[obermd]

https://arstechnica.com/cars/2017/0...bus-just-drove-1100-miles-on-a-single-charge/

This is a huge step forward for removing ICE from our cities. The charging system for this bus will fully charge the bus in one hour.

 

[Mister Dave]

A few points I was looking for and didn't see....

Range fully loaded
Winter range
Charge rate (volts/amps)
Expected life of the battery


Oh, wait.....

Charging at 250-1000V (DC) and up to 1400A......

Smoke them cells!!! What size conductor do I need to pass 1400 amps? Let's see......

 

[obermd]

Somewhere in the article it says 1 hour for a full recharge and that the company is planning on putting their charging technology in the public domain. This rate of charging, if it could be scaled to POVs (Personally Owned Vehicles) would be a game changer for EVs.

Also, I think Ari-C has competition - the 1100 miles was at an average speed of 15 MPH. For a city bus this is probably about right for an average speed.

 

[Mister Dave]

This rate of charging, if it could be scaled to POVs (Personally Owned Vehicles) would be a game changer for EVs.

It would severely shorten the life of your battery. GM goes lowball on charging because they are required to warranty the battery 8 years, and in Kalifornistan 10 years. No way would you see them setting themselves up to replace everyone's battery at least once for free.

Even Tesla throttles fast charging at a certain point.

A new battery technology will have to come along to allow such a thing. Even then I'm skeptical. 1400 amps is insane at any voltage.

 

[Upper5Percent]

Somewhere in the article it says 1 hour for a full recharge and that the company is planning on putting their charging technology in the public domain. This rate of charging, if it could be scaled to POVs (Personally Owned Vehicles) would be a game changer for EVs.

Also, I think Ari-C has competition - the 1100 miles was at an average speed of 15 MPH. For a city bus this is probably about right for an average speed.

https://arstechnica.com/cars/2016/07/proterra-develops-fast-charging-for-buses-opens-up-the-patents/

Proterra's high-voltage overhead charging system uses robotic control (and some autonomous software on the bus) to replenish bus batteries in as little as 10 minutes, depending on the size of the battery pack. Charging at 250-1000V (DC) and up to 1400A, the system is eight times faster than the CHAdeMO fast-charging standard and between three and four times faster than Tesla's Superchargers. And unlike the old-fashioned pantograph, which needs to cover the vehicle's entire route, Proterra's system is static. This means bus operators can install them in terminals or at the same locations they use to refill their diesel tanks.

Some back story to bus electrification...

http://www.siliconinvestor.com/readmsg.aspx?msgid=30708684

 

[Mister Dave]

Very interesting. I looked at the Wikipedia page and found it to be a Proterra brochure. But the interesting part is that I'm finding discrepancies between Proterra's claims on buses in use, and some the transit authority's pages. VIA Metropolitan Transit (San Antonio, TX) lists one Proterra BE35 EcoRide in use. Proterra's Wikipedia page says they have 3. Transit Authority of River City (Louisville, KY) lists none while Proterra says they have 16.

This company runs on taxpayer funded grants and venture capital (which includes GM and BMW) as far as I can tell.

 

[Mister Dave]

.....and that the company is planning on putting their charging technology in the public domain.

On their site I find the idea that charging stations would be placed at bus stops for 5-13 minute charges.

OVERHEAD FAST-CHARGERS
Proterra on-route charge stations enable 24-hour circulator route, opportunity charging. Specially-designed batteries for the Catalyst FC can charge in 5-13 minutes, enabling 24/7 vehicle operation. Charge stations can be installed at curbside pullouts, transit centers or bus stops. Assisted automatic docking uses wireless communications to govern the speed and stop location of the bus and connects the charger with no input required from the driver, making it simple and safe.

It's been a while since I used a transit bus, but I don't remember any 5-13 minute stops. I guess folks may have to adjust their commuting times.

 

[obermd]

On their site I find the idea that charging stations would be placed at bus stops for 5-13 minute charges.

It's been a while since I used a transit bus, but I don't remember any 5-13 minute stops. I guess folks may have to adjust their commuting times.

At end terminals busses will sit up to half an hour when they arrive on time. Bus schedules usually have some slop factored in for traffic delays.

 

[Mister Dave]

Well, stopping for wheel chair bound people might take a few minutes. Most buses are required to have a kneel function for this.

I just don't know if there's going to be money for these bus stop chargers. Ripping up streets/sidewalks is pretty expensive in addition to the equipment and added electrical lines.

 

[obermd]

Well, stopping for wheel chair bound people might take a few minutes. Most buses are required to have a kneel function for this.

I just don't know if there's going to be money for these bus stop chargers. Ripping up streets/sidewalks is pretty expensive in addition to the equipment and added electrical lines.

I don't know about other cities, but Denver seems to always be ripping up streets for other reasons. Why not lay down the cabling needed at the same time? Yes, not all of it can be installed this way but a large amount can. Also, many cities use large underground runs for utilities and there's space in those runs for the power cables needed.

 

[Mister Dave]

I don't know about other cities, but Denver seems to always be ripping up streets for other reasons. Why not lay down the cabling needed at the same time? Yes, not all of it can be installed this way but a large amount can. Also, many cities use large underground runs for utilities and there's space in those runs for the power cables needed.

LOL - Ever watch city workers in Oakland Ca. work on a sidewalk? We did once just for laughs. You might get it done in a few decades.

Don't even think about tearing up a sidewalk in New Jersey unless you have a few million to spend. No one knows why, but every project costs triple there.

So I guess one should choose well in locating these things.

 

[wizard_of-ahs]

LOL - Ever watch city workers in Oakland Ca. work on a sidewalk? We did once just for laughs. You might get it done in a few decades.

Don't even think about tearing up a sidewalk in New Jersey unless you have a few million to spend. No one knows why, but every project costs triple there.

So I guess one should choose well in locating these things.

Because of the bribe money, silly

 

[hellsop]

It's been a while since I used a transit bus, but I don't remember any 5-13 minute stops. I guess folks may have to adjust their commuting times.

Sensible route management needs at least one layover point, often near the endpoint of a route. The time allows a bus running late to leave on time, often gives drivers the opportunity to deal with ... necessary bodily functions, etc. The hazard I see is that dropping a charge station on a layover point means that the layover no longer serves as a schedule buffer. A bus that's 10 minutes behind schedule, with a scheduled 13 minute layover, can leave after three minute and it's back on time again. A bus that needs to charge for 10 minutes is still 7 minutes behind when it can finally roll out again.

 

[Barry]

^ That's a valid point, but could be easily solved by lengthening the layover intervals or having enough battery range to accept some shortened or missed charging opportunities. Not an insurmountable problem. Certainly easier than the other problems like affording the cost of the BEV busses or the installation of the charging equipment.

 

[obermd]

^ That's a valid point, but could be easily solved by lengthening the layover intervals or having enough battery range to accept some shortened or missed charging opportunities. Not an insurmountable problem. Certainly easier than the other problems like affording the cost of the BEV busses or the installation of the charging equipment.

Or just using these layover points for opportunistic charging with the main charging occurring at the depot at night.

 

[Mister Dave]

Or just using these layover points for opportunistic charging with the main charging occurring at the depot at night.

I think this might be the more sensible plan overall.