Has any harbour ever offered shore-power to swinging moorings?

Greenheart

Greenheart

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Considering the durability of seabed cables, and the fact that anchoring isn't usually permitted amongst moorings, is there any good reason why a weatherproof shore-power connection couldn't be provided to boats lying well away from the shore?

Wouldn't mooring-landlords enjoy a substantial new portion of the berthing market, if yachtsmen who would really prefer a quiet spot, but who require the consistency of shore-power for on-board systems, could have both?
 
Not sure how it would cope if the boat were to rotate a few times rather than simply swinging backwards and forwards in opposing directions. Swivels on moorings are standard, swivels on 240v in seawater could be pricy!
 
Assuming your post is serious, the number one good reason is the complete and utter mis match between AC current, presumably at 240volts, and highly conductive seawater. Any substantial distribution system would require a 3 phase supply with neutral so the actual phase to phase potential would be 415volts.

How would you provide a guaranteed 100% waterproof, and indeed to IP68, termination where you would connect on to the supply ? Such a connection would have also to be completely dry at the point of making electrical contact, and 100% guaranteed that under no circumstances could a short to the seawater ever occur.

IMHO this would never ever be possible.
 
No, I wasn't kidding - just deeply electrically ignorant. I'd no idea it was that impossible. Thanks for explaining.

Just the same...since most essential yacht systems run on lower voltages, mightn't there be a safe option to supply fewer than 240 volts? The cigar-lighter outlet in SWMBO's little Micra has enough power at 12v to run a laptop or lamp through a small 240v inverter...enough power in 12volt-form to be useful, but not a deadly current, surely? Granted it wouldn't be shore-power as we know it, but it might keep a small well-insulated fridge cool.

Regarding the rotating mooring, is that really beyond the wit of science? In Australia I had a hoover whose supply-cable could be twisted an infinite number of times - the connection was always consistent.
 
telephone cables were/are? run to mooring buoys, but that was normally when two buoys are /were used front[bow] and back[stern] They didn't have high voltage though
 
dancrane said:
No, I wasn't kidding - just deeply electrically ignorant. I'd no idea it was that impossible. Thanks for explaining.

Just the same...since most essential yacht systems run on lower voltages, mightn't there be a safe option to supply fewer than 240 volts? The cigar-lighter outlet in SWMBO's little Micra has enough power at 12v to run a laptop or lamp through a small 240v inverter...enough power in 12volt-form to be useful, but not a deadly current, surely? Granted it wouldn't be shore-power as we know it, but it might keep a small well-insulated fridge cool.

Regarding the rotating mooring, is that really beyond the wit of science? In Australia I had a hoover whose supply-cable could be twisted an infinite number of times - the connection was always consistent.
Click to expand...
The problem with a low voltage supply would be cable losses reducing the voltage to an unusable level. Sorry IMO just wouldn't be practical.

I will PM you some useful reading.
 
It is an interesting challenge to provide power at an acceptable cost. Certainly much easier with a trot mooring than a swing mooring. To use a lower voltage means less total power available in practice. So a few amps at 12v would be much easier than 13 amps at 240v AC. Especially when it comes to a swivelling electrical connection.
However at our club marina most people like the jetty (pen) concept for step aboard convenience and only a fraction of users use shore power continuously.
Certainly solar is cheaper more convenient for a swing mooring than the cable concept.good luck olewill
 
dancrane said:
Considering the durability of seabed cables, and the fact that anchoring isn't usually permitted amongst moorings, is there any good reason why a weatherproof shore-power connection couldn't be provided to boats lying well away from the shore?

Wouldn't mooring-landlords enjoy a substantial new portion of the berthing market, if yachtsmen who would really prefer a quiet spot, but who require the consistency of shore-power for on-board systems, could have both?
Click to expand...
power is distributed over reasonable distances in high voltages/low currents because it lightens the wires. less cross sectional area for the power, and less voltage loss.
That sort of voltage is infeasible in a sea water environment (lethal).

Safer, lower voltages imply higher currents and fatter wires, with higher proportionate losses per foot of length.
This is an issue up/down the mast, let alone from shore to mooring!

Then there is the issue of the connection mechanism. The provider cannot assume the user will keep the supply dry, so It has to be seriously waterproof, which is unlikely.

Then there is the swing aspect, preventing the wire from twisting around the mooring.

All told, not a feasibility imho.
 
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dancrane said:
Regarding the rotating mooring, is that really beyond the wit of science? In Australia I had a hoover whose supply-cable could be twisted an infinite number of times - the connection was always consistent.
Click to expand...

Did it also carry the weight of the hoover and sit in seawater?

Does this power connection also have to serve as a mooring? If not it would get tangled up!
 
However, let's not give up entirely on this concept. Here in New Zealand, a couple of scientists have just won a large amount of grant money as the Prime Minister's science Prize for research on the transmission of electrical power from one electrical circuit to a separate non-connected circuit by induction loops. Apparently, there are huge implications for the future - envisaged was a series of such loops embedded in roads, along which suitably-equipped electric cars could travel, picking up a brief charge as they passed over each loop.

with this in mind, not too difficult to envisage an induction loop being built into, say the concrete top of a mooring block, powered from the shore. No moving parts and well below the surface, so not too much of a problem to waterproof it. Next, the moored boat lowers down the mooring cable another induction loop connected to its own electrical system, to rest above, or on top of the mooring block and pick up power from it. As the boat rotates around the mooring cable, so will the loop, but it will still pick up power. Again, apart from the movement of the upper loop on the block, no moving parts, so no problems to waterproof it.

Not to say that I would feel the need to ever use such a system, but it's a hypothetical approach that might work with a bit of design input.
 
They could maybe help us by letting us moor to some of the offshore wind farms. Surely they could spare a few amps.

But do they link to shore at ultra high voltage to reduce loss? Oh... and they can twizzle round on the end of their stick, so it must be possible.

(For clarity - I'm not serious.)
 
Fossil said:
...suitably-equipped electric cars could travel, picking up a brief charge as they passed over each loop...not too difficult to envisage an induction loop being built into, say the concrete top of a mooring block, powered from the shore...
Click to expand...

You had me, till you mentioned the mooring loop. I thought the whole idea was feasible, but transferring 240 volts through live parts so close to the water, sounds slightly "Jackass".

I still have a gleam of hope that a way could be found, but such high voltage in a frequently-drenching environment sounds more than challenging.
 
It would be easy to supply trots:
Armoured cable
Decent plug and socket, eg not Wickes commandos.
Supply at 110, to make handling the socket much safer.
Step up transformer on yacht to 230v.

We would have a couple of bits of kit to buy, and a couple more safety drills to observe.
But lots of people wouldn't mind that.
110ac is standard for building sites, shipyards etc because it is far safer.
I think it's a great idea!
anyway dangling a 230v household extension lead in the water doesn't seem to have any effect, have a look around your marina and you will see it in action!
 
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jerrytug said:
110ac is standard for building sites, shipyards etc because it is far safer...I think it's a great idea!
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Thanks Jerry. It occurred to me that people with on-board fridges/freezers etc, presently have no option but to berth in marinas or shut their boats down during long absences...

...so even if the kit required to enable safe 'powered moorings' was expensive, it'd probably be any amount cheaper than marina fees. Plus, not everybody likes marinas.
 
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