintenance.) The alternate fuel vehicles cost more to purchase, but their operating costs are substantially less than diesel, plus they meet the goal of reducing air pollution, which is the whole point of the program.

The IDB study did not say anything regarding the environmental impact of switching from diesel to alternative fuel vehicles, as that was not in the scope of the study. (We will look at the details of that in other articles, as we continue to write on this theme.) But it does not take a detailed analysis to realize what is obvious, which is that all-electric vehicles emits no pollution and hybrid vehicles emit less emissions than vehicles that run purely on diesel fuel. Anyone who has sat behind an old diesel bus belching smoke in traffic can understand that.

Operating Costs and Capital Expense

Electric buses cost significantly more than diesel buses. But given the cost of fuel and the lower maintenance costs, the capital outlay added to the operating expenses are basically the same as diesel buses over 12 years. That is the amount of time that diesel buses are required to last under most developed-nation transit system rules, although the BYD bus is built to last for 20 years. Transit operators typically run their diesel vehicles from 12 to 18 years.

The main reason electric buses cost more is the high cost of the battery. (For anyone who has ever purchases a Toyota Prius gasoline-electric hybrid, Chevrolet Volt electric, or Telsa luxury electric vehicle they already understand that.) So BYD lets its customers rent the battery instead of buying it, to drive down the expense. The battery can be purchased outright for $227,325 or rented for $2,555 per month. These are figures that were used for the IDB study.

Here are the bus prices for a 12 meter 60 passenger bus as of March 2013 given in US dollars.

diesel: $221,745
electric w/o battery: $314,551
electric w/ battery: $541,867

The All Electric Vehicle

BYD already has buses operating in New York, Miami, Los Angeles, different cities in Europe and, of course, China, where air pollution is much worse even than in Latin American. Their introduction to South America is new.

In the Bogotá pilot project, the electric buses were shown to be the most fuel efficient on a liter of fuel per kilometer basis. (In other words, to have an apples-v-apples comparison it is necessary to convert the two types of fuel to some common scale, which is energy output in terms of BTUs [British Thermal Units] or some other measurement of energy. For example, in the USA, analysts use the term GGE [gasoline gallon equivalent] when looking at the efficiency of natural gas automobiles versus those that run on gasoline.)

In Bogotá, the electric buses were shown to travel 1.13 km per kWh (kilowatt hour of electricity). On a liter equivalent basis, this translates to 0.14 L / km in terms of cost and 0.09 L / km in terms of energy output. In other words, the first number is based upon the prices of electricity and diesel fuel at the time of the study and the second is based upon the energy output of each type of fuel. The IDB said the overall fuel savings is 58% with the electric vehicles.

To put that into perspective, using the costs figures at that time, an electric bus operating a route of 250 km per day would burn the equivalent of 35 liters of diesel fuel while a diesel vehicles would burn 55 liters.

In a telephone interview,Micheal Austin, Vice President of BYD American, and Lara Zhang, Colombia Country Manager for BYD, talked about the BYD buses and the Bogotá project.

Micheal said that the “savings is about 70% in operating expensive.” He said, “Every 5 weeks you have to change oil and oil filters” on a diesel bus. “Every 400,000 miles (640,000 KM) you have to rebuild the transmission and drive train. There is no transmission on electric buses.”

The other cost savings is the electric buses have no engine to rebuild. The power is in the wheel hub themselves.

Micheal says that, “You need to rebuild engines about every 250k – 350k miles” which at most could be stretched to 400 or 500 k. The diesel buses are designed to last 12 years. The BYD electric is built to 20 years.  The IDB study used the same 12 year figure in their calculation of the payback period. Michael says that transit fleets in actual practice usually run their vehicles from 12 to 18 years before replacing them.

The IDB study says that the maintenance costs are 51% less with electric than diesel buses.

As an added plus, the electric buses are quieter too.  Noise is a problem in urban areas. When idling, the buses make no noise at all. Plus because they have no drive train hanging underneath, so they are easier to board for older people, as the buses ride low-to-the-ground.

Lara summed up the BYD experience, “BYD was thrilled by the vision of Bogotá Mayor Gustavo Petro when he initiated low-carbon and sustainable transportation at the 9 major bus operators in Bogotá. BYD was one of the first to offer electric buses for testing. Our zero-emissions, 12-meter bus was tested by Transmilenio successfully in 2013 — the results of the tests proved BYD’s eBus was cleaner, quieter and saved more money that any other bus operating in Latin America.

“The BYD eBus is homologated for Latin America and ready to enter Transmilenio SITP systems — BYD Colombia is working on a project of 40 electric bus for launch in Bogotá in 2015. Additionally BYD will bring the first battery-powered 18-meter articulated electric bus to Bogotá starting Jan of 2015.”

So the use of electric vehicles in Bogotá and the demonstrated cost savings bodes well for the debate currently underway in Chile with the new Bachelet government on how to reduce vehicles emissions and do so in a cost-effective manner.

As we said we will be looking at all types of alternate fuel vehicles here at Southern Pacific Review include the Euro VI diesel vehicles, which some studies show can be cleaner than natural gas vehicles.  As you probably know, natural gas buses are widely used in cities like Washington, D.C. as a means of reducing pollution.  Chile has just secured a long-term of supply of natural gas from the newly-built Sabine Pass LNG export facility in Louisiana.  Liquid natural gas (LNG) is used in heavy vehicles in the USA by such companies as the UPS package delivery company.  There are many alternatives available to make the bus fleet as well as automobiles, heavy vehicles, and delivery vans run cleaner in Santiago in order to reduce the dire pollution problem here:  Euro VI diesel, natural gas, liquid natural gas, gasoline-electric hybrid, diesel-electric hybrid, and all electric.

Suggested Reading

Special Report: Pro-business Energy Reform to Improve Air Quality in Chile


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