Panama Canal on an electric motor

[Dockhead]

Originally Posted by GoneDiving

The OP also has the AC/DC conversion to worry about. A 10kw 48 VDC generator is a rarity and a 10kw AC to DC charger is a substantial charger.

True that. If you're going for a fixed installation, something like this would do it: https://polarpower.com/products/dc-g...rs/8220i-3ca1/


Albeit at a price.

[GoneDiving]

Originally Posted by Dockhead

True that. If you're going for a fixed installation, something like this would do it: https://polarpower.com/products/dc-g...rs/8220i-3ca1/


Albeit at a price.

True. Certainly enough to buy ALOT of diesel or Lithum

[Benz]

When I last transited the canal, I was given to understand by the admeasurer and the pilot that there is no minimum speed: you just have to be honest about your top speed. I told them that I could guarantee four knots with my 8-hp outboard, and they scheduled accordingly.
There are two spots we've anchored in on separate crossings: one at the top of the northern locks (big ship's buoys), and another at Gamboa, just before the skinny bit on the Pacific side. If you can only do 3 kts, I suspect they'd put you through this way, unless they've become more uptight since my last crossing.
What you DON'T want to do is assure them that you can easily do 8 kts and then do only 6. That bums them out.

[belizesailor]

Minimum official speed is 5 knots for a small boat ("handline vessel"). In practice they are not rigorous about enforcing the minimum speed requirements for small boats.


From ACP regulations:

"
d. Speed: The ACP has determined that the minimum full ahead speed required for vessels in order to complete transit in standard times is 8 knots. The Panama Canal Authority shall deny transit if a handline vessel cannot maintain a minimum speed of 5 knots. However, a vessel may be towed through the Canal by another handline vessel if it can tow her at 5 or more knots, or make arrangements to be towed, at their own expense, by a Panama Canal Authority launch. Sailboats cannot transit the Canal under sail. They must transit with motor propulsion. If the vessel is equipped with an outboard motor as its primary propulsion, it must have a means of reversing the engine. The operator must be able to control the outboard motor from the cockpit, or else, the vessel may need a Port Captain’s inspection. Make sure to tell the Canal Inspector the correct top speed that your vessel can sustain. There can be hazardous currents associated with the transit, and it is important that your vessel be able to maintain a safe speed at all times. If, at the beginning of the transit, the craft cannot maintain a safe speed, as reported to the Canal Inspector, the craft will be turned around and returned to the starting point. If this occurs, an aborted transit charge will be billed to the craft and any other related charges.
...
"

[Dockhead]

Originally Posted by belizesailor

Minimum official speed is 5 knots for a small boat ("handline vessel"). In practice they are not rigorous about enforcing the minimum speed requirements for small boats.


From ACP regulations:

"
d. Speed: The ACP has determined that the minimum full ahead speed required for vessels in order to complete transit in standard times is 8 knots. The Panama Canal Authority shall deny transit if a handline vessel cannot maintain a minimum speed of 5 knots. However, a vessel may be towed through the Canal by another handline vessel if it can tow her at 5 or more knots, or make arrangements to be towed, at their own expense, by a Panama Canal Authority launch. Sailboats cannot transit the Canal under sail. They must transit with motor propulsion. If the vessel is equipped with an outboard motor as its primary propulsion, it must have a means of reversing the engine. The operator must be able to control the outboard motor from the cockpit, or else, the vessel may need a Port Captain’s inspection. Make sure to tell the Canal Inspector the correct top speed that your vessel can sustain. There can be hazardous currents associated with the transit, and it is important that your vessel be able to maintain a safe speed at all times. If, at the beginning of the transit, the craft cannot maintain a safe speed, as reported to the Canal Inspector, the craft will be turned around and returned to the starting point. If this occurs, an aborted transit charge will be billed to the craft and any other related charges.
...
"

Another issue here -- 5 knots in WHAT CONDITIONS? Electric boat enthusiasts often like to quote speed in ideal dead calm conditions, and STW. Whereas the Canal Authority is most likely talking about SOG and in whatever conditions there are, which may include headwinds and currents. Need to be really careful about that. Power requirement to maintain a given SOG goes up exponentially with headwinds or currents or both, which is exactly the reason why diesel powered boats generally have a large reserve of power beyond what is required to reach a good cruising speed in ideal conditions.

[belizesailor]

Originally Posted by Dockhead

Another issue here -- 5 knots in WHAT CONDITIONS? Electric boat enthusiasts often like to quote speed in ideal dead calm conditions, and STW. Whereas the Canal Authority is most likely talking about SOG and in whatever conditions there are, which may include headwinds and currents. Need to be really careful about that. Power requirement to maintain a given SOG goes up exponentially with headwinds or currents or both, which is exactly the reason why diesel powered boats generally have a large reserve of power beyond what is required to reach a good cruising speed in ideal conditions.

And there can be considerable current even in the channels, not just the locks...massive volumes of water moving back & forth in the Canal.

I was entering the Atlantic breakwater once after a long sail, fired up the engines, pushed the throttles up to normal cruising RPMs....3 knots...WTF? I thought I must have lost a prop...nope...just strong current exiting the breakwater.

[Benz]

Originally Posted by belizesailor

Minimum official speed is 5 knots for a small boat ("handline vessel"). In practice they are not rigorous about enforcing the minimum speed requirements for small boats.


From ACP regulations:

"
d. Speed: The ACP has determined that the minimum full ahead speed required for vessels in order to complete transit in standard times is 8 knots. The Panama Canal Authority shall deny transit if a handline vessel cannot maintain a minimum speed of 5 knots. However, a vessel may be towed through the Canal by another handline vessel if it can tow her at 5 or more knots, or make arrangements to be towed, at their own expense, by a Panama Canal Authority launch. Sailboats cannot transit the Canal under sail. They must transit with motor propulsion. If the vessel is equipped with an outboard motor as its primary propulsion, it must have a means of reversing the engine. The operator must be able to control the outboard motor from the cockpit, or else, the vessel may need a Port Captain’s inspection. Make sure to tell the Canal Inspector the correct top speed that your vessel can sustain. There can be hazardous currents associated with the transit, and it is important that your vessel be able to maintain a safe speed at all times. If, at the beginning of the transit, the craft cannot maintain a safe speed, as reported to the Canal Inspector, the craft will be turned around and returned to the starting point. If this occurs, an aborted transit charge will be billed to the craft and any other related charges.
...
"

Interesting....this may have been written since my last transit, or else it's just a rule they can enforce if they like. Either way, I told the admeasurer I couldn't guarantee more than four knots, promised to keep things under control, and away we went. My full-keel boat maneuvers very predictably, so we had no issues on that score.

[fourlyons]

Originally Posted by Benz

Interesting....this may have been written since my last transit, or else it's just a rule they can enforce if they like. Either way, I told the admeasurer I couldn't guarantee more than four knots, promised to keep things under control, and away we went. My full-keel boat maneuvers very predictably, so we had no issues on that score.

I don't think so, I transited in 1996 in a 25 foot sailboat with a 7 hp outboard and was asked if I could maintain 5 kn, because it was a requirement. I said yes, only flat out, under ideal conditions. But the advisor said cool, and scheduled us anyway. Sure enough, going west to east we had a stiff headwind and struggled to make 4 knots. Maybe being honest helped.

[valhalla360]

Originally Posted by fourlyons

I don't think so, I transited in 1996 in a 25 foot sailboat with a 7 hp outboard and was asked if I could maintain 5 kn, because it was a requirement. I said yes, only flat out, under ideal conditions. But the advisor said cool, and scheduled us anyway. Sure enough, going west to east we had a stiff headwind and struggled to make 4 knots. Maybe being honest helped.

Are the small boat advisors different from those who handle ships (probably yes) and if they cancel a crossing because they think the boat isn't fast enough, do they lose 2 days pay?

Sounds like playing in a gray area where they might skirt the rules or they might not.

[belizesailor]

Originally Posted by valhalla360

Are the small boat advisors different from those who handle ships (probably yes) and if they cancel a crossing because they think the boat isn't fast enough, do they lose 2 days pay?



Sounds like playing in a gray area where they might skirt the rules or they might not.

Yes, Pilots handle ships, Advisors are for small boats. Note that advisors dont do any actual boat handling, as their title implies: they only advise on operation of the vessel. They are aboard the vessel during its transit.

Advisors are assigned after a boat's transit is scheduled so they would not be involved in the up front evaluation or decision. Likely they would have some role in the decision to abort a transit, but I dont know the details.

[Benz]

Originally Posted by valhalla360

Are the small boat advisors different from those who handle ships (probably yes) and if they cancel a crossing because they think the boat isn't fast enough, do they lose 2 days pay?

Sounds like playing in a gray area where they might skirt the rules or they might not.

Our advisors have always been canal tugboat or crewboat captains picking up extra work. Usually young-ish (sub-35). There's good ones and there's lame ones. They have authority to pull the plug on a crossing, but they don't assess or schedule. One cruiser I heard of offended his advisor and was stuck at anchor in Gamboa for several days, paying extra for time spent, until the Canal authorities relented and sent another to finish his transit.

[fourlyons]

Originally Posted by belizesailor

Yes, Pilots handle ships, Advisors are for small boats. Note that advisors dont do any actual boat handling, as their title implies: they only advise on operation of the vessel. They are aboard the vessel during its transit.

Advisors are assigned after a boat's transit is scheduled so they would not be involved in the up front evaluation or decision. Likely they would have some role in the decision to abort a transit, but I dont know the details.

You're right of course, I remember now it was not the advisor who asked us about our speed, but the official who came aboard to "measure "the boat.

[recollect]

As I understand it if your boat makes less the 7.5kts you will be assigned a 2 day passage, mooring overnight somewhere on Gatun Lake. If the total passage is 43nm lets assume you need at least a 20-25nm range to make it to the mooring on day 1. With the expectation the mooring is somewhere in the middle.

Seems that 5kts is expected. Lets go with that. At 5kts in perfect conditions our electric motor would draw ~110amps or ~5200watts. With at 14kwh battery bank we arent getting far. We could run about 2 hours and make roughly 10nm. We would run out of power half way. Even if we could make it, there is no way to recharge overnight on a mooring ball.


A few options were mentioned and will recap here.

1. Adding a genset. (Seems to make the most sense here. In order to maintain 5kts we would need at least a 6kw genset.)

2. Tow (this would have to be approved ahead of time and cost is unknown at this point)

3. Outboard (must have reverse and cockpit controls)

Thanks again for all the input.

-Dan

[Adelie]

Originally Posted by recollect

Hi Folks,

While we were planning our electric motor conversion the topic came up of transiting the panama canal. From what we have read, sailing is not allowed nor practical. Anyone know of any electric boats that have done it?

Our understanding is that its approx 81nm. We planned on a 48v 300ah LiFepo4 bank or roughly a 14kwh bank. We dont even come close to that range even at 60% hull speed. A small 2kw generator might let us motor at ~3kts but not sure thats fast enough to get though in the allotted time frame nor fight the currents.

Dan

First let me point out there is nothing that says you can't run the electric motor and an outboard at the same time nor that you can't draw from batteries at the same time as you have a generator running.

Having recently looked into converting a Cal 34 I have a sense of how much power is needed to for what speed and what range you can expect.

The vendor I talked with gave me an estimate of 3840w to make 5.0kt. Your boat is longer which helps and heavier which hinders. Let's say it takes an even 5kw for your boat to make 5kt. To account for adverse winds and currents traveling Pac-Atl lets assume you need to 6kw to maintain 5kt over the ground.

Let's say you have a 2kw generator with a charger capable of pushing all of that power into the motor, then you need 3kw from the batteries. That means you can get 4hr or about 20nm out of the batteries before they are down below 20%. From what I can find total transit is 37nm plus some outside of each lock. Lets ignore the distances outside the locks, the generator will be running full blast to top up to batteries while you are in the locks and you will recharge the batteries enough to account for the power needed to between lock and initial or final anchorage.

You can split the transit into 2 days but it's not clear where the midpoint anchorage is, that's something to research. As long as to have a generator and fuel you can run that all night and have the batteries topped up the next morning. The big question is where is the overnight spot. Let's assume the worst and say it's near one of the locks and not half way and you need to make 35nm on a full charge.

To make 35nm on a charge at 5kt you need either 4kw of generator AND charger capacity plus some luck with currents and winds helping you part of the way or you need an outboard.

If you have a 5hp or 6hp (4.0-4.5kw) outboard for the dinghy that you can mount on the mother ship then you need 2kw from the battery or generator to maintain the 5kt.

If you have a 9.9hp outboard motor you can mount then you should be able to maintain 5.5-6.0kt and only use the electric motor maneuvering in the locks when you need quick response.

How big a motor were you looking to mount on your vessel?
Did the vendor give you any info about likely power usage?

[Adelie]

Originally Posted by recollect

As I understand it if your boat makes less the 7.5kts you will be assigned a 2 day passage, mooring overnight somewhere on Gatun Lake. If the total passage is 43nm lets assume you need at least a 20-25nm range to make it to the mooring on day 1. With the expectation the mooring is somewhere in the middle.

Seems that 5kts is expected. Lets go with that. At 5kts in perfect conditions our electric motor would draw ~110amps or ~5200watts. With at 14kwh battery bank we arent getting far. We could run about 2 hours and make roughly 10nm. We would run out of power half way. Even if we could make it, there is no way to recharge overnight on a mooring ball.


A few options were mentioned and will recap here.

1. Adding a genset. (Seems to make the most sense here. In order to maintain 5kts we would need at least a 6kw genset.)

2. Tow (this would have to be approved ahead of time and cost is unknown at this point)

3. Outboard (must have reverse and cockpit controls)

Thanks again for all the input.

-Dan

1. If you are fine drawing the batteries down to 20% then you only need a 2kw generator.

3. If the electric motor is used for maneuvering in the locks then does the outboard still require reverse and cockpit controls since it will only be used for distance motoring?