Arcona

[Stemar]

Given a decent bit of wind, most modern boats are going to be doing hull speed much of the time, so any extra will be free power. With less wind, you'd have the choice - go faster or slow down a bit and grab some power, but an efficient hull with regen will still be going quicker than an inefficient one without.

It would be getting back to the idea of setting off towards somewhere, and "I think we'll be there before the pubs close", rather than, "We're running late for our restaurant booking, put the engine on" A different kind of sailing.

 

[DJE]

Given a decent bit of wind, most modern boats are going to be doing hull speed much of the time, so any extra will be free power. With less wind, you'd have the choice - go faster or slow down a bit and grab some power, but an efficient hull with regen will still be going quicker than an inefficient one without.

It would be getting back to the idea of setting off towards somewhere, and "I think we'll be there before the pubs close", rather than, "We're running late for our restaurant booking, put the engine on" A different kind of sailing.

"Oh the wind's dropped, never mind we'll eat on board. Put the oven on - oh hang on perhaps we should have thought of that!"




Bottled hydrogen as a cooking fuel anybody?

 

[ProMariner]

It's better to travel hopefully, than to arrive.

 

[Kerenza]

If I could achieve hull speed upwind most of the time I'd have a few more trophies to polish.

 

[lustyd]

could someone explain regeneration returns please?

Going on the data from Uma you'd get ~300W on a retrofit to an old boat and up to 1KW on a modern boat designed with it in mind like the Arcona they tested. You'd get that all day and all night of course if sailing consistently so anywhere from 7KWh to 24KWh per day of free "fuel", more if you have solar. You then have to store it somewhere, but with a diesel engine being upwards of 200KG and having its own dedicated massive cupboard on board, the weight and size of extra batteries isn't an issue. Cost is currently a problem for most, but that cost is dropping on a daily basis as battery production ramps up.

 

[Fr J Hackett]

Going on the data from Uma you'd get ~300W on a retrofit to an old boat and up to 1KW on a modern boat designed with it in mind like the Arcona they tested. You'd get that all day and all night of course if sailing consistently so anywhere from 7KWh to 24KWh per day of free "fuel", more if you have solar. You then have to store it somewhere, but with a diesel engine being upwards of 200KG and having its own dedicated massive cupboard on board, the weight and size of extra batteries isn't an issue. Cost is currently a problem for most, but that cost is dropping on a daily basis as battery production ramps up.

There is a lot of truth in that but UMA generated a maximum of 700W at above 7.5 knots and was hard pressed at lower speeds it was 450 to 500 watts. Vessels that can consistently and comfortably achieve 8 knots or more are bigger and have higher electricity consumption than UMA.

 

[flaming]

Going on the data from Uma you'd get ~300W on a retrofit to an old boat and up to 1KW on a modern boat designed with it in mind like the Arcona they tested. You'd get that all day and all night of course if sailing consistently so anywhere from 7KWh to 24KWh per day of free "fuel", more if you have solar. You then have to store it somewhere, but with a diesel engine being upwards of 200KG and having its own dedicated massive cupboard on board, the weight and size of extra batteries isn't an issue. Cost is currently a problem for most, but that cost is dropping on a daily basis as battery production ramps up.

Yes, and worth saying that sailing boats probably don't need the most expensive energy dense batteries as fitted to cars, as we have comparatively much more available storage space.

There are potentially other advantages, for example it is much easier to provide 2 props set wide in the hull on boats with 2 rudders, and even to have those props retract into the hull for both debris clearing and maximum sailing performance. Obviously 2 props could also give you double the regen if you needed it.

Also worth considering separating the propulsion and generating setups - as this would enable you to have a much more efficient generation propeller, especially at lower speeds.

There is a lot of truth in that but UMA generated a maximum of 700W at above 7.5 knots and was hard pressed at lower speeds it was 450 to 500 watts. Vessels that can consistently and comfortably achieve 8 knots or more are bigger and have higher electricity consumption than UMA.

500 watts is still 12kwh in 24 hours. On long passages that strikes me as being "plenty" for most boats. We don't use that much power in a 4 bed house with electric cooking....
The issue is more the "motor for 2 hours, sail for an hour, then motor for 2 hours" type of deadline driven coastal cruising that many do.

 

[Fr J Hackett]

Yes, and worth saying that sailing boats probably don't need the most expensive energy dense batteries as fitted to cars, as we have comparatively much more available storage space.

There are potentially other advantages, for example it is much easier to provide 2 props set wide in the hull on boats with 2 rudders, and even to have those props retract into the hull for both debris clearing and maximum sailing performance. Obviously 2 props could also give you double the regen if you needed it.

Also worth considering separating the propulsion and generating setups - as this would enable you to have a much more efficient generation propeller, especially at lower speeds.



500 watts is still 12kwh in 24 hours. On long passages that strikes me as being "plenty" for most boats. We don't use that much power in a 4 bed house with electric cooking....
The issue is more the "motor for 2 hours, sail for an hour, then motor for 2 hours" type of deadline driven coastal cruising that many do.

I agree that for offshore cruising boats particularly with the attitude of those sailing UMA then electric propulsion is perfectly possible with a bit of management during low wind speed periods, it was only with the new motor that UMA has been able to be self sustaining but even now it is electrical definite below 5 knot cruising speed. But it is perfectly doable with some load and lifestyle management.

 

[Kerenza]

So so far we have 300w for a loss in speed of say a knot.
An hour of sailing gives us .3kWh and gets me 5 miles. Typical journey could be 50mls of which we can with luck sail 5 hours (1.5kWh) leaving 15 miles to motor having had the tide with us. Of course we are now punching tide, so ground speed is going to be 4knt if we're lucky,, so that's 4 more hours, which I'm not sure we have power for.
The point is not the detail which may or may not be super accurate, but that I couldn't set off with the real possibility of running out of power in the Bristol Channel, with big tides and no where to stop.

 

[lustyd]

Well if you make up numbers to support your position of electric being a bad idea those numbers will, of course, prove it's a bad idea.

People have been sailing the Bristol channel without reliable engines for hundreds of years. It's why Bristol exists.

 

[Kerenza]

But I haven't.

 

[Stemar]

So so far we have 300w for a loss in speed of say a knot.
An hour of sailing gives us .3kWh and gets me 5 miles. Typical journey could be 50mls of which we can with luck sail 5 hours (1.5kWh) leaving 15 miles to motor having had the tide with us. Of course we are now punching tide, so ground speed is going to be 4knt if we're lucky,, so that's 4 more hours, which I'm not sure we have power for.
The point is not the detail which may or may not be super accurate, but that I couldn't set off with the real possibility of running out of power in the Bristol Channel, with big tides and no where to stop.

How did those pilots in their engineless pilot cutters manage out of Bristol? Or the square riggers they were guiding in?

I don't think anyone with any sense is saying that you can do it exactly the same as with a big diesel and bigger tank. Uma's crew adapt the sailing they do to the systems they've got. So do I. With a relatively heavy cat and twin diesels, I couldn't do what they do, and they couldn't do what I do. All the same, I've a sneaking suspicion I know who's getting the better deal - and it isn't me.

 

[Kerenza]

The simple answer is they were doing jt for a living.
As a leisure sailor I am in a different position.
No one wants an electric installation more than me - I have electric bikes, electric outboard, 8kW domestic batteries at home, eNiro on order, the list goes on, but I dont intend to greatly increase my chances of becoming an RNLI statistic until someone can demonstrate to me otherwise.
Without diesel I will have to stop sailing where I do and either give up or move somewhere where I can.

Simply put leisure sailing could be a completely different sport under electrification. My each way bet would be on 48v boats with inverters in 10 years., similar to my home installation.
Unfortunately that infers a whole lot of existing boats are destined for recycling, long before their time.

k

 

[lustyd]

Unfortunately that infers a whole lot of existing boats are destined for recycling, long before their time.

Not really, it suggests that when they are re-engined they will be upgraded to electric. The cost of this is dropping rapidly and the cost of diesel is skyrocketing. It won't be long before the tax dodge is removed either, and then the cost of diesel will have a huge impact on the motor boat fraternity, whether they have a mast/sails on their motor boat or not.

greatly increase my chances of becoming an RNLI statistic

Installing electric won't make you more likely to need a rescue, sailing is still sailing.

 

[Kerenza]

You miss the point entirely. Can't argue a point if you don't acknowledge it.

 

[Concerto]

Installing electric won't make you more likely to need a rescue, sailing is still sailing.

Exactly. Kerenza has not realised the primary "engine" on his boat are his sails. If there is no wind, then an anchor is what is needed. The problem is "sailing" to a timetable. In the past the timetable was never critical as if you missed a tide, then you waited for the next. Improving sailing skills will always reduce the need to use an engine, so make your timetable more flexible and enjoy your sailing by not motoring.

 

[DJE]

Installing electric won't make you more likely to need a rescue, sailing is still sailing.

One of RNLI's current most frequent types of shout is to a sailing vessel with engine failure. I suspect dirty fuel might be replaced by flat batteries as a common reason for needing assistance.

 

[Fr J Hackett]

Exactly. Kerenza has not realised the primary "engine" on his boat are his sails. If there is no wind, then an anchor is what is needed. The problem is "sailing" to a timetable. In the past the timetable was never critical as if you missed a tide, then you waited for the next. Improving sailing skills will always reduce the need to use an engine, so make your timetable more flexible and enjoy your sailing by not motoring.

Doesn't help the time poor cash rich weekend sailors though.

 

[DJE]

I still think that there will be a place in the future for hydrocarbon fuels. But they will have to be produced sustainably. There are huge numbers of chemists working on synthetic photosynthesis and a Swiss university has a pilot plant producing methanol from sunlight and atmospheric CO2. Scaled up 5% of the area of the Sahara Desert it could produce all the world's aviation fuel. See here. I can see the Gulf and African states wanting to get into this in a big way.

Why scrap the whole hydrocarbon infrastructure and embed lots of carbon in the manufacture of replacement motors and batteries?

 

[Fr J Hackett]

I still think that there will be a place in the future for hydrocarbon fuels. But they will have to be produced sustainably. There are huge numbers of chemists working on synthetic photosynthesis and a Swiss university has a pilot plant producing methanol from sunlight and atmospheric CO2. Scaled up 5% of the area of the Sahara Desert it could produce all the world's aviation fuel. See here. I can see the Gulf and African states wanting to get into this in a big way.

Why scrap the whole hydrocarbon infrastructure and embed lots of carbon in the manufacture of replacement motors and batteries?

The Gulf states yes but more likely China with its African investments