
F1 Tech Is About to Make Buses More Efficient - srikar
http://www.wired.com/2014/07/f1-kers-london-buses/
======
exDM69
Formula 1 cars have energy recovery for kinetic energy (regenerative braking)
and thermal energy (motor generator unit in turbocharger shaft). Both of these
technologies have potential to be used for buses and other heavy vehicles that
move in an urban environment.

As an example, my regular bus route is 50% highway at 80 km/h and 50% urban
start-stop traffic. The city buses have a huge turbo diesel or natural gas
engine, and the turbo takes about 3 seconds to spool up. At 80 km/h, drivers
tend to be pumping on and off the throttle, purging the turbo pressure
repeatedly. This is horrible for fuel efficiency.

Ideally, an electric motor should do the initial few seconds acceleration,
while the turbo is being spooled up using the electric motor attached. When
the turbo is spools up, the internal combustion engine should be slowly
introduced by adding fuel according to the correct stoichiometric ratio. At
cruise speeds, engine power could be regulated by harvesting energy off the
turbine rather than pumping the gas pedal which purges the whole turbo.

A city bus should be able to operate at or near optimum stoichiometric
conditions at all times, saving a ton of gas and emissions. Currently there's
a huge puff of black diesel smoke every time the bus leaves a bus stop.

These are very exciting times for anyone who is interested in motor sports
technologies applied to efficient transport.

~~~
fr0sty
>city bus should be able to operate at or near optimum stoichiometric
conditions at all times

Diesel motors operate quite differently than gasoline engines in this regard,
actually. A diesel motor is only operating at the correct stoichiometric ratio
at full throttle and is running lean for the rest of the time because there is
no throttle plate to modulate air intake and power is only modulated by the
quantity of fuel injected into the cylinders.

~~~
cynicalkane
Because diesel fuel burns as soon as it's injected, you don't even want a
stoichiometric ratio of fuel because you can't get an even air-fuel mixture.

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erjiang
I just pulled numbers from some of the public transit buses that DoubleMap
tracks. I see annual usage of 40k-50k miles on a single bus. Given 2013's
diesel prices and standard diesel bus efficiency, that might be about $1/mile,
so let's say $50k/yr in fuel for a single bus.

If they claim to save 20% on fuel, then a single bus would save about $10k/yr,
and if the system can pay for itself in three years, then it would cost about
$30k.

These mileage numbers aren't for London, so that estimate could be off by
quite a bit. Still, consider than a standard diesel bus may cost $250k in the
US while a hybrid 40' bus could cost $600k,[1] and this looks like a great
deal.

[1]
[http://www.intercitytransit.com/SiteCollectionDocuments/hybr...](http://www.intercitytransit.com/SiteCollectionDocuments/hybrid-
fact-sheet.pdf)

~~~
erjiang
I should add that driving in dense urban areas means fewer miles, lower speed,
and more frequent stopping and starting, so the savings in a smaller city
would be smaller.

~~~
wlesieutre
More frequent stopping and starting would actually be an advantage here. If
you're driving a long route between bus stops and don't brake frequently,
you're only taking energy out of the flywheel when you initially get up to
speed, and you're only putting it back in when you stop at the end.
Regenerative braking is a lot more valuable in stop and go traffic. Every time
you accelerate out of a stop light you're burning less fuel.

~~~
erjiang
Right, that's why I said in a smaller city (less dense, more long stretches of
roads) there would be fewer savings from a flywheel or hybrid.

~~~
wlesieutre
So you did, I must have misread your comment before.

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bgarbiak
Just a note: the system was never actually used in any Grand Prix. Williams
had problems with packaging and weight balance (safety was also a concern).
They later followed other teams and settled on battery-based solution.
Flywheel had only one significant advantage over these: lower operating costs.
That's what makes it feasible for use in public transport, I guess.

~~~
gsnedders
The R18 e-tron quattro, now three times winner at Le Mans, actually uses the
Williams Hybrid Power flywheel system — so it might not have F1 pedigree, but
it certainly has top-level motorsport pedigree.

------
josh-wrale
Volvo is on a similar path: [http://www.extremetech.com/extreme/154405-volvo-
hybrid-drive...](http://www.extremetech.com/extreme/154405-volvo-hybrid-
drive-60000-rpm-flywheel-25-boost-to-mpg)

------
Gravityloss
Why now? Flywheels have been around for a hundred years... meanwhile,
batteries have improved a lot.

There have been long articles about flywheels every now and then, yet you
never see them in buses.

[http://discovermagazine.com/1996/aug/reinventingthewh842](http://discovermagazine.com/1996/aug/reinventingthewh842)

~~~
InclinedPlane
Formula 1 was changed recently to encourage development of high efficiency
automotive technology. That change has apparently already started to pay off.

~~~
Gravityloss
Yes, that's possible. But no technical reasons are presented on why it should
happen now - compared to all the false prognoses in the last fifty years or
so.

~~~
InclinedPlane
Technical problems tend to fall rather more rapidly when billions of dollars
in R&D spending is put into play. Just the top 10 Formula 1 teams spend
something like $4 billion annually, and now a significant amount of that is
being funneled toward research on highly efficient vehicles.

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adambard
First hydroelectric water towers, and now vacuum-sealed spinning flywheels?
Come on, batteries, get it together!

~~~
adolph
The emergence of kinetic energy storage in the shadow of chemical storage is
pretty interesting. Oftentimes I think of progress as moving away from
mechanical things and toward electrical solid state things.

------
yread
Hm 60kg flywheel spinning at up to 36000rpm. What if it fails? I hope I won't
be anywhere near the tangent

~~~
valarauca1
A standard engine is a ~300lb block of iron containing 8-10 fuel air
explosions per second. If so much as a piston rod gets over stressed its
capable of destructively disassembling itself in a blink of an eye.

A jet turbine rotate at speed in excess of 50k rpm. In the event a blade broke
off, it could sale though the outer casing, your body, a cement wall, before
you could hear the engine exploding.

Yet... that's perfectly safe. All I'm saying is mechanical engineers are VERY
good at their jobs.

~~~
yread
Sure it's reasonably safe, not perfectly safe.

In diesel engines, if there is a runaway and it isn't stopped the shaft can
get overstressed and literally explode.

Jet engines are specially armored not to let any part of the turbine escape
the casing in case things go wrong (yet it still happens
[http://www.avherald.com/h?search_term=uncontained&opt=0&dose...](http://www.avherald.com/h?search_term=uncontained&opt=0&dosearch=1&search.x=0&search.y=0)
quite a lot one might say). And quite a lot of R&D was put into it not
happening.

Is there enough R&D being put into the flywheel not failing?

EDIT: my point is that stuff that is OK in a racing car might not necessarily
be safe enough to put on a bus or a tram

~~~
valarauca1
The R&D for a race car (especially an F1) is often far more advanced then that
of a buss. In F1 it literally pays to have the best testing equipment, the
best labs, etc. F1 prides itself on being as close to the cutting edge as
their rules lets them.

The famous saying, "To earn a small fortune in F1 racing, you must first spend
a large one." Is very telling of this. F1 isn't done to make F1 go fast, its
done to make other cars go.

:.:.:

A standard durability cell for engine testing for a production engine
component will typically have a ~20-30 year old sensors, and 15-20 year old
data acquisition system.

F1 all components will likely be <5 years.

------
Lagged2Death
[http://en.wikipedia.org/wiki/Gyrobus](http://en.wikipedia.org/wiki/Gyrobus)

Motorsport is arguably a latecomer to mechanical batteries, which have been
used in vehicular, transport, industrial, and aerospace applications for a
long, long time.

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lucaspiller
Just upgrading to newer busses would probably help. Most of my local bus
company's (First) fleet are S reg, so 16 years old.

~~~
astrodust
Most companies run these things into the ground. 16 years for a bus is like 2
years for a car.

~~~
gsnedders
And while they often disappear from major cities after about 15 years, they
just get handed down to more rural routes where they'll keep going till they
die.

