Volvo Officially Launches 7900 Plug-In Hybrid Bus (w/video)

SEP 22 2014 BY MARK KANE 24

Volvo 7900 Plug-In Hybrid Bus - drivetrain

Volvo 7900 Plug-In Hybrid Bus – drivetrain

Volvo Buses released a lot of details on its new 7900 plug-in hybrid bus, which will debut at the International IAA Commercial Vehicles show.

This extraordinary vehicle is designed to operate most of the time in all-electric mode, which could reduce fuel consumption and carbon dioxide by up to 75%, and total energy consumption is reduced by 60% compared to a conventional diesel bus.

It will be propelled by a 150 kW electric motor with 1,200 Nm of peak torque combined with 240 hp/918 Nm Volvo D5K 240, 4-cylinder, in-line diesel engine with common rail injection.

For energy storage, Volvo uses a 19 kWh lithium-ion battery pack equipped with a heater/cooler system. This could be enough capacity for 10 km and, on average, 70% of the distance between charging stations.

Volvo 7900 Plug-In Hybrid Bus - drivetrain

Volvo 7900 Plug-In Hybrid Bus – drivetrain

Volvo 7900 Plug-In Hybrid Bus

Volvo 7900 Plug-In Hybrid Bus

Volvo Buses believes in using a rapid charging system many times a day at bus stops. A new special roof system was presented, which will be able to fully charge the 19 kWh battery pack in roughly 6 minutes.

The Opportunity Charging System can provide up to 400 A at 750 V, which is some 300 kW.  However, the plug-in hybrid bus will accept just half of this.

There is no range problem as the Volvo 7900 plug-in hybrid can operate in regular hybrid mode too.

Håkan Agnevall, President Volvo Bus Corporation stated:

“I am very proud to launch this ground-breaking bus system. Electric-hybrid buses and full-electric buses are tomorrow’s solution for urban public transport. They will allow us to reduce energy consumption, air pollution, climate impact and noise, which are some of the biggest challenges facing large cities worldwide.”

One of the benefits of plug-in hybrid buses is the noise level reduction.

Several cities already ordered the new Volvo 7900 plug-in buses.  However, series production isn’t scheduled to begin until 2016.


Length12 m
Width2.55 m
Height3.28 m
Permitted GVW19,000 kg
Emissions standardEuro 6
Diesel engine240 hp/918 Nm Volvo D5K 240, 4-cylinder, in-line diesel engine with common rail injection
Electric motor150 kW/1200 Nm Volvo I-SAM
Energy storage systemHigh-capacity lithium-ion battery
TransmissionVolvo I-Shift automated gear-changing system
Charging systemOpportunity Charging. Fully automatic fast charging sequence. Rapid charge time: up to 6 min.
SuspensionElectronically controlled air suspension with kneeling function
Passenger capacityUp to 95 persons, 32 + 1 (folding) seats
Door systemElectric. 2+2+0 or 2+2+2.
Climate system28 kW AC with separate climate zones for driver and passengers
Volvo 7900 Plug-In Hybrid Bus

Volvo 7900 Plug-In Hybrid Bus

Volvo 7900 Plug-In Hybrid Bus

Volvo 7900 Plug-In Hybrid Bus

*Editor’s Note: We strongly suggest that Volvo reproduces “The Epic Split” featuring this new 7900 plug-in hybrid bus.

Categories: Bus, Volvo

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24 Comments on "Volvo Officially Launches 7900 Plug-In Hybrid Bus (w/video)"

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“Allowing people to open their windows and enjoy”:

not having to smell a stinky diesel.

Looks like a decent bus but it should be running on CNG as fuel for the range extender.

It should run on untreated biogas for the range extender to be cool/green.

What’s wrong with 100% HVO diesel from renewable fuels? 🙂

Boxy, but not a pure BEV. Diesel for an urban bus is dumb. Thumbs down.

Ahh. I knew the purists would speak.

The heavier the hauling, the higher the requirement for a fuel that is denser than a battery.

I wonder what the endurance of a BYD bus is up a 6% grade?

I bet it’s not very good. I’ll have to calculate it.

Hydrogen hybrids seem to work well for mountainous terrain:

How much it costs is another thing, which I don’t have data on.

Just for fun I ran the numbers for the BYD bus.

Looks like it would have a 48 mile endurance on a 5% grade. (If I’ve calculated it right).

Not too bad.

Why not put a 30KWh battery instead of one that only gets you 70% of the way to the next charger? Seems like 11KWh could be had for the cost of a 4 cylinder diesel..??

Yeah, it’s not like chargers ever have problems. I’m sure the locals will understand the bus line not operating on a particular route for a week or two while they make/fly out a proprietary charger component that fails at one of the stops.

Diesel makes it reliable, and allows it to tolerate problems like localized electrical failures, charging station failures, etc. Even if you doubled the capacity, it may not be large enough to handle a single charging station outage. As it is, it allows customers to test electrification without committing to an unknown product. I’d imagine it costs less as well, since you not only need to increase the battery size, but also need to increase the charging speed, you can’t simply have the bus stop for a longer period of time. This may not be feasible in many bus stop locations with existing infrastructure.

I think the BYD bus has 300 kwh (approx) and supposedly it sells for only around 550K $ vs 400 K$ for a std Diesel bus.

Sounds too good to be true but I really don’t know.

I think the whole bus thing is very interesting though.

I also think c4v3man has some good points.

Hilarious that they’d photograph the hybrid bus sitting in a Culver City Plaza, next to seated outdoor diners. Diesel exhaust is the last thing you want served with your food…

They are in all electric mode Anon.
There’s no exhaust.

Jay Leno drives the Protera Bus on Jay’s Garage

Here’s another Bus episode from Jay’s Garage.

These buses are put together by a company called Complete Coach Works. What they do is take old buses and refurbish them and install electric motors and lithium phosphate batteries. Cities thus have the option of converting old city bus fleets without having to scrap the old but still usable buses to buy expensive brand new ones.

Coach Works refurbished buses are designed for daily routes less than 100 miles. Jay Leno says a reconditioned bus from Complete Coach Works is about 1/4 the price of the brand new Protera Ecoliner bus.

The Protera buses are charged overhead just like the Volvo 1900 hybrid buses.

Reconditioned buses from Complete Coach Works on the other hand are designed to operate all day without recharging.

That sounds cost effective, and in terms of life cycle emissions it is way more effective to find ways of refurbing old vehicles.

Great posts jmac.
I still love the Proterra bus.
I think BMW should build the next structure for the bus out of CFRP.

Well his pricing for the used bus seems a bit high, but then all electric busses seem to be a bit overpriced, so more and more companies like BYD, etc coming out with totally electric drivetrains (If the heater has to be propane thats ok with me – but this used bus apparently tries the heat pump function of the air conditioner first). THe more companies that make these, or convert used busses, the lower the price will ultimately be, and the more BEV busses will be online. I don’t know what volvo is thinking with that convoluted plug-in hybrid mess with the silly plug in infrastructure at the bus stop. Its as if they don’t understand why plugin hybrid’s came about in the first place – the Volt has a 40 mile battery, but people need assurance that they can drive more unexpectedly so the gas engine allows another 300 miles, usually for emergencies. But the car is primarily electric. This silly Volvo has a puny 19 kwh battery (microscopic compared to the bus’s cost and size), and then you’d have to spend a fortune to recharge it. Just spend the money and put a 500 kwh battery on… Read more »

When it comes to commuter buses, total on time is probably more important than total drive distance. I’ve been stuck in a bus in the Lincoln Tunnel for 30 minutes while a stalled vehicle gets towed out of the tunnel. If you’re going to use an electric only bus for NY commuter transportation it better be able to stay on with HVAC running for at least 2 hours.


I agree Nelson,

As a Volt owner I think the EREV bus concept is even more valueable on the bus level.

But I like the Proterra bus too.

I think it’s about what your duty cycle is for the bus.

Shorter range = electric

longer range = Hybrid

It just pisses me off that they didn’t add that extra battery capacity to make sure you could go 100% electric for most of the time.
And then they could use the full 300kW when fast charging too, so it would still take about 6 minutes.

But I wonder what the real world range will be. It seems like a normal number for BEV buses seem to be 0,9-1,2 kWh per km.
Then this one should rather be able to go 16-21 km per charge.

But it’s common for Volvo to downplay the numbers and advertise numbers that you will reach and go above under all conditions.

Got any news on Volvos all electric bus by the way? They are supposed to be in trafic by next summer so there should be some info at least.

The Chinese made a good move buying Volvo!

Well. Volvo is a very big company that is not owned by the chinese. So the chinese have nothing to do with these buses.

Volvo cars on the other hand was a small part of the “real” Volvo company until 1999 when Ford bought that part of the operations. Then the chinese took over the majority share fron Ford.

But the chinese that bought the Volvo cars hve been smart. Much smarter than Ford.

Basically they have just put in money and made sure that the engineers in Gothenburg has only needed to focus on what they do best, build great cars and research and develop for the future great cars.