ghostlymoron
Well-Known Member
I dont think they've got enough space for 10x but could easily double their solar I'd think. If they intend to stop in the UK for long, I'd think they will add some.
Electric drive, Sailing Uma
- Thread starter ghostlymoron
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ryanroberts
Well-Known Member
He was just chilling, using the dock wifi.
Stemar
Well-Known Member
This is a canal boat, but it's the sort of thing I'd like on my bespoke boat.
I've often thought that, were I silly rich, I'd have something like a Southerly, and replace some of the weight in the ballast plate with batteries to drive an azipod ahead of each rudder, using a diesel generator to charge them when the solar panels can't keep up, which I fully accept would be much of the time. One advantage of such an arrangement would be the ability to position the motor anywhere in the boat, including transversely.
I've often thought that, were I silly rich, I'd have something like a Southerly, and replace some of the weight in the ballast plate with batteries to drive an azipod ahead of each rudder, using a diesel generator to charge them when the solar panels can't keep up, which I fully accept would be much of the time. One advantage of such an arrangement would be the ability to position the motor anywhere in the boat, including transversely.
JumbleDuck
Well-Known Member
A chap I know spent a lot of time converting his Victoria 800 (8m) to electric drive. Once he had the propellor sorted it was very impressive, and he had a range of about 10 miles on a locker full of lithium-ion batteries. Since all he wanted was something to get him in and out of harbour plus an occasional boost round a headland, that suited him fine, and he could keep up 2-3kt indefinitely with a suitcase generator running.
The downside was the cost, £20k for the original install, which had lead-acid batteries, and the lithums would have cost the same again if one of the big electrical equipment manufacturers hadn't got interested and supplied the batteries in exchange for performance data.
I reckon hybrid is going to be the way to go. Instead of having a 30hp (say) engine which is rarely needed, boats will carry a 15hp engine for extended motoring and 15hp of electrical for getting in and out of harbour silently or for augmenting the diesel when more oomph is needed.
The downside was the cost, £20k for the original install, which had lead-acid batteries, and the lithums would have cost the same again if one of the big electrical equipment manufacturers hadn't got interested and supplied the batteries in exchange for performance data.
I reckon hybrid is going to be the way to go. Instead of having a 30hp (say) engine which is rarely needed, boats will carry a 15hp engine for extended motoring and 15hp of electrical for getting in and out of harbour silently or for augmenting the diesel when more oomph is needed.
LONG_KEELER
Well-Known Member
I happened to weigh a 110Ah battery the other day . It weighed 23.5 kilos. Almost as much as my 6hp 4 stroke outboard. Three or four of those would probably spoil the performance of a smallish yacht. Probably, the only way is lithium.
dunedin
Well-Known Member
In one of their articles they state that they have never had to run the motor for more than 30 minutes (so a range used of 2-3 miles only). This reflects the very different nature of ocean crossing without any deadlines vs many coastal cruisers.
Sailing Uma— WHY ELECTRIC
northwind
Well-Known Member
At the moment, energy density is the biggest issue for Solar, compared to using dinosaur poo, its about 40 times less.. Range anxiety is a big concern and not having the ability to replace that used energy in a self sufficient way is always going to make people nervous, which is why hybrid is really the only sensible option at the moment.
Nigel Calder has a much more measured approach to Electric drive on a sailboat, than the edited dreams of Youtubers... The Science of Hybrid Propulsion: Part 1
Nigel Calder has a much more measured approach to Electric drive on a sailboat, than the edited dreams of Youtubers... The Science of Hybrid Propulsion: Part 1
ghostlymoron
Well-Known Member
Nigel Calder's article needs an executive summary before I get much enlightenment from it.
I have the same doubts about marine hybrids as I do on cars - all the energy comes from fossil fuel - so it's hard to see how the electric motor is an advantage. The Uma crew only use solar (which Calder ignores) which changes everything. It all depends on your type of sailing. Atlantic crossing in a yacht is 2000nm of sailing with say 1 hour of motoring each end. A hurried weekend cruise could be a day sailing then a day motoring back to be home in time for work. Two extremes. For retired folk the pressure to be back for work disappears and you can change plans/destinations to accommodate lack of wind (or surplus thereof) and be more flexible. So electric power suits some and not others. But it has many advantages - no or little maintenance, no smell, no noise and if you're somewhere sunny, you can replenish your batteries from solar so cheap running as well.
Daverw
Well-Known Member
I did see one episode where they had to run the outboard on the tender alongside, i think this was due to lack of time to charge and they needed to get going.
Red Panda
Well-Known Member
If my trusty little diesel ever dies, it's getting replaced with an electric motor. There are an increasing number of commercial electric drive solutions for sailing boats, and battery technology improves almost by the month.
I'm lucky in that I have a boat that sails well even in light winds, and I mostly control my own deadlines, but I encounter a lot of motorboats with sails out there.
I'm lucky in that I have a boat that sails well even in light winds, and I mostly control my own deadlines, but I encounter a lot of motorboats with sails out there.
Buck Turgidson
Well-Known Member
if you're not time limited then great, fill your boots. I would do as someone else suggested and mod a boat with internal ballast swapping lead for lead acid and saving the thousands that lithium costs for more solar. However, as I sail in my spare time it's not a risk I can take right now.
LittleSister
Well-Known Member
Charlie Stock managed coastal sailing without any engine for decades, travelling mostly at weekends (having to be back to work Monday) and covering much greater distance than most of us, and IIRC only failed to get back to his mooring once.
I think it takes mainly a different attitude to most of us, together with good navigation and planning skills.
I think it takes mainly a different attitude to most of us, together with good navigation and planning skills.
rotrax
Well-Known Member
Or you have made the decision to travel somewhere on your boat and you do it.
First Mate and I are travelers by water. If the wind will not serve, up goes the Iron Jib.
I know several club members who use your methods. One couple waited five weeks to go across and down channel. We were on our way back by the time they got there.
We do, of course, take advantage of favourable tides, but headwinds are not a stopper unless severe.
lw395
Well-Known Member
Do they still use hydrocarbons for cooking?
ghostlymoron
Well-Known Member
I've seen them using a microwave
scruff
Well-Known Member
certainly Delos has gone over to solar + electric cooking. It worked for them in the tropics, will be interesting to see if it works when they get to Svalbard...
I think we can all appreciate the technology for solar + electric drive is not quite there for northern latitude recreational (weekends + a fortnight holiday per year) boat owners. However solar tech is moving at pace now - a few years ago a 20w panel would be well over £100. Now you can get 200w for similar money so 10x cheaper.
Couple that with the work that's going on prototyping solar panels woven into sails at the moment and good things could be happening. I recon in a decade or so we will likely find solar and battery proving all auxiliary power for propulsion, cooking and driven boats are a genuine feasible option.
I think we can all appreciate the technology for solar + electric drive is not quite there for northern latitude recreational (weekends + a fortnight holiday per year) boat owners. However solar tech is moving at pace now - a few years ago a 20w panel would be well over £100. Now you can get 200w for similar money so 10x cheaper.
Couple that with the work that's going on prototyping solar panels woven into sails at the moment and good things could be happening. I recon in a decade or so we will likely find solar and battery proving all auxiliary power for propulsion, cooking and driven boats are a genuine feasible option.
lw395
Well-Known Member
There are certain fundamentals which go beyond a matter of mere technology.
There is 1kW per sq m or so of solar energy of which it's quite hard to harvest more than say 1/4.
Then you have cloud, rain and fog.
You can either angle your sails to work with the wind or the sun. If you want both at once, that's your heading defined?
It is very easy to run a boat on 100% wind and biofuel, you can run a diesel engine on natural oils, you can cook with the same, or you could use bioethanol for either heating, propulsion or both. I can't see that attracting much of a Youtube following though.
xyachtdave
Well-Known Member
No worries, you motor wherever you want to.
Adjusting my plans to suit the weather suits me.
Zing
Well-Known Member
Here's another calculation to put things into perspective.If you cover your boat in solar panels you might, if very lucky have 10 sq m of area available for solar panels, so 2kw of capacity and 10Kwh of power harvested on a good day. Deduct a little for lights etc. That is about the same power at the prop as 3lts of diesel will produce. If that's all the diesel you had in your tank you would not be happy. It won't catch on.
rszemeti
Well-Known Member
The range figures earlier sound correct .. 12kWh giving 10 hours at 3 knots ... so 12 kwh giving 30 nautical miles range ... lets say 36 nm and then its a neat 3 nautical miles per kwh ... so one 110Ah lead-acid battery might get you 2 miles?
Possibly in the Caribean ... but try that in Anglesey and you will probably be eating cold food quite quickly. You cannot get out more than you put in, and only so much light falls on a vessel ... even if you could capture it all, in the UK out of season, it is not a lot. Boats are already pretty efficient in the water, they are not going to improve significantly ... electric motors are very efficient in converting energy into motion .. there are simply no more significant gains to be made in that department. It is probable that solar energy capture ratios will improve, but you cannot capture what is not there ...
For the type of sailing I do, where a strong motor is my "safety net", electric is a LONG way off being practical, and I suspect in these Northern cliamtes may never be practical simply because of the lack of energy arriving from the sun.
Possibly in the Caribean ... but try that in Anglesey and you will probably be eating cold food quite quickly. You cannot get out more than you put in, and only so much light falls on a vessel ... even if you could capture it all, in the UK out of season, it is not a lot. Boats are already pretty efficient in the water, they are not going to improve significantly ... electric motors are very efficient in converting energy into motion .. there are simply no more significant gains to be made in that department. It is probable that solar energy capture ratios will improve, but you cannot capture what is not there ...
For the type of sailing I do, where a strong motor is my "safety net", electric is a LONG way off being practical, and I suspect in these Northern cliamtes may never be practical simply because of the lack of energy arriving from the sun.