Opbrid Introduces New Overhead Fast-Charging System for Buses; Leveraging Lithium Titanate (nLTO) Battery Technology for Rapid Charge Hybrids
06 October 2010
|The Bůsbaar rapid charger. Click to enlarge.|
Spain-based Opbrid Transporte Sostenible S.L. has introduced the Bůsbaar—an overhead, pantograph-based fast-charging station for buses. Based on technology from the European rail industry, and leveraging the rapid charge capability of nanotechnology Lithium Titanate (nLTO) technology batteries such as those from Altair Nano, the Bůsbaar is a high power (~250 kW) opportunity charging station that rapidly charges a bus at one or both ends of its route.
By fast charging these batteries for 5 or 6 minutes at each end of a bus route, a bus can run throughout the day on 100% electricity from the grid. This enables the upgrading of many hybrid-electric buses to use up to 100% electricity from the grid instead of diesel, Opbrid says. Opbrid calls such buses Rapid Charge Hybrids (RCH).
Built by Swiss electric rail supplier Furrer+Frey and Germany’s Schunk, the Opbrid Bůsbaar can be installed easily in any location, since it is unobtrusive and swings away from the road when not in use. The Bůsbaar can be installed in days at a fraction of the time and cost for installing an electric tram or trolleybus system. Opbrid has also partnered with Epyon on the fast charger.
With this system, it is possible to change most of the urban bus systems in the world from petroleum to electricity simply by changing diesel buses to fast charged hybrids and installing these charging stations. We can do this now, and we need to do this now.—Opbrid CEO Roger Bedell
The Opbrid Bůsbaar was designed to provide a large target for docking the bus to the charging station. This large physical target makes it easy for the bus driver to line up the bus to the charging station in all types of weather and situations.
All electrical connections are overhead to eliminate high voltage risks, and reduce vandalism. To avoid any possibility of collision between the roadside portion of the charger and tall vehicles, the charger swings away from the road when not in use. Additionally, the charger is electrically grounded when retracted, providing a further layer of safety protection.
Roger Bedell (2009) A Practical, 70-90% Electric Bus without Overhead Wires (EVS 24)
Brilliant! I've had a similar idea for years that used capacitators and a charging station at each stop in a high density city such as New York or Chicago.
Posted by: GreenPlease | 06 October 2010 at 07:56 AM
This is much better than having enough batteries for 8-hr runs. A typical city buss could recharge 8 to 10 times a days while the bus is being cleaned and the driver is having a smoke or quick lunch to keep him/her in a better mood.
Cleaner buses, happier drivers and users, no imported crude oil derived liquid fuel consumption, less noise, less GHG etc. How better can it get?
An emergency NG or ethanol APU could be added at little extra cost.
Posted by: HarveyD | 06 October 2010 at 08:41 AM
It is a brilliant application for the Titanate type of lithium battery that is extremely durable capable of over 10000 deep cycles. Such durability is not needed for most EVs but it will be needed here where a battery may be cycled almost fully 10 times a day 300 days a year. It should also be cost competitive to other types of EV or diesel busses as the needed size of the battery can be kept very small or just enough to do one bus route (20 miles range should needs less than 40kWh of batteries). However, I think Toshiba will take most of the market for this type of applications as they are currently the only producer with mass production capability for the Titanate type of lithium battery see http://www.greencarcongress.com/2010/09/toshiba-20100930.html#more
Posted by: Account Deleted | 06 October 2010 at 08:57 AM
The range extender makes sense. Put a diesel genset in running on CNG and they would cut fuel costs, pollution and noise.
Posted by: SJC | 06 October 2010 at 09:04 AM
@ SJC & HarveyD, why does everything need a range extender? Practical engineering and economics are the key. This one energy storage/conversion system will be expensive enough. A bus is not a Swiss Army knife. A well engineered, economic version of this concept should have plenty of applications without making a Frankenstein-mobile.
Posted by: Tim Duncan | 06 October 2010 at 10:06 AM
My suggestion was not really a range extender per se but rather an emergency APU to keep essential subunits energized when main power is out. However, dual use could be an asset.
Posted by: HarveyD | 06 October 2010 at 10:17 AM
A natural gas based heating system for operations in cold weather climates might make economic sense as a large bus in cold weather could draw 20kW just for heating and therefore require a much larger battery. There is zero need for a combustion engine for anything. Should the main battery fail you only need a small backup battery (less than 1kWh) to operate power steering, lights, brakes and doors.
Posted by: Account Deleted | 06 October 2010 at 10:57 AM
I like the idea of a zinc air fuel cell powered bus better than this. Potentially, with zinc air, you only refuel perhaps once a day and have significantly more range, and would only need a fraction of the number of charging stations as you would need with this system for a fleet of buses since changing out batteries would be faster than parking and waiting for batteries to charge. Henrik brings up heating and cooling which need a lot of extra energy, which the story doesn't really discuss.
Posted by: ejj | 06 October 2010 at 11:07 AM
You could squeeze in a 4 cylinder diesel spinning a 30kW generator and 20kW of heating if required.
Fully electric would be better, if the batteries can cope with it then even better.
Posted by: 3PeaceSweet | 06 October 2010 at 11:22 AM
Obrid is based in Spain and therefor not immediately in need of heating interiors. But for most EU cities they will need to have some sort of climate system separate from the traction batteries.
CNG is a clean if not sustainable solution until batteries improve enough to also power heating and cooling. Likewise an alcohol FC if there is alcohol readily available.
This is a terrific breakthrough for public transport. Altair has been bought by a Chinese company who will hopefully invest heavily in mass production of titanate batteries. That will provide a good second source for titantate chemistry on the world market.
I can hear it now... Florence without the dastardly noise of mopeds and diesel buses spewing black carbon particulates! Peace. Quiet. Life!!!
Posted by: Reel$$ | 06 October 2010 at 11:44 AM
HVAC (heating and cooling) could be supplied with ultra high efficiency Heat Pumps. Braking energy capture could supply most of the e-power required for HVAC on AWD stop and go city buses. Roof mounted solar panels could (soon) help to reduce the size of batteries. A few years down the road, when batteries performance are 2x to 5x todays, four to five quick recharges a day should do it. Flexible Modular battery packs would not need back ups.
There's a great future for city e-buses of various sizes.
Posted by: HarveyD | 06 October 2010 at 12:30 PM
I WAS referring to a range extender as the total solution. You would not need charging stations at all and could increase mileage substantially without lots of batteries.
Posted by: SJC | 06 October 2010 at 01:24 PM
Harvey solar panels would help a little when the sun shines. However, the bus needs to operate also on a cloudy day or at night so adding them will not help to reduce battery size at all. Plus 20 sq meters of 20% efficient solar panels only adds between 0 and 4000W and cost about 24.000 USD so they are out of the questing for any commercial bus service. The titanate type of lithium battery costs about 2000 USD per kWh from Altair and Toshiba could probably sell them for 1000 USD per kWh to large bus makers like Volvo, Mercedes or Fiat but smaller customers will still pay 2000 USD per kWh. A cheaper alternative may be A123 systems LiFePO4 batteries but they may not be durable enough for this type of application. Also you keep talking about better battery performance will solve all problems. This is wrong. Batteries already exist that can do the job for almost anything and certainly this bus application. The cost per kWh is a far more important showstopper than battery performance. Reducing costs are vital and that is not going to change until we get some volume going and this is why the EV industry needs to be subsidized in the beginning.
Posted by: Account Deleted | 06 October 2010 at 01:27 PM
The urban bus fixed route is a tremendous opportunity to bring Lithium Titanate (nLTO) cell production to mass scale and less expense than fossil fuels.
Posted by: kelly | 06 October 2010 at 02:39 PM
A charging system like this one was used by a company in the 1950's to charge up their flywheel bus. I believe it was tried in Sweden and also they had a system in Zaire. Because flywheel technology was not very advanced, the systems were not in service very long.
Posted by: Big Al | 06 October 2010 at 02:58 PM
This system may be an interim approach to electric transportation until better
power storage systems appear. In North America we do have much longer routes.
A solution to this would be to have overhead bus bar power available on long
staight stretches which the bus would reach up to automatically. This could also be available on steep hills to top up the charge also.
Posted by: lestrin | 06 October 2010 at 03:12 PM
If you have 10 bus lines and need at least 10 high power charge stations at say 2 million dollars each. That could buy you 40 range extended diesel electric DME powered buses.
Posted by: SJC | 06 October 2010 at 03:54 PM
Does anyone know of a bus maker that makes composite busses? It seems like carbon fiber could be used in a lot of the components to help keep down weight and therefore the size of the batteries needed.
I'm not sure what the hoopla is about a climate control system... at least heating. I used to live in Chicago and still go back there several times a year. During the winter, if I'm riding a bus, chances are I'm dressed to walk outside: several layers and thick jacket. The last thing I really need is heat on a bus. To be frank, I'd prefer it if they didn't heat the bus because I usually start sweating as soon as I step on one in the winter. The clothes people wear and their own body heat in a confined space should be more than enough to keep everyone comfortable.
Air conditioning... that's a different story. You definitely need AC in a bus and that's going to suck down a fair amount of power.
I think what it really comes down to is cost per cycle or cost per mile all in. If the altair/toshiba batteries cost twice as much as the a123 batteries but last 3x as long then they'll win out by a healthy margin on an economic analysis.
One of the major downsides to this design is that it trades battery capacity and cost for additional charging stations. Also, this would add variability to the grid instead of taking it away. I can't imagine any utility company would be very happy knowing that there are 200+ busses roaming around their grid that, at almost any time, could hook up and suck down 200kw
Posted by: GreenPlease | 06 October 2010 at 04:23 PM
This is where the genset comes in, portable power. The engine cooling system could store enough heat for the bus parked for hours. The AC could be driven off the engine cooling a thermal mass as well.
Posted by: SJC | 06 October 2010 at 05:35 PM
This is what I promoted 4 years ago right here.
I like the idea of an APU for heat and backup. Contrary to Henrik's position, the same conditions which call for heat often put heavy demands on the traction battery (pushing through snow). Instead of over-sizing the battery for exceptional conditions, the APU would cogenerate heat and electric power. It would also allow extra options in blackouts; a battery-only bus would have to stop and wait for the grid to come back, but a bus with an APU can continue limited operations while its fuel holds out.
SJC, you have to be quite the methanol partisan to think that an overhead arm with contacts would cost anything close to your figure.
Posted by: Engineer-Poet | 06 October 2010 at 05:57 PM
Actually it's an expensive solution because of the use of powerful diesel engine and generator.
A much cheaper solution would be pure electric, with some towing trucks on stand-by if electric buses break down. The buses would also be lighter.
Harvey mentioned that Hydro Quebec was testing some batteries that can sustain 20,000+ charges (don't know at what rate of charge).
Instead of doing the charge for 5-6 min at max load to the grid and batteries (not good for either of them), it would make sense to extend charging period (ie charge at reduced power) if the bus stop lasts longer (say 15 to 20 min). Driver could enter/select the duration of charging period, or it could be done automatically based on bus schedule.
By splitting long bus routes into shorter ones, the system coverage could be increased.
Posted by: MG | 06 October 2010 at 06:14 PM
"Powerful diesel engine"? You're as far off-base as SJC's $2 million pricetag on an overhead arm with contacts.
Posted by: Engineer-Poet | 06 October 2010 at 08:50 PM
Its only talking about 10-15 km of range per charge not 20 miles. This is strictly to enable some very short routes to be totaly electric powered simply via a converted hybrid bus and a changing station which admittedly is likely 4-500k or more in cost but still one hell of alot cheaper then most electric mass transit systems.
But again its for VERY short ranges. Also even with those batteries they are likely to eat through packs fairly often given how many times a day they likely will be charged.
Posted by: wintermane2000 | 06 October 2010 at 10:45 PM
This is what I've had in mind for urban buses for years.
The Russians used to do this using ultracapacitor-equipped buses (yes really).
Posted by: clett | 07 October 2010 at 01:36 AM
Wow, lots of very good ideas here in the comments! Thanks! - The charging stations are more in the range of 300k, not 2 million, and can be shared by a number of buses, and last practically forever.
Dear Mr. Engineer-Poet, looks like you were already on the same road that I took about a year later. You said in your post "So yeah, I see these things taking off just as soon as some smart cookie finds a way to integrate a hands-off fast-charging system with a covered bus stop.". Hopefully I'm that cookie!
We've done a fair bit of analysis, along with Epyon, that predicts a reasonable battery lifetime of 6-10 years for a one-way route of 14km, charging at each end of the route. This assumes that the batteries can be kept around 25 degrees Celsius. Lifetime goes down dramatically if the batteries heat up.
The E-Traction bus in the video has a small 50kW VW diesel range extender, which should be plenty to run the bus indefinitely on diesel if required. However, with fast charging, the range extender shouldn't be needed very often. It's not very expensive, and makes the system much more flexible than a pure electric bus (like ProTerra). There are several other companies with suitable hybrid systems that can be converted easily.
As to heating - we are looking at a system in northern Sweden, and this is a big issue. Electrically heated seats was one suggestion, but I know what you mean GreenPlease, buses are typically overheated because the driver is in shirtsleeves, and the passengers in heavy coats. Here in Spain it is the opposite, AC is the issue, both for the people and for the batteries( Hmm, which one takes precedence on really hot days?)
Anyway, please send me any more suggestions and contacts, and forward this post to anyone you know. - Roger
Posted by: Opbrid | 07 October 2010 at 02:30 AM