Oceanvolt Hybrid Motor

[valhalla360]

Originally Posted by BigBeakie

Re suitability of a good EP solution for cruising, let's briefly summarise what has been shown with OV systems in operation and validated by owners:

1. An OV motor can propel a performance cruising catamaran at close to, i.e. within one or two knots, the same top speed as a diesel engine about twice the kW rating. Not at exactly the SAME top speed, but close.
It sounds like you are playing with the idea of hull speed and how power needs to go slightly faster are drastically higher as you get in the vicinity of hull speed. If the current spec diesel pushes a boat to a hair past hull speed and you want to spec a boat that does 1kt below hull speed, you could drop the hp/kw by half for either the electric or the diesel and achieve the same thing. The electric HP is not more powerful than the diesel HP, you are just setting a lower bar for the electric HP and then claiming false equivilency.

2. The OV motors can deliver reasonable cruising speeds, i.e. 6 to 7 knots, for these cats using 7 to 8 kW of battery from suitable C rated LFP batteries, and this can be continuous motoring if a suitable genset is used to deliver the 7 to 8 kW needed.
We can't say this unless you give us specific information about the boat. It might for some boats and fail on other boats. If you are talking about a high performance light weight boat not facing stiff headwinds or waves, it might be possible but that same boat is likely capable of 30-50% higher speeds typical diesels...but again, we can't say for certain without more info.

3. For most motoring needs less than about 1 hour at top speed, or several hours at less than top speed, solar charging of the LFP bank would provide most of the energy required, until the next motoring event is repeated. Over a longer timeframe of cruising, solar can provide almost all the fuel required. The opex of this fact is a compromise that cruisers with diesel engines need to accept, and pay for, over and over again.
Again without knowing more about the boats and what your definition of "top speed", "less than top speed", size of the solar and LFP bank is, we can't say that. We also can't say a diesel option will be paid for "over and over". It may be so much cheaper up front that a lifetime of diesel fuel is already paid for in savings compared to the electric option.

This ignores if 1hr at "top speed" is really acceptable to the buyer.

4. OV Servoprop regeneration is capable, at typical sailing speeds of these cats, to provide as much charging as a medium size genset, without slowing down the cat significantly, i.e. more than 1 knot.
Again, it depends greatly on the boat and on the assumed conditions. If you have a boat pushing up against hull speed and has to shorten sail, it's possible to lose little or nothing in terms of speed while generating decent power output. In more modest conditions, it's much more questionable assumption and modest conditions tend to be more common.

So, to me, it appears the compromise, singular, you have to live with re EP is motoring at a slightly lower top speed for MUCH less time than running on diesel engines at WOT. If that is the major compromise of EP, I'm certainly willing to accept that compromise.

Of course, if it's a true sailing machine as implied that can and will be sailed in virtually all conditions, any fuel savings is negligible and you could probably get away with a couple of 5hp diesels running thru big reduction gear boxes just for maneuvering in harbor with just a 5 gal tank and it will be drastically cheaper up front and eliminate 99% of fossil fuel consumption. With no need for electric propulsion, the solar and battery bank eliminate the need for using the props for power generation.

[DotDun]

Originally Posted by BigBeakie

2. The OV motors can deliver reasonable cruising speeds, i.e. 6 to 7 knots, for these cats using 7 to 8 kW of battery from suitable C rated LFP batteries, and this can be continuous motoring if a suitable genset is used to deliver the 7 to 8 kW needed.

FWIW, while totally becalmed yesterday, I was doing 5kts at 2000rpm (both engines) which on the propeller power curve from Yanmar equates to ~4kW per engine. As I stated before I get 7-7.5kts at 2700rpm (both engines) which is ~9kW per engine.

Hence your lighter boat may do 6+kts in totally calm conditions using 8kW. BTW, I find becalmed is a rare occurrence.

Of course, the Yanmar stated output mentioned above is the maximum the engine will produce at that rpm. Since the throttle mechanism 'requests' an rpm, it's up to the governor to deliver that rpm, up to the capabilities of the engine. Point being, actual kW used to move the boat at any rpm can be less than stated on the curve. The only way to really know is perform precise fuel flow measurements.

[SDChristian]

Originally Posted by Mark424

I'd tweak your approach.
(1) Diesel Saildrive in one hull w/ serial generator/motor between diesel and saildrive.
(2) (optionally) drop the 2nd generator, and have electric drive in the second hull. Batteries to suit needs, maybe carbon foam instead of LiFePo, (or buy a tesla power wall 2 Much cheaper per KWH.)

For low power/short time period, you can still run electric only w/ both props.

For long distance you'll need a generator running in your scheme, so just use one diesel+saildrive and save the conversion inefficiencies and extra cost. You can generate extra power if you need it w/ the serial gen on the flywheel. A larger main diesel/gen will be much less weight than a small + medium sized one. One set of controls, exhaust, cooling system, etc. Monos have been cruising for ever w/ a single diesel, they are reliable.

For motor sailing, when the batteries are full, shut down the diesel and use the electric on the other hull for the assist.

You just described this exact system: http://www.hybrid-marine.co.uk/resou...lel-Serial.png

[BigBeakie]

We tried to go with Hybrid Marine, but lost all confidence he could actually deliver and then support after sales. He also had only very limited options on engines, and no solution using Beta Marines latest engine designs such as their excellent 45HP Turbo.


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[SDChristian]

Originally Posted by BigBeakie

We tried to go with Hybrid Marine, but lost all confidence he could actually deliver and then support after sales. He also had only very limited options on engines, and no solution using Beta Marines latest engine designs such as their excellent 45HP Turbo.


Sent from my iPad using Cruisers Sailing Forum

Interesting, considering I called them once and they seemed very uninterested in new business. My conclusion after that call was that they make all their money on commercial canal vessels that can operate mostly on an all night dockside charge each night.


I still like the concept if someone can execute properly.

[BigBeakie]

Yes, I agree. He has good Powerpoint slides though😀

In fairness, we had no doubts about Graeme re his technical expertise or the quality of what he had based on the Beta50, but it just didn't seem like he would put the effort into a solution for us. So we had to consider the longer term financial viability of his operation, and Oceanvolt was a better solution anyway.


Sent from my iPad using Cruisers Sailing Forum

[transmitterdan]

There is another hypothesis to consider. Maybe he is a good business operator focused on a market where EP makes good sense for both customer and supplier. There seem to be more than one bankrupt EP company that was over exposed to the cruising market. I think any good EP provider could find many other customers better suited to EP than cruisers.

[valhalla360]

Originally Posted by transmitterdan

There is another hypothesis to consider. Maybe he is a good business operator focused on a market where EP makes good sense for both customer and supplier. There seem to be more than one bankrupt EP company that was over exposed to the cruising market. I think any good EP provider could find many other customers better suited to EP than cruisers.

Ironic on another thread, I said, canal boats would be an excellent use case for EV. They apparently beat me to it. With many canals being restricted to low speeds, short daily distances and overnight charging with shore power, it's far more viable for a typical buyer.

Given that they are putting reasonable HP in their examples and gave an example of a fairly typical cruising boat that showed above 4.5kts, a straight diesel engine if most efficent and didn't try to claim magic HP...I'm far more willing to trust these guys. I could nitpick some of the comparisons they did but they openly admit the issues with their tests.

Not sure if they build a good product and I would be a little nervous that most of the documents are 10yrs old but at least they are matching the technology to an appropriate use and not claiming magical abilities.

[Stumble]

Originally Posted by valhalla360

Ironic on another thread, I said, canal boats would be an excellent use case for EV. They apparently beat me to it. With many canals being restricted to low speeds, short daily distances and overnight charging with shore power, it's far more viable for a typical buyer.

Given that they are putting reasonable HP in their examples and gave an example of a fairly typical cruising boat that showed above 4.5kts, a straight diesel engine if most efficent and didn't try to claim magic HP...I'm far more willing to trust these guys. I could nitpick some of the comparisons they did but they openly admit the issues with their tests.

Not sure if they build a good product and I would be a little nervous that most of the documents are 10yrs old but at least they are matching the technology to an appropriate use and not claiming magical abilities.

The one issue with canal boats is that if they are used a lot shore power may not be enough to replace the charge used in a day. A typical 50amp shore power cord can provide a maximum of 50*110=5.5kwh of power an hour. Even assuming 100% charging efficiency and 16 hours of charge time a day that is still only 88kwh of available power a day, or about 11kw/hr used on the motors. But that also is assuming you use no additional power at night to run a fridge, turn on lights, AC, etc.

It is just doable, but you would probably need to invest in a second shore power line and system to be comfortable.

[PaulinOz]

Originally Posted by Stumble

The one issue with canal boats is that if they are used a lot shore power may not be enough to replace the charge used in a day. A typical 50amp shore power cord can provide a maximum of 50*110=5.5kwh of power an hour. Even assuming 100% charging efficiency and 16 hours of charge time a day that is still only 88kwh of available power a day, or about 11kw/hr used on the motors. But that also is assuming you use no additional power at night to run a fridge, turn on lights, AC, etc.

It is just doable, but you would probably need to invest in a second shore power line and system to be comfortable.

Remember only about 20% of the world uses 110 volts AC the rest of us all have access to 220/240 Volt AC. But still probably does not change the thrust of what you are saying.

[Jim Cate]

Hmm...

f
For me in my limited time cruising the French canals, the real joy was just pulling over to the bank and driving some stakes in for mooring... out in the woop-woop. Obviously. no shore power there. And in the few marinas that we stayed in, either no power or limited 240 volt... no five kw hookups in sight.

So, the recharging issue is alive and well IMO, even in those low challenge waters.

Jim

[valhalla360]

Originally Posted by Stumble

The one issue with canal boats is that if they are used a lot shore power may not be enough to replace the charge used in a day. A typical 50amp shore power cord can provide a maximum of 50*110=5.5kwh of power an hour. Even assuming 100% charging efficiency and 16 hours of charge time a day that is still only 88kwh of available power a day, or about 11kw/hr used on the motors. But that also is assuming you use no additional power at night to run a fridge, turn on lights, AC, etc.

It is just doable, but you would probably need to invest in a second shore power line and system to be comfortable.

Having a small backup generator is probably in order but let's take your numbers.

Canals are often no wake zones with 4-5mph speed limits. So 10kw is probably enough for typical conditions (maybe even a little bit high). Assuming you do a 5hr run, that means you only need to replace 50kwh.

On top of that, if the 5hr run includes a couple of locks at 30min each, you really are only using 10kw for 4 hours (in the lock the engine is off) so you are down to 40kwh used.

A narrowboat is probably worst case for solar but assuming a 60' canal boat has 40'x6' available for solar at 15w per sf, that's 3600w of solar which if you can stay out of the shade might generate a little less than 15kw per day...Let's round down to 10kw to account for shade and some cloud cover. A wider boat, could probably carry more.

That means you need to pull 30kwh from shore power. To do that on 120v power over a 16hr stop, you need to pull about 15amps for propulsion charging.

Also, this assumes you travel every day. Travel every other day and the solar will generate roughly twice the amount (20kw) and shore power only needs to provide 20kwh over 40hrs which is 5amps at 120v.

Reduce the travel days a bit or stay 3-4days and full solar is even possible.

Again what entices me about the idea is this is a use case where the technology matches what typical users do. It doesn't ask the user to change to match what the technology can do.

[valhalla360]

Originally Posted by Jim Cate

Hmm...

f
For me in my limited time cruising the French canals, the real joy was just pulling over to the bank and driving some stakes in for mooring... out in the woop-woop. Obviously. no shore power there. And in the few marinas that we stayed in, either no power or limited 240 volt... no five kw hookups in sight.

So, the recharging issue is alive and well IMO, even in those low challenge waters.

Jim

I was thinking of the Erie Canal where every small town has converted the old commercial dock into free dockage for pleasure boaters and most have shore power. They really don't pull up to the shore to tie off along most of the route.

But see my previous response. Assuming it's a leisurely trip (which is common for those wandering canals), solar is viable for most or all of the travel. I was probably overstating the demand with 10kw. 5-8kw will probably get you 4mph. Biggest issue would be shade.

[ejlindahl]

We only have diesel propulsion on our canal boat but regarding EP in Holland. Most places we stay at are the town moorages. The circuit breakers on their shore power stations are typically 4 or 6 amps at 220V. If you try and pull more than that the breaker will trip. More expensive private marinas may have bigger breakers but we don't stay in those. They are all metered so you pay for what you use. IIRC it is one Euro per KW so there is that expense. Next year we will be in France so we will see what the going rate for electricity is there.

The Netherlands is well on their way to generating all their electric power from wind and solar. Additionally I think it was National Geographic that had an article that stated that they are the second largest exporter of food in the world, second only to the USA. Amazing for such a small country with such crappy weather.

[valhalla360]

Originally Posted by ejlindahl

We only have diesel propulsion on our canal boat but regarding EP in Holland. Most places we stay at are the town moorages. The circuit breakers on their shore power stations are typically 4 or 6 amps at 220V. If you try and pull more than that the breaker will trip. More expensive private marinas may have bigger breakers but we don't stay in those. They are all metered so you pay for what you use. IIRC it is one Euro per KW so there is that expense. Next year we will be in France so we will see what the going rate for electricity is there.

The Netherlands is well on their way to generating all their electric power from wind and solar. Additionally I think it was National Geographic that had an article that stated that they are the second largest exporter of food in the world, second only to the USA. Amazing for such a small country with such crappy weather.

As shown in my figures, that would still be enough power to work on a leisurely canal cruise. (5amp 240v is roughly equal to 10amp 120v) So it's not a technological problem.

WOW...the cost of that great free green energy is enough to make you long for a good old fashion coal powered steam engine.

Then again solar starts to become viable given the limited power demands. Maybe a small generator as backup if you need to cover significant miles in a day.