Lagoon 420 hybrid + modern tech

[ranchero76]

I don't think we'll see solar panels with 30% or more efficiency anytime soon in real life. So the only available options for now - adapt design (of boat) to solar panels, dropping price on solar panels as technology improves (and I think this will continue), and improving power management of each panel, allowing partial shading without dramatic reducing of whole panel output (that's very important when installed on sailboat, for example).

[valhalla360]

Originally Posted by Stumble

As everyone knows I am a huge critic of solar powered boats, but there is absolutly no question that solar panels make sense from an ecological standpoint. The energy payback period on commercial cells is at worst about three years, better cells are as low as nine months.

Batteries obviously don't produce power, but allow you to time shift it, and by delaying or reducing the amount of diesel use during have a major ecological benefit. I just can't find data on how many kWh of power it takes to produce on battery so I can't make a reasonable guess on their effect. But my feeling is that over the lifecycle of a FLA offset diesel usage more than offsets their logistical and production overhead.

There are plenty of good arguments against solar boats, but this isn't one of them.

Obviously but my comment was trying to figure out what a certain poster is trying to accomplish. One thought was range to cross oceans under power.

Obviously, it makes more sense to use the sails with a modest solar system to handle house loads.

That poster has since said eco is not his goal but its still unclear what he is trying to accomplish.

[a64pilot]

Originally Posted by valhalla360

Obviously, it makes more sense to use the sails with a modest solar system to handle house loads.

That poster has since said eco is not his goal but its still unclear what he is trying to accomplish.

Sails I believe remain to be the most cost effective, efficient way to cross oceans and I think the smallest impact on the ecology.

If being an Eco warrior is your goal, and I admire that if it's real.
But my opinion the best way to go about that is to rescue and old, good boat and keep it out of the land fill, then rehab it with used parts when possible and go sailing with as you said a modest solar array.
You may can have a smaller footprint living in the wilds of Alaska in a log cabin, but not by a whole lot I wouldn't think.

Now I truly admit I'm in it for the comfort mostly, but I don't mind making decisions that are ecologically sound, sort of icing on the cake.

[valhalla360]

Originally Posted by a64pilot

Sails I believe remain to be the most cost effective, efficient way to cross oceans and I think the smallest impact on the ecology.

If being an Eco warrior is your goal, and I admire that if it's real.
But my opinion the best way to go about that is to rescue and old, good boat and keep it out of the land fill, then rehab it with used parts when possible and go sailing with as you said a modest solar array.
You may can have a smaller footprint living in the wilds of Alaska in a log cabin, but not by a whole lot I wouldn't think.

Now I truly admit I'm in it for the comfort mostly, but I don't mind making decisions that are ecologically sound, sort of icing on the cake.

Please don't call me an Eco-warrior. Most I've found are idiots who either don't understand the issues or could care less about the actual impacts because they have a "cause" to support.

I try to make smart choices. Example: I drive a V10 F250 but I'll bet I use less fuel than 9 out of 10 Prius eco-warriors because I've chosen a lifestyle that doesn't require me to commute 40-60miles per day. (I also use it's truck capabilities for a significant percentage of the miles.)

Take away the Eco-warrior factor an no one has come up with a viable justification for a hybrid powered boat.

[a64pilot]

I wasn't actually calling anyone an Eco warrior, however I see nothing wrong with the concept, although I do have an opinion that many self proclaimed Eco warriors are not.
Al Gore maybe being the King of the fake ones, yes he irritates me.
However if we are to get onto to the Eco warrior band wagon, the way to make that a success is to make it viable and economically smart. Your Prius example, even though you meant it as a negative I'll accept that is was due to your not knowing any better. Our primary vehicle is a Prius, and yes until last week I had a C3500 Dually Diesel truck too, cause the Prius can't do everything. However the Prius will do anything any other car its size can do, causes zero lifestyle changes, you don't have to plug it in, it has unlimited range, has all the acceleration, load carrying ability and top speed of any other vehicle of its size and type, lasts just as long or longer, it just burns half the fuel and much less emissions, and about half the total operating expense. Just wish there was a Miata or Lotus version of the thing, then it would be perfect .

But there is a viable Hybrid boat, has been for a very long time, it's a Diesel sailboat, that is as hybrid as hybrid gets isn't it?

[valhalla360]

Originally Posted by a64pilot

I wasn't actually calling anyone an Eco warrior, however I see nothing wrong with the concept, although I do have an opinion that many self proclaimed Eco warriors are not.
Al Gore maybe being the King of the fake ones, yes he irritates me.
However if we are to get onto to the Eco warrior band wagon, the way to make that a success is to make it viable and economically smart. Your Prius example, even though you meant it as a negative I'll accept that is was due to your not knowing any better. Our primary vehicle is a Prius, and yes until last week I had a C3500 Dually Diesel truck too, cause the Prius can't do everything. However the Prius will do anything any other car its size can do, causes zero lifestyle changes, you don't have to plug it in, it has unlimited range, has all the acceleration, load carrying ability and top speed of any other vehicle of its size and type, lasts just as long or longer, it just burns half the fuel and much less emissions, and about half the total operating expense. Just wish there was a Miata or Lotus version of the thing, then it would be perfect .

But there is a viable Hybrid boat, has been for a very long time, it's a Diesel sailboat, that is as hybrid as hybrid gets isn't it?

No objection to someone driving a prius. If it fits your use pattern, it's a fine option. They just get a bad rap because they are the eco-warrior car of choice.

The reason I came to the conclusion I use less gas is I've actually had one of the sanctimonious eco-warriors berate me in a parking lot for driving my F250. When I quizzed him it turns out he chooses to live 50miles from work, so he actually burns more fuel per year than I do.

Of course around 30% of miles I'm hauling stuff or towing way more than a prius could handle and we've limited ourselves to a single car, so not really an option. (Back when work had me on the road doing 30,000miles per year, I had a compact car because it made sense)

[PacificGreen]

https://www.youtube.com/watch?v=QqbTOLoItnk

https://www.youtube.com/channel/UC6B...cixqeoS1XlLYww
Youtube channel for more vidoes.

Generators can supply the propulsion and house loads at up to 100 48v DC amps 6kw. The longest sea trials are 17nm so far. Can cruise for extended periods. Upriver against 1-3 knots of current for extended periods and still maintain 3.5-4knots. Solar energy helps to off set propulsion expenditures from the bank.

You can see in the videos the solar power is quite cable of making a normal usage case of 5-25 amps so anywhere from 250-1500 watts of power. This is enough to propel the vessel via solar alone.

Solar Catamaran 8Meter.
Twin 4kw Rayeo Electric Outboards.
2160w solar. 79.60 voc 32.88 amp
400amp hour Winston Lithium Batteries 16 in series at 48v nominal.
Displacement 5600 lbs.
Two AlphaGen DCX3000 3kwh DC Generators.
Electric Incinolet head
Induction Cooktops
Two Quick 16 Boilers
Pressurized Water
Washing Machine
Toaster Oven
Fridge
Heaters
Dehumidifiers
70 Gallon Water Storage
Atmospheric Water Maker
2 3000w 48v inverters.
2 48v Shore chargers provide 30amps

Sea Trials.
Hull Speed 6.7 knots Large thrust, max power 7500 watts.

Cruise Speed 4 knots low energy 10-15 amps sun dependent. 500 to 1500 watts.

Ultra Cruise 3 knots and below gives more range.

There really is no point going faster than 4 knots with this Catamaran. Optimum speed is reached very easily with low energy use 40 amps to motors - 20 amps from sun = cruising for 20 amps at 1000-1100 watts.

All ahead full yields an energy draw of 150 amps that can be sustained for 2.7 hours from batteries alone. Hull speed is achieved at around >100amps. This can be buffered easily from internal combustion DC Generators that are load bearing and can produce 100 amps for as long as the fuel is present and voltage below 52.5 volts. Generators easily keep batteries happy. Solar takes care of the rest.

Winston 400ah cells have over 400amp hours in the bank as these cells clock in at around 425ah each.

Catamaran has not been optimized for weight, weight placement regarding generators tools in the cockpit. Propellers are 12 1/2" x 10" weedless propeller not optimized, trim not optimized.

Adding 36v xi5 gps trolling motor for anchoring. Boat has 4 anchors already included in displacement with chain and rode. Trolling motor will utilize 36v 72ah calb cells and charger to maintain gps anchor during night. 72ah calb cells included in initial displacement as backup 48v bank 16 in series. Trolling motor functions as secondary propulsion and secondary or primary autopilot in conjunction to Lowrance cable steer outboard pilot.

[downunder]

Boy o boy those are head-spinning videos.

[PacificGreen]

Yeah they are not great for sure. Was the end of six month outfitting, launching, with schedules, constraints. Limited time for sea trials. Gratifying, challenging and at times rushed.

[valhalla360]

Originally Posted by PacificGreen

There really is no point going faster than 4 knots with this Catamaran. Optimum speed is reached very easily with low energy use 40 amps to motors - 20 amps from sun = cruising for 20 amps at 1000-1100 watts.

As has been said repeatedly, if you are willing to accept drastically reduced performance, it's viable.

For a 8m catamaran, hull speed should be north of 7-8kts, so your cruise speed is roughly 50% of hull speed. Most people want a cruise speed capability of 80-90% of hull speed. Most people would argue there is a point in going faster than 4kts.

Also, while interesting, scaling this up to a 14 meter boat isn't going to add 80% to the energy consumption but several times as much power. This is supported by the stunt boats record breaking crossing barely beating your little home built system.

A viable option might be to scale it down to a 4m boat to use as a dingy. If you are less than a 1/4mile to the dingy dock, 4kts would be acceptable for many, especially since many anchorages are no-wake zones. Even if it's a mile or two, drawing down the batteries doing 6kts could be acceptable if the boat will sit for a few hours refilling the batteries. With minimal need to accommodations and storage, you could keep it really light and use really slim hulls reducing power demands and increase speed.

[valhalla360]

New idea: Solar Dingy

Take a pair of hobbie cat hulls mount to a platform with 5' beam.

Using a 12v trolling motor pullng 40a with a 200ah battery.

Assuming 50% discharge limit, that gives you a 2.5hr maximum range.

Mount a 200w solar panel for charging as part of a bimini that folds down when not in use. That should generate around 67ah or around 1.5hr range (assuming 4hr output and some losses).

A 1.5hr range at say 5kts, should give you around 8 round trips to a dingy dock 1/2 mile away and you have enough range for rare unusual conditions.

In a pinch, you could hook the battery up to shore power or the mother ship (assuming it has a generator) if you need a boost.

[PacificGreen]

Originally Posted by valhalla360

As has been said repeatedly, if you are willing to accept drastically reduced performance, it's viable.

Hard to see siting there becalmed in the middle of the bay with no wind any better - now that's a performance hit if your willing to accept that it too is viable.

Originally Posted by valhalla360

For a 8m catamaran, hull speed should be north of 7-8kts, so your cruise speed is roughly 50% of hull speed. Most people want a cruise speed capability of 80-90% of hull speed. Most people would argue there is a point in going faster than 4kts.

Hull speed for this catamaran is 6.7 knots on 25.5' Lwl so my hull speed should be just south of 6.7 knots. So my cruise speed is roughly 50% of hull speed which is 3.38 knots. 80% of my hull speed is 5.4 knots and indeed I can cruise at that to if I choose. Most people would argue there is a point in going faster than 1kts.

Originally Posted by valhalla360

Also, while interesting, scaling this up to a 14 meter boat isn't going to add 80% to the energy consumption but several times as much power. This is supported by the stunt boats record breaking crossing barely beating your little home built system.

I never mentioned anything about scaling anything up and I'm not sure what you refer to as a stunt boat. If your talking about the world renowned Sun 21 then I'm more than sure if they used flexible solar panels and a decent lithium bank they would have had a much easier time of it considering their system would have weighed less for the panels and the batteries.

The power to weight ratio would have been even less with their existing 16kw of motor power so they would probably turn prop for less amps all day long while going slightly faster because of less weight perhaps even approaching their theoretical hull speed 9.08 knots when wanted but who would want to go fast on a solar boat just doesn't make any sense especially when Sun 21 and mine are not designed to go fast.

Originally Posted by valhalla360

A viable option might be to scale it down to a 4m boat to use as a dingy. If you are less than a 1/4mile to the dingy dock, 4kts would be acceptable for many, especially since many anchorages are no-wake zones. Even if it's a mile or two, drawing down the batteries doing 6kts could be acceptable if the boat will sit for a few hours refilling the batteries. With minimal need to accommodations and storage, you could keep it really light and use really slim hulls reducing power demands and increase speed.

A viable option might not have been to scale it down to a 4m boat to use as a dingy. You would then have no room for accomodations, fridges, water heaters, electric incinerating toilets, boilers, ovens, washing machines or the like.

When a 1/4mile away from a dingy dock or 14 mile from a dingy dock didn't seem to matter if it was a tug on the river or a waving bystander on the dock there was certainly a wake. Even at a 20 miles doing 6kts burning 90amps - 20 coming in from sun=70amps into 400amp hour would take me 5.7 hours at that speed at which time I'd start the generators and carry on. What is it with your need for speed? Most sailboats will hardly ever see over 8knots anyhow and if they are going faster than that they eventually trim down anyhow to something more comfortable and reasonable that is not as hard on their sailing gear.

Not quite sure why you would want a boat with no accommodations or storage. I have a an electric dingy if you bothered to visit my channel you would see. The CraigCat with a ray 48v and 72ah batteries and generator plus 2 adults probably weighed around 750lbs. We could cruise all day on that 72ah bank and do laps around the lakes all day.

[PacificGreen]

Originally Posted by valhalla360

New idea: Solar Dingy

Hmm, people have been doing this for years already so it is certainly not a new idea.

Originally Posted by valhalla360

Take a pair of hobbie cat hulls mount to a platform with 5' beam.

An nice 12' inflatable hull usually works just as well. No need to go wrecking a perfectly good Bill O'Brein Hobbie cat. Bill designed and built my boat too in 1964.

Originally Posted by valhalla360

Using a 12v trolling motor pullng 40a with a 200ah battery.

Not sure if your clear on the concept of a throttle at all and how power curves work in relation to electric boats. They are very efficient at lower speeds and if the operators choose they can even go faster with them but yes at the expense of their battery.

Originally Posted by valhalla360

Assuming 50% discharge limit, that gives you a 2.5hr maximum range.

Why would you assume the worst case of lead is dead mentality. Lithium batteries are everywhere. 4 200 ah lithium cells rigged for 12v would weigh 31.6 pounds. They can be discharged to 80%. You could turn prop on that boat for 5 amps and go for 32 hours. Conversely you could choose to go 10 amps for 16 hours, 15 amps for 10.7 hours, 20 amps for 8 hours, 25 amps for 6.5 hours, 30 amps for 5.3 hours or 40 amps for 4 hours.

Originally Posted by valhalla360

Mount a 200w solar panel for charging as part of a bimini that folds down when not in use. That should generate around 67ah or around 1.5hr range (assuming 4hr output and some losses).

Actually that would be a great idea. With 200w at 12v that would give 5.4 amps extra that get absorbed instantly into the batteries or used for propulsion. So for as long as the sun shines you could pretty much cruise around for free to the extent of the solar input. Plenty of people doing that already with or without lithium batteries.

Originally Posted by valhalla360

A 1.5hr range at say 5kts, should give you around 8 round trips to a dingy dock 1/2 mile away and you have enough range for rare unusual conditions.

More like if you rigged as I described you would not ever have to worry about range anxiety. Nobody with an electric boat is going to want to go 5kts unless they really need to because they understand the principle behind it especially if they have to make 8 round trips to the dingy dock and back to the boat for a 1 mile rounder. But then lets do the math on that so 8nm is easily done 8x60/5 knots=96 minutes. Well within the constraint of even a lead acid powered dingy doing 5knots.

Originally Posted by valhalla360

In a pinch, you could hook the battery up to shore power or the mother ship (assuming it has a generator) if you need a boost.

If running an electric dingy and the solar is behind then it is a good idea to charge it up from either shore power or from the mother ship with either generator, solar panels, PEM fuel cell or wind generator.

[valhalla360]

Originally Posted by PacificGreen

Hard to see siting there becalmed in the middle of the bay with no wind any better - now that's a performance hit if your willing to accept that it too is viable.

Of course not, that's why it is exceedingly rare to find engineless sailboats.

Hull speed for this catamaran is 6.7 knots on 25.5' Lwl so my hull speed should be just south of 6.7 knots. So my cruise speed is roughly 50% of hull speed which is 3.38 knots. 80% of my hull speed is 5.4 knots and indeed I can cruise at that to if I choose. Most people would argue there is a point in going faster than 1kts.

Odd, the standard calculation suggests a bit over 7kts and cats usually beat the standard calculation due to the narrow beam/length ratio. But if we accept your value, your suggested cruise speed of 4kts is still far below 80% of hull speed. Your average cruising boat with BELOW average size fuel tank can run at 80-90% of hull speed for at least 8-10hrs and most can do 24hrs or more.

I never mentioned anything about scaling anything up and I'm not sure what you refer to as a stunt boat. If your talking about the world renowned Sun 21 then I'm more than sure if they used flexible solar panels and a decent lithium bank they would have had a much easier time of it considering their system would have weighed less for the panels and the batteries.

Check the title of the thread. It's about a Lagoon 420, so if we want to extrapolate from your experience we need to scale it up. As far as your speculation regarding the "world renowned" Sun21, if it was so easy, why didn't they do it? This wasn't so long ago that the technology wasn't available. There has been no huge technological leap forward to suggest a different outcome.

The power to weight ratio would have been even less with their existing 16kw of motor power so they would probably turn prop for less amps all day long while going slightly faster because of less weight perhaps even approaching their theoretical hull speed 9.08 knots when wanted but who would want to go fast on a solar boat just doesn't make any sense especially when Sun 21 and mine are not designed to go fast.

Huh? They were trying for the record speed for a crossing? If they could gotten anywhere close to a 9kt average speed, we'd be seeing a market shift replacing sailboats with solar powered boats because they can match or exceed sailboats and sun is more reliable than wind (fyi: their hull speed is probably closer to 12-15kts given the long narrow hulls)

A viable option might not have been to scale it down to a 4m boat to use as a dingy. You would then have no room for accomodations, fridges, water heaters, electric incinerating toilets, boilers, ovens, washing machines or the like.

What dingy has fridges, water heaters, toilets, washing machines etc..? I was pointing out an alternate use for the technology that is viable and for certain users, may even be cost effective. For pretty close to the price of a 2-4hp outboard (as most won't plane anyway), I could put together the solar powered system. There would be a convenience factor in that most users (how many really go back and forth 6-10times a day) would never need to worry about fuel and maintenance would be negligible. You just get in, throttle forward and go.

em to matter if it was a tug on the river or a waving bystander on the dock there was certainly a wake. Even at a 20 miles doing 6kts burning 90amps - 20 coming in from sun=70amps into 400amp hour would take me 5.7 hours at that speed at which time I'd start the generators and carry on. What is it with your need for speed? Most sailboats will hardly ever see over 8knots anyhow and if they are going faster than that they eventually trim down anyhow to something more comfortable and reasonable that is not as hard on their sailing gear.

Most cruising sailboats run in the 5-8kt range (larger generally being faster). The exception being people just out for a day sail willing to drift along at 2-3kt. Go down to the ICW or other popular cruising route and watch. You will almost never see a boat going from point A to B doing less than 5kts.

probably weighed around 750lbs. We could cruise all day on that 72ah bank and do laps around the lakes all day.

Sure you can cruise a very long TIME if you don't want to cover a lot of DISTANCE. Set the engine so it's just barely moving and you get a long duration. Bass boats with trolling motors do this all the time. They just need a little thrust to maneuver the boat but when they want to get 5-10miles back to the dock, they crank up the big engine.

[valhalla360]

Originally Posted by PacificGreen

Hmm, people have been doing this for years already so it is certainly not a new idea.

Trolling motors yes. With solar I've never seen one in real life. Without the solar, it's a hassle to either move the batteries to the mother ship or you have wires hanging off the stern. Plus the mother ship needs enough power to keep up with the extra load anyway.

An nice 12' inflatable hull usually works just as well. No need to go wrecking a perfectly good Bill O'Brein Hobbie cat. Bill designed and built my boat too in 1964.

If you poke around on craigslist, you can find old hulls for next to nothing but they would be relatively easy to build similar hulls.

The problem with an inflatable, is the ones I've seen with trolling motors top out around 3kts and the ones with 4hp gas engines leave a huge wake if you use the available power and get up to 6-7kts. A hobbie hull (or similar) can do those speeds while leaving negligible wakes.

Not sure if your clear on the concept of a throttle at all and how power curves work in relation to electric boats. They are very efficient at lower speeds and if the operators choose they can even go faster with them but yes at the expense of their battery.

Understand it completely. That's why it's not a viable option on large cruising boats. You have to accept a major downgrade in performance. On a 40 mile day, what should take maybe 7hrs for a normal cruiser becomes 10hrs at 4kts. Late fall heading down the ICW, that may mean running out of daylight or if caught on a large bay in a storm, you are exposed for longer.

On the other hand for a dingy there is little, if any, speed difference and even if there was on a 1/4 mile run it couldn't add up to more than a minute or so (most of which would be made up by not having to start the gas engine) so there isn't much impact on the user.

Why would you assume the worst case of lead is dead mentality. Lithium batteries are everywhere. 4 200 ah lithium cells rigged for 12v would weigh 31.6 pounds. They can be discharged to 80%. You could turn prop on that boat for 5 amps and go for 32 hours. Conversely you could choose to go 10 amps for 16 hours, 15 amps for 10.7 hours, 20 amps for 8 hours, 25 amps for 6.5 hours, 30 amps for 5.3 hours or 40 amps for 4 hours.

Because we want this cost effective. Li is getting closer but is still much more expensive. Yes, Li is viable if you want to go that route.

Actually that would be a great idea. With 200w at 12v that would give 5.4 amps extra that get absorbed instantly into the batteries or used for propulsion. So for as long as the sun shines you could pretty much cruise around for free to the extent of the solar input. Plenty of people doing that already with or without lithium batteries.

Agreed, it was a quick 10min idea. But I've yet to see anyone doing it in real life. Also, the total AH output of the panels won't change much, so your available per day AH isn't really impacted. It would only be if you only use the dingy every other day that you could take advantage by starting with a 100% battery and also using the immediate solar output to increase your range but then the next day, you would have reduced range if the battery wasn't 100% before the sun sets.

More like if you rigged as I described you would not ever have to worry about range anxiety. Nobody with an electric boat is going to want to go 5kts unless they really need to because they understand the principle behind it especially if they have to make 8 round trips to the dingy dock and back to the boat for a 1 mile rounder. But then lets do the math on that so 8nm is easily done 8x60/5 knots=96 minutes. Well within the constraint of even a lead acid powered dingy doing 5knots.

Range issues would not be an issue with a dingy use case unless you wanted double digit planning speeds. It's very viable using tried and true technology because a dingy use case rarely includes miles or hours of motoring. It's the same as electric cars. They are a great option as a 2nd car for commuting but horrible for a cross country trip (because people aren't going to accept a speed limit of 40mph to increase range because that's all someone decided they really need)

If running an electric dingy and the solar is behind then it is a good idea to charge it up from either shore power or from the mother ship with either generator, solar panels, PEM fuel cell or wind generator.

I see almost the same problems with electric boat proponents that I see with electric car promotion. The people pushing it are trying to say it's just as capable as the standard option but anyone with a brain can see that there are major drawbacks. BUT (AND IT'S A BIG BUT), if you pick a use case that is common and target that market, it could be very successful. We could have 10-20% electric cars on the road by now if they had focused during the high fuel prices on marketing electric cars with 50-60mile range to families with multiple cars and sold it as a commuter car. That's a common use case (commuting under 50miles roundtrip) and they typically have a garage with a power outlet. They have a full function vehicle if they want to do a longer road trip anyway. With the lower range, they could have cut the cost so it would be competitively priced (before subsidy) with your standard econobox. They would have sold like hotcakes. Instead, they get lumped in as crackpot ideas because they refuse to acknowledge their limitations (ie: claiming it's "range anxiety" as if the buyer is just a silly fool is actually insulting the buyer rather than admitting it has limited range and is really best suited to commuting.)