Question Genesis 3.1 vs Cuda X Tech - efficiency and range?

[stuartv]

I was comparing specs on scooters.

The Genesis 3.1 and Cuda X Tech are basically the same length (24") and weight (34#).

The Genesis has 850 W-Hr of battery.

The Cuda X Tech (with the biggest batteries, which are 12 A-h) has 432 W-Hr of battery.

So, the Genesis has practically double the battery capacity.

But, the Cuda range at 150ft/min is spec'ed at 5.6 miles and the Genesis is spec'ed at 8.7 miles.

So, the Genesis has 100% more battery, but only 50% more range (at 150ft/min).

If I have mathed correctly, that means the Cuda is burning 136W for 190 min at 150ft/min. The Genesis is burning 166W for 306 min at 150ft/min. Looking at the Genesis Speed/Power chart in the manual, it looks like 166W could be about right for 150 ft/min.

Is the Cuda motor simply that much (22%) more efficient? Is it the prop or shroud/nozzle?

I'm really kinda surprised that the Cuda can get that much range on such a small set of batteries.

Or is that range spec not apples-to-apples versus the Genesis and the Cuda X really does not demonstrate any more efficiency (at cruise) than the Genesis?


Asides:

The Genesis numbers I quoted are on the 3.1 web page, but they are the same as what was there for the 2.1. I believe the 3.1 is more efficient than the 2.1, so the real 3.1 numbers are probably better. But, probably not 22% better?

Anybody have any real world numbers for what the power consumption is on the Cuda or Genesis at 150 ft/min? Someone with a Sentry on a Genesis maybe could say. I don't know if the Cuda has anything similar that would give you that info.

 

[tbone1004]

That's a loaded question. There is no official test for measuring a DPV's range and the last Tahoe Benchmark was essentially a decade ago and was the least bad thing we had. If you look at the benchmark results you can see the power required for the tech vs. rec configuration with each of those dpv's predecessors to get a general ideal of power required. Your specific configuration, but also your technique is going to have a huge affect on power required to move you at 150fpm in the water. Put me in a 3mm, LP72, and no wing with a lot of experience on the trigger and move me at 150fpm is going to be VERY different than moving you with less trigger time in a drysuit and a rebreather. Very different being quite probably twice the power required. Can see that with EV's these days, compare a Hyundai Ioniq 6 to a Hummer EV, same concept.

Another variable that we don't know though is what the BMS setting is going to be for the actual usable capacity of the batteries so even though we can establish what the rated capacity is, we don't know the usable capacity, @Jon Nellis could have a very conservative cutoff on the battery pack to maximize lifespan of the cells and that could be much higher of a cutoff than DeWalt has on their batteries, he could also set a max charge limit of 90% for the same cell life benefits.

What we do know from the 2011 Tahoe is that both the Cuda and the Genesis needed ~250w to move a tech configured diver at 150fpm and the Genesis could move the single tank diver at around 75% of the power that the Cuda required *though this could have easily been a speed setting on the Cuda since it has gears vs. continuously variable*.


TLDR, I would say that their configurations are different for the cruise range and I wouldn't put any serious thinking into one being that much more efficient than the other.

 

[Whitrzac]

It depends on what type of ESC they have as well. The newer FOC/signwave drive esc in the bt/cudax is quite a bit more efficiant than the older square wave ones.

I'm pulling numbers from my butt, but I would guestimate 10-15% more range based on a friends sierra.

 

[stuartv]

That's a loaded question. There is no official test for measuring a DPV's range and the last Tahoe Benchmark was essentially a decade ago and was the least bad thing we had. If you look at the benchmark results you can see the power required for the tech vs. rec configuration with each of those dpv's predecessors to get a general ideal of power required. Your specific configuration, but also your technique is going to have a huge affect on power required to move you at 150fpm in the water. Put me in a 3mm, LP72, and no wing with a lot of experience on the trigger and move me at 150fpm is going to be VERY different than moving you with less trigger time in a drysuit and a rebreather. Very different being quite probably twice the power required. Can see that with EV's these days, compare a Hyundai Ioniq 6 to a Hummer EV, same concept.

Thanks, Tom. I think that info is really what I was looking for. I was really struggling to believe that the Cuda X is THAT much more efficient (if any).

 

[tbone1004]

Thanks, Tom. I think that info is really what I was looking for. I was really struggling to believe that the Cuda X is THAT much more efficient (if any).

to ZJ's point above, the CudaX should be more efficient than the original Cuda's, but you are unlikely to really be near the max range of any of them for a single dive, no different than 8lb scrubbers on rebreathers, it's more about whether it's enough to comfortably do 2 dives on a set

 

[stuartv]

to ZJ's point above, the CudaX should be more efficient than the original Cuda's, but you are unlikely to really be near the max range of any of them for a single dive, no different than 8lb scrubbers on rebreathers, it's more about whether it's enough to comfortably do 2 dives on a set

It's not so much (to ME) about having enough battery for 1 dive specifically. It's about thinking how even better the G3.1 would be if it got 22% more range out of the batteries it already has. But, it sounds like that's not really possible. It's just a pipedream induced by the Cuda X measuring their range differently than how the Genesis range was measured.

 

[lostsheep]

I would really like to see another Tahoe benchmark, I've been bugging some of the folks I know and I there is no shortage of NorCal divers who would donate time and / or their scooters.

@Jona Silverstein ?

 

[Superlyte27]

I would really like to see another Tahoe benchmark, I've been bugging some of the folks I know and I there is no shortage of NorCal divers who would donate time and / or their scooters.

@Jona Silverstein ?

Ask @Jon Nellis about the day the US Navy asked Seacraft, Suex and Genesis to compete for a contract and the results of that competition. It should end the debate on what scooter to buy.

 

[lostsheep]

There's no need, if money was no object then I'd buy Genesis. I've ridden them and I am in NorCal, I support local whenever it's practical. As it is I'll keep riding my old plebeian scooters

 

[tbone1004]

Ask @Jon Nellis about the day the US Navy asked Seacraft, Suex and Genesis to compete for a contract and the results of that competition. It should end the debate on what scooter to buy.

If we ignore the engineering side, since his are the only ones made in the USA it certainly puts him at a huge leg up for a legit contract