Jaguar Electric Powerboat: Time For Tea?
And they say water and electricity don't mix...
Now Jaguar is taking its EV knowledge to the water. With a little help from Williams, Jaguar Vector Racing has set its sights on an electric powerboat world record. And, well, they wouldn't have made a video about an unsuccessful record attempt, so here we get to see the record run on video. We'll keep the speed a secret for now though; wouldn't want to spoil the surprise...
The record run took place at Coniston Water, an iconic location in the history of British boat speed runs. While we may be some way off matching Donald Campbell's incredible feats of nautical velocity, how far off can it realistically be? Answers on a postcard please...
However the overwrought drama/sense of danger was a load of old bks. I could go out now and get in any number of commercially available fossil fueled speed boats and obliterate the speed they achieved here, and be back at the dock in time to pick up the deck fluff and cocktails.
To put it in perspective, I was involved with the running of an inboard-engined hydroplane that was running faster than this (circa 110mph) back in the 1980's... using a tuned Hillman Imp engine.
If Jaguar splurged media hype around the fact that their latest electric car was faster than a tuned Hillman Imp, would you be impressed?
No, me neither.
To put it in perspective, I was involved with the running of an inboard-engined hydroplane that was running faster than this (circa 110mph) back in the 1980's... using a tuned Hillman Imp engine.
If Jaguar splurged media hype around the fact that their latest electric car was faster than a tuned Hillman Imp, would you be impressed?
No, me neither.
My first thought was that from what I can tell radio controlled electric boats with brushless motors are a lot faster than their IC counterparts
Granted that’s due to mini engines etc, but I thought surely this can’t be it? I’d not have made such a sing and dance if I were Jag
Electric motors are very good at providing torque which is why electric cars can be made to go so quick. Boats don't require torque as such but just need to spin the prop as quickly as possible.
Someone feel free to explain it properly...
The drag of the hull in / on the water, and the amount of power needed to over come that, compared to a car running through air/on a road is going to be huge. Those really fast IC hydroplanes are all running on a cushion of air, with only their props in the water. An electric boat has to do the same to be as quick, but presumably its heavier (all those dratted batteries) and maybe the electric motors aren't so efficient at very high speeds either?
But ultimately it was a ten-year old record, and they only beat it by a handful of knots, despite battery technology supposedly having moved on significantly in that time. It may have been technically difficult, but it just didn't sound all that impressive.
A modern Unlimited Hydroplane is the world's fastest racing boat, capable of speeds in excess of 200 mph.
Yes I know this wasn't an 'unlimited hydroplane' but anything less than 200mph would be pants.
The previous record of 200mph had stood since 1962. It's not an easy record to break.
They certainly need to be looking for 120mph+, though, before they'll impress anyone in the powerboating world.
A typical high speed powerboat has a low mass and so it "Planes" easily, ie with a low hull drag. A heavy boat can of course still plane, or even "fly" (most racing power boats only have the prop and the rudder and a turn fin actually in the water) but the drag will be higher because the lift force required is higher.
Electric motors are very good at providing torque which is why electric cars can be made to go so quick. Boats don't require torque as such but just need to spin the prop as quickly as possible.
Someone feel free to explain it properly...
But as Max says, at high speed, hydroplanes frequently run with only the rudder and half of a surface-piercing propeller (not even their turn fin, on occasion) in the water. Trimmed properly, they're more WIG machines than boats.
We now have functional electric aircraft, and I'm pretty sure they fly faster than 89mph.
The problem is that Jaguar's commitment to breaking the record seems to go as far as bolting an electric outboard onto the back of an otherwise unmodified, standard Formula circuit racing hull. It's the equivalent of taking a Formula 3 car, fitting it with an electric motor and no other modifications, then using it for a straight-line speed record attempt.
Also probably worth pointing out that there appears to be an anomaly in the electric driven record. This happens; usually due to changes in UIM rules - for example the current record for the modern equivalent of those1-litre Imp-engined hydroplanes that we were running at 110mph back in the 1980's is now 89mph - but sometimes simply because someone claims a class record, but fails to claim the outright record (sounds dumb, I know, but you need to fill in the right paperwork to the UIM). In this case, the class speed record for 144V electric hydroplanes already stands 10mph higher than the 'outright' electric record that Jaguar appear to be claiming.
Electrical power is Volts x amps, so pull say 100A at 144V and you're pulling 14.4kW which is just ~19 bhp. So 190bhp would take 1000 Amps, and as losses are proportional to the current squared, that's a huge in-efficiency....
Is the class limited to 144v deliberately to slow these 'lecy boats down???
There are classes for 72V and 144V, just as there are classes for various piston engine sizes, gas turbines, and so on (and the gas turbine engined 'Unlimited' circuit racing hydroplanes aren't really unlimited any more; there is actually quite a complicated rule book and their engines are restricted to about 3,000 SHP... you wouldn't have such a restriction with a purpose-built unlimited immersed propeller record-breaker).
It so happens that a boat in the 144V class is also apparently the fastest electric boat in the world, at present - faster than the Jaguar boat.
The Jaguar boat, if it is aiming for the outright Electric record could have run whatever voltage it likes.
I don't know what voltage they using, but the video says that they're using Formula E batteries (I have no interest in Formula E, but Google suggests they run at up to 800V?), and it's the first application of this HV technology to boats.
ETA: The fact that someone with the 144V restriction has already gone faster than Jaguar has managed with much higher voltage makes their achievement even more lacklustre, of course.
This is the rudder and water pick-up on Jim Noone's British Unlimited Prop-driven Record Holder (~155mph in a 7-litre Chevy V8-engined hydroplane):
The 'short duration' record run involves accelerating to maximum speed and then maintaining it over a measured kilometre (twice - in opposite directions), so in fact involves running at peak power, full throttle for several minutes, which I suspect is something that a Formula E car never does.
300kW (~400bhp) would see you good for 140+mph in a well designed petrol-engined hydroplane, but but that's not allowing for the extra hydrodynamic and/or aerodynamic drag penalty from weight of batteries.
As I said earlier 120mph+ would be the threshold at which I'd have been willing to say 'good result'. Over 135mph and I'd have been properly impressed.
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