[tsk1979]

Originally Posted by audioholic

Not sure how much energy is lost in the transformation of the energy from one form to another. Using a diesel bus may be more efficient than using the diesel to run a generator and charging an electric bus from the electricity generated from the generator. Guess thats similar to what is happening currently

Not necessarily. It depends upon what kind of engine you are using.
For example, lets say you have an engine that has max efficiecny at 2200rpm.
You can continously run this engine only at this RPM.
Electric motor has instant torque, so in stop and go traffic, it will be a boon.
you can use a gas turbine, and always run at 10,000 rpm i.e. max efficiency.

Therefore it does make sense to use a diesel generator, or any other Ic engine, esp in city vehicles.
When the battery is charged, you can switch off the diesel gen, and recover energy while braking.

I think london city bus is moving to this diesel electric thingy.

[audioholic]

Originally Posted by tsk1979

Not necessarily. It depends upon what kind of engine you are using.
For example, lets say you have an engine that has max efficiecny at 2200rpm.
You can continously run this engine only at this RPM.
Electric motor has instant torque, so in stop and go traffic, it will be a boon.
you can use a gas turbine, and always run at 10,000 rpm i.e. max efficiency.

Therefore it does make sense to use a diesel generator, or any other Ic engine, esp in city vehicles.
When the battery is charged, you can switch off the diesel gen, and recover energy while braking.

I think london city bus is moving to this diesel electric thingy.

I agree about the efficiency part. Even the Indian railways has their Locos running on similar technology without a battery. But here, power is generated somewhere, and its transmitted elsewhere, again received by the bus station and then the bus is charged and run with that electricity. So I just gave an example to consider how green or cheap it may be. If the engine is present in the vehicles, through a IC-Electric-Battery model, it will definitely be economical as you said. The IC engine can run when required and at its most efficient speed at all times and this can either charge the battery or drive the motors.

[Mpower]

Originally Posted by tsk1979

I think london city bus is moving to this diesel electric thingy.

Its called series Hybrid, with the Prius being a parallel hybrid.

London is just starting a trial now. NewYork transit started in 1999 and now operates a fleet of 800 Hybrid buses

http://www.nrel.gov/vehiclesandfuels...ybrid_nyc.html

[ajman28]

I have two points for clarification:

1. Battery:
What about the battery life? How long do these generally last? They must be quite expensive to replace, correct?

I was just thinking of a normal mobile phone battery. The overall backup when you buy a new one is about a day. This then becomes something like half-day in a year or so and you end up discarding it all together!

Does the automotive batteries (like the one used in this case) work on the same principle too?

If this is the case, then 7rs/km needs to be "re-calculated"!!!

2: Transmission:
How does the transmission work for buses like this?

[tsk1979]

Originally Posted by ajman28

I have two points for clarification:

1. Battery:
What about the battery life? How long do these generally last? They must be quite expensive to replace, correct?

I was just thinking of a normal mobile phone battery. The overall backup when you buy a new one is about a day. This then becomes something like half-day in a year or so and you end up discarding it all together!

Does the automotive batteries (like the one used in this case) work on the same principle too?

If this is the case, then 7rs/km needs to be "re-calculated"!!!

2: Transmission:
How does the transmission work for buses like this?

The battery lasts 6000 charge cycles. that is 250*6000 = 1.5 million kms
So at 15rs/km cost saving, you can see this is about 7.5 million rupees saved, or 75 lakh saved.

However, you have to realize that cost of fuel will keep going up, however electricity costs do not follow the same extreme raise cycle.

Moreover, electricity is a local resource, and fuel affects balance of payments. So its always better to have atleast a part of transport system replaced by electricity.

[srishiva]

About 60-70% of installed power generation in Karnataka is Hydro+Solar+Wind. However close to 50% of power is generated using these resources.

A plant to produce Methane from food waste was started a few days ago. If people in power use some common sense using appropriate fuels for different applications, it does reduce the carbon footprint considerably for public transport. Ofcourse private companies need to pitch in developing new alternatives aggressively also.

[Thilak29]

BYD finally hits Bangalore Roads.

[kamyfc]

Originally Posted by audioholic

^^ Absolutely. Unless the power is produced from Hydroelectric or Wind or such renewable sources. Since the majority of power is from thermal energy, I dont see anything 'Green' except that we may not have them smoking out our vehicle like the Marcopolo does

Our power sources must turn non polluting and renewable ones resource based and only then do these buses or electric anything will be cost effective or non polluting.

Not sure how much energy is lost in the transformation of the energy from one form to another. Using a diesel bus may be more efficient than using the diesel to run a generator and charging an electric bus from the electricity generated from the generator. Guess thats similar to what is happening currently

Typical comment from a OIL loving petrolhead.
How bout getting the facts right before posting stuff like this?

An electric motor is much more efficient than an ICE based engine as the ICE based engine dissipates so much energy as heat.
So even if the electricity generated is from Coal, this is a greener alternative as compared to blowing soot in our children's faces.

We also save much so much money spent on importing oil.

Hats of to BTMC to making this test happen!
I hope they procure these buses and make this a reality.

I have have blogged on the technical aspects of the BYD electric bus including details of the battery pack. I also have listed some alternative options that transport authorities could consider like the Trolley system.

This is a great move for sustainable transport in India!

[srishiva]

BMTC has floated a global tender for procuring 50 diesel hybrid buses and expects to have them running by 5 months.

[goingelectric]

There are quite a few technologies that allow even polluting power plants (e.g., coal fired, etc ...) to get a lot cleaner. For example, a lot of advance has been made in various carbon capture and storage (CCS) methods at the point source. These technologies work well only on a very large scale and hence trying to miniaturize them will not work on a small scale, for e.g., vehicle tail pipes.

Adoption of CCS methods at our power plants will more or less negate pollution, which then is a mute argument for those who claim that the source is only shifting from tailpipe to smoke stack.

Adoption of CCS notwithstanding the earlier we adopt EV tech the better it is for our Country on the long run, BMTC is once again doing a super job of thinking ahead! Kudos!

[itwasntme]

Excellent move to at least try it under real-life conditions in namma Autoluru.

However, I want to point out that if BMTC somehow enforces a eco-friendly driving style on their drivers, they can potentially save immense amounts of diesel and cause far far less pollution!

It pains me to see the way many BMTC buses are driven aggressively with totally uncalled for acceleration in too low a gear (i.e. at high engine RPMs) only to SLAM to a stop 20 metres at the next congestion point. A simple example are the poor Volvos which are usually found lurching and swinging wildly on their air suspensions because the nincompoop has (totally unnecessarily) locked the autobox in a lower gear rather than accelerating peacefully in D mode.

A saner green mode of driving will save money and also save our lives!

[Zed]

BYD seems to be ploughing ahead with its plan to sell e-buses globally.

Its LA bsed subsidary in North America recently won an order for ten buses from the long beach transit authority. A BYD e-bus successfully completed a two month evaluation by the NY Metropolitan Transportation Authority

I guess we will be seeing more of these e-buses. Kudos to BMTC for being the first state undertaking to evaluate and order these buses.

Completely agree that there is potential to save fuel through better driving habits - but I suppose thats easier said than done.

[S2!!!]

After BYD K9, Gujarat is also proposing to introduce introduce electric-powered vehicles in the public transport system.

The Gujarat Government has proposed to introduce a fleet of electric buses for public transport, which will shuttle between Gandhinagar and Ahmedabad. In the initial phase, 15-20 mini electric buses will be inducted to the fleet, with a seating capacity of 40 passengers each.

Link to News Article

[Pacifica]

Are these paid for by the JNNURM scheme?

[S2!!!]

Originally Posted by Pacifica

The buses in the linked news article are Bangalore city buses - how are they related to the news from Gujarat???

Sorry for the confusion. The picture is just for reference.