Electric Boats

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Electric Powered Boats - First Post

Hello all, I'm pleased to see this new category established as we establish a new course towards an all-electric powered vessel. For those who do not know our background, my wife (Maria) and I have enjoyed boating since we met 30+ years ago and enjoyed trawler the past 17 years (3 Nordhavn and 1 Helmsman). We lived aboard (part time) a few years in San Diego, CA and can say those were the best years of our lives. After selling our last trawler and coming to the realization Mary was done boating it was time for me to figure out how I would remain on the water. Thinking small I decided to learn how to sail and after a year of research I commissioned Marshall Marine Corp. to build us a 16' Sandpiper cat style sailboat which we keep in our garage. I selected this style boat for its large beam to length ratio and stability. Recognizing we would likely spend more time harbor cruising than sailing finding the right power source was crucial. For a boat this small we are limited to OB power with a traditional stern mounted OB which IMO takes away from the beautiful lines of the boat. After some research we found another builder who successfully modified the installation of a Torqeedo OB including a side mount (aft) that can easily be removed while sailing. The OB was the same model we had on our 10' Gig Harbor, and we were very impressed with its performance.

After owning the Sandpiper for about eight months it's time to start thinking about our next boat which is likely going to be an all-electric harbor / bay cruiser that can also go outside (weather permitting) and cruise the coastline. While not a true trawler I though starting this thread would be informative for others as we explore where the industry is today and its future. I plan to talk about more than just our boat plans and include other types of boats and related systems which in some cases be relative to trawlers.

Based on what I have read to date on electric power and hybrid electric systems I see successes with smaller boats / systems and believe in time we will see more electric power and systems on trawlers. I hope everyone enjoys following our newest journey and as always, I welcome inputs and comments (positive and negative).

John T. - Nordhavn 4040, 4061, 3522 & Helmsman 38E former owner
Marshal Marine Sandpiper - current owner
 
I have a question and I don’t offer it to be a smart ass. I’m not immune to being a smart ass but I suspect this EV move may fairly soon be nothing more than a fad.

I think it’s assumed that spending one’s money on a boat (or experimental boat) that is electric powered w a motor driven by lithium batteries will be a smart and objective move.

I hear some but less than lots of talk about hydrogen power. Does that include motors? How does hydrogen provide power?

Will hydrogen power take over as a power source in the near future?
Is there anyone here that is on top of the hydrogen power development?
 
I have a question and I don’t offer it to be a smart ass. I’m not immune to being a smart ass but I suspect this EV move may fairly soon be nothing more than a fad.

I think it’s assumed that spending one’s money on a boat (or experimental boat) that is electric powered w a motor driven by lithium batteries will be a smart and objective move.

I hear some but less than lots of talk about hydrogen power. Does that include motors? How does hydrogen provide power?

Will hydrogen power take over as a power source in the near future?
Is there anyone here that is on top of the hydrogen power development?


Hydrogen can be used in 2 ways. You can either burn it in an internal combustion engine, or you can use a hydrogen fuel cell to convert it to electricity.



In general, electric powered equipment is fairly flexible and future-proof (battery related concerns aside), as you can always just produce electricity from a different source and you no longer have to change out all of the equipment to change fuel types.
 
I was going to post these under 'Interesting Boats' in the General Discussion thread, but it seems more appropriate here.

This months issue of Maine Boats Homes & Harbors had an article on Solar Sal Boats, built by Belmont Boat Works in Belfast Maine. These are designed to enable sustained cruising under solar power alone and have extensive photovoltaic panel arrays, unlike some others like Greenline that are hybrid or battery powered where a small set of photovoltaic panels allows for charging the batteries for a more limited range of around 20 miles.

The article reviewed a 24 ft 'picnic' boat, but they have designs for 38 and 45 ft cruisers (by Sam Devlin). It's interesting that these boats resemble the naphtha powered boats of the late 1800's - long and lean, narrow for their length, full displacement, designed to make the most efficient use of very limited power - just like electric boats today. The 38 and 45 also remind me of the Pilgirm 40.

These designs are limited to sustained cruise speeds of around 5 knots in full sunlight. That would be tough in an area with significant adverse currents, or regions that are often cloudy or foggy (like the PNW or Maine). I imagine they would be most useful in places like Florida. I also wonder how many people would buy a 38 ft boat with the interior space of most 28 footers, but slip costs like any other 38 footer. Nonetheless, these designs are beginning to approach the point of feasible cruising under solar power.

https://www.solarsal.solar
 

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While I like the concept of my Trinka 10' dinghy with its Epropulsion outboard and 20 to 25 mile range, I think that is likely about as close as I will get to an electric boat because of my cruising style. Now if I was more likely to cruise from dock to dock (with shore power), I wonder what the feasibility of a cruising boat that you would recharge every night (like an electric forklift) would be. Nothing wrong with capturing some solar power, but I think the market's going to need a 6 or 7 knot cruise with a 40 or 50 mile range to interest cruisers.

Ted
 
While I like the concept of my Trinka 10' dinghy with its Epropulsion outboard and 20 to 25 mile range, I think that is likely about as close as I will get to an electric boat because of my cruising style. Now if I was more likely to cruise from dock to dock (with shore power), I wonder what the feasibility of a cruising boat that you would recharge every night (like an electric forklift) would be. Nothing wrong with capturing some solar power, but I think the market's going to need a 6 or 7 knot cruise with a 40 or 50 mile range to interest cruisers.

Ted

I think you're right (and I too am looking at e-Propulsion for a dinghy). Anything less than a 6-7 knot cruise speed becomes a very limited market, probably restricted to lakes or day 'picnic' boats for a (very) leisurely ride around a sheltered bay.

A 8-9 knot cruise speed plus >100 mile range would start getting my attention. Though, unless it's some kind of ultra-light speciality craft, it doesn't seem possible to achieve that with the current state of the art in a boat that would offer reasonable 'cruising' accommodations. I think the Solar Sal designs by Devlin have pushed the envelope as far as it can go right now (and they look pretty good to me, except for the slow speed).

The laws of physics are very strict. The intensity of sunlight striking the Earth is about 1.4 kW/sq meter. Commercial photovoltaic solar cells are about 15-20% efficient, meaning can extract about 280 watts/sq m. Even 20 sq meters of photovoltaic cells only gives about 5,600 watts to work with. Seems hard to move a conventionally sized and weight boat at reasonable speeds with that.

PV cells will never achieve 100% efficiency, because nothing does. Assuming someday reaching the 50% efficiency some experimental PV cells have shown in lab tests might increase it to 14 kW of power from a 20 sq m PV array. That might be enough to do something reasonable.

But, there are a lot of 'buts.' It might be more feasible in Florida and the Bahamas than PNW or Maine. PV cell output would be greatly reduced in cloudy or foggy conditions (to say nothing of trying to move at night). Batteries would still be needed to store power for those circumstances.

The dream of a pure solar powered boat (or car, or plane) is alluring, but very difficult to achieve in a practical sense. There just isn't enough sunlight falling on the surface area of a vehicle to enable a practical design that could be exclusively powered that way. Compromises are needed (like the Solar Sal Devlin designs).
 
Professional Boat Builder has some recent and very detailed discussions on electric builds for commercial uses. It it worth hunting down the articles.
 
I have a question and I don’t offer it to be a smart ass. I’m not immune to being a smart ass but I suspect this EV move may fairly soon be nothing more than a fad.

I think it’s assumed that spending one’s money on a boat (or experimental boat) that is electric powered w a motor driven by lithium batteries will be a smart and objective move.

I hear some but less than lots of talk about hydrogen power. Does that include motors? How does hydrogen provide power?

Will hydrogen power take over as a power source in the near future?
Is there anyone here that is on top of the hydrogen power development?
As much as internal combustion power is a fad, yes.

Steam was the motive power of choice until internal combustion took over.
IC had many detractors until there were robust power plants and fuel
supplies. It was a new concept that had many negatives the steam didn't.
Couldn't use coal, etc. The new fuels were toxic, expensive and technically
harder to create.

That 'fad' had most of the kinks worked out now as steam had before it.

Electric motive power is already practical for many situations and will only
become more so. Hydrogen still has a long way to go as a widespread fuel
for electric fuel cells but at least it is the most abundant element.
 
We personally aren't there yet, but still in planning for our parallel hybrid with solar assist. No brainer for us, but wouldn't be for everyone.
 

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As much as internal combustion power is a fad, yes.

Steam was the motive power of choice until internal combustion took over.
IC had many detractors until there were robust power plants and fuel
supplies. It was a new concept that had many negatives the steam didn't.
Couldn't use coal, etc. The new fuels were toxic, expensive and technically
harder to create.

That 'fad' had most of the kinks worked out now as steam had before it.

Electric motive power is already practical for many situations and will only
become more so. Hydrogen still has a long way to go as a widespread fuel
for electric fuel cells but at least it is the most abundant element.

Interesting how IC wasn’t very popular early on. “IC had many detractors until there were robust power plants and fuel supplies”. So much like EV today. Gas stations and charging stations. But as an industry gasoline autos was as small as a grain of sand compared to now w the huge infrastructure for gas cars in place.

I’m not a Bill Nye type guy but there must be alternatives. As transportation the gasoline car and boat are still far cheaper. But there’s actually a few used (and thus cheap) EV’s on the market.

Is Carvanna a fad? Re the industry a lot of money is lost at the dealership. I’ve purchased very few new cars but it was nice to be able to return to base even just to ask a question. Perhaps dealerships have been a luxury we just can’t afford anymore?
 
Is Carvanna a fad? Re the industry a lot of money is lost at the dealership. I’ve purchased very few new cars but it was nice to be able to return to base even just to ask a question. Perhaps dealerships have been a luxury we just can’t afford anymore?

Regarding Carvana and dealerships, I never thought they were a luxury, more like a necessary evil. They add cost to the purchase. With today's technology, not sure why they are needed. Most everything else is purchased without going through a salesperson. As far as I know, Tesla has no dealerships. I wouldn't miss them if they disappear, along with real estate agents.

I sold and bought my most recent car through Carvana and thought it was a great experience. They gave me a better than expected trade-in and I ended up with a better used car than any I could find locally though dealerships or private. They showed up at my house, unloaded my car, and loaded up my old one. They handle all the paperwork. Good warranty and protection if you don't like it. Clean Carfax and all maintenance records. No pressure or salesperson to deal with. What's not to love?
 
"but at least it (hydrogen) is the most abundant element"

It is the most abundant element but only because it is combined with oxygen to make water and water is the most common molecule on our planet. There is essentially no free elemental hydrogen in nature to be mined. It all has to be created by man. How?

Hydrogen is used extensively in petrochemical production, but it is made by partially burning natural gas to separate the carbon from the hydrogen atoms. Half of the energy is destroyed in making elemental hydrogen. And guess where the carbon that is separated goes- into the atmosphere as CO2. So much for green.

The only way to make green hydrogen is to use electric power from a green source such as wind, solar, hydroelectric and use an electrolytic process to separate the hydrogen from the oxygen in water. Then it has to be compressed to store and transport and that takes energy.

Compressed hydrogen will see very little use because it is expensive and requires high pressure tanks to store which are bulky. I don't think you will ever see it in cars or boats. At best it might be used as a short-term way to store energy from a solar farm and convert it back to electricity to use at night. And the only way to do that reasonably efficiently is with fuel cells. Burning it in an IC engine/turbine to run a generator is only 30-40% efficient.

So hydrogen is not a source of energy, it is a way to store energy.

David
 
Regarding Carvana and dealerships, I never thought they were a luxury, more like a necessary evil. They add cost to the purchase. With today's technology, not sure why they are needed. Most everything else is purchased without going through a salesperson. As far as I know, Tesla has no dealerships. I wouldn't miss them if they disappear, along with real estate agents.

I sold and bought my most recent car through Carvana and thought it was a great experience. They gave me a better than expected trade-in and I ended up with a better used car than any I could find locally though dealerships or private. They showed up at my house, unloaded my car, and loaded up my old one. They handle all the paperwork. Good warranty and protection if you don't like it. Clean Carfax and all maintenance records. No pressure or salesperson to deal with. What's not to love?

Couldn't imagine buying a vehicle (new or used) without test driving comparable models by different manufacturers to figure out exactly what I wanted. But then I tend to own vehicles longer than most people. I've had 3 vehicles since 1980.

Ted
 
"but at least it (hydrogen) is the most abundant element"

It is the most abundant element but only because it is combined with oxygen to make water and water is the most common molecule on our planet. There is essentially no free elemental hydrogen in nature to be mined. It all has to be created by man. How?

Hydrogen is used extensively in petrochemical production, but it is made by partially burning natural gas to separate the carbon from the hydrogen atoms. Half of the energy is destroyed in making elemental hydrogen. And guess where the carbon that is separated goes- into the atmosphere as CO2. So much for green.

The only way to make green hydrogen is to use electric power from a green source such as wind, solar, hydroelectric and use an electrolytic process to separate the hydrogen from the oxygen in water. Then it has to be compressed to store and transport and that takes energy.

Compressed hydrogen will see very little use because it is expensive and requires high pressure tanks to store which are bulky. I don't think you will ever see it in cars or boats. At best it might be used as a short-term way to store energy from a solar farm and convert it back to electricity to use at night. And the only way to do that reasonably efficiently is with fuel cells. Burning it in an IC engine/turbine to run a generator is only 30-40% efficient.

So hydrogen is not a source of energy, it is a way to store energy.

David
What I mean by H being the most abundant element is that it makes up
74% of the universe with Helium making up about 24% and all the rest of
the elements are essentially impurities. Intended as a 'fun fact'.

You missed my main point in that what seem like major difficulties today
will rather soon become quaint objections once held to be insurmountable.
For example, you don't even mention storing Hydrogen in hydride (solid) form.

Another point worth noting is that burning hydrocarbons is nothing
more than using previously stored energy and thus is part of our
current problem. Renewable production of Hydrogen avoids this.
 
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Couldn't imagine buying a vehicle (new or used) without test driving comparable models by different manufacturers to figure out exactly what I wanted. But then I tend to own vehicles longer than most people. I've had 3 vehicles since 1980.

Ted

That's a fair point Ted. In the case of Carvana, you could (currently) test drive cars from dealers but end up buying from Carvana. In the end, if car dealerships become extinct, I think there would have to be some purchase protection policy. Like most anything else you buy, it should be returnable if not happy with it. Think about things like mattresses, a/v electronics, clothing, etc. We often buy without trying first, knowing that there is low risk if you're not satisfied. Anyone know Tesla's policy?
 
A 8-9 knot cruise speed plus >100 mile range would start getting my attention.
This has been my goal, and I think it can be achieved with sufficient battery. Power density advancements are coming soon. In the meantime, for trawler-sized boats (~40'), it's about 1 kWh/nm at 5 kts. So two Tesla Model 3 battery packs (salvage) at 80 kWh of usable power would get you sixteen hours of 5 kt cruising (80 nm). This, of course, doesn't account for house power or solar inputs.

The laws of physics are very strict. The intensity of sunlight striking the Earth is about 1.4 kW/sq meter.
That's the insolation at Earth's orbit (e.g. what gets to something in space at the distance from the sun that the Earth is). The average insolation on the Earth's surface at MSL is about 700 W/sq m. Solar panel efficiencies are currently (see what I did there? :p) at about 22%, so 154 W/sq m. Daily production, from what I hear, is about 4x the wattage in Wh, so ~600 Wh/sq m.

The dream of a pure solar powered boat (or car, or plane) is alluring, but very difficult to achieve in a practical sense. There just isn't enough sunlight falling on the surface area of a vehicle to enable a practical design that could be exclusively powered that way. Compromises are needed (like the Solar Sal Devlin designs).

It seems the way to deal with this is to go large. Silent Yachts has a line of power cats that are carpeted with solar panels, and in good sunlight can cruise at 5 kts all day. I think the larger boats can cruise at 5 kts for 24 hrs, including providing hotel power. They have a generator for when the battery runs out, but the idea is to not use it.

Electric is the future.
 
Compressed hydrogen will see very little use because it is expensive and requires high pressure tanks to store which are bulky. I don't think you will ever see it in cars or boats.

Both Toyota and Honda make fuel-cell-powered vehicles (FCVs). The Toyota Mirai (https://www.toyota.com/mirai/) is one example. Advancements in battery density and the overall lack of convenient hydrogen refueling stations have made the cars impractical, but there's a good argument for a fuel cell system in marine applications, since there's more space for tankage (long skinny tanks in the little-used bilge areas, for instance). There's a serious advantage in weight reduction, and a relatively small solar-powered hydrogen generator can produce hydrogen from sea water to refresh the system (albeit slowly, and not as efficiently as solar-to-battery).
 
I think when pontiffs talk recently about hydrogen as a fuel, they are referring to recent developments to create a controlled fusion reaction, aka the the same principle as a hydrogen bomb. Solving the problem of controlled fusion would solve a lot of problems.
 
I agree the 100 nm at 8-9 would work. Makes you wonder if that is going to be more achievable with modern sailboats first.
 
"but at least it (hydrogen) is the most abundant element"

So hydrogen is not a source of energy, it is a way to store energy.

David

Exactly. The same can be said about 'electricity.' Electricity is also not a source of energy, but a way to store energy that must be generated by something else. Many fans of battery-electric cars overlook that important detail.

The fact that hydrogen is the most common element in the universe is irrelevant. What matters as far as it being a potential source of energy is availability. How is it produced? As others have pointed out, there is virtually no free hydrogen to be found on Earth because it is so highly chemically reactive. It must be produced, meaning, energy has to be put into a process to separate hydrogen that is chemically bound to something else (such as in water, or oil).

That is one of the problems. The laws of conservation of energy state that a system always has the same amount of energy, unless it's added from the outside. Likewise, energy cannot be created or destroyed, only converted from one form to another. In any conversion process there are inefficiencies (usually energy lost as waste heat). Any energy put into a process to produce hydrogen is going to use more energy than will come out from the resulting hydrogen.

Many fans of electric vehicles also blithely make the throw-away comment "as long as it's generated by green sources." Electricity itself, or hydrogen (or perhaps other storage mechanisms) can all be green if the energy itself was generated by a renewable source (solar, wind, tidal, etc.). But there's the rub, and a non-trivial one. Transitioning the country, and world, to a renewable electric power grid is the crucial first step. But it won't be cheap, or easy.

The fundamental problem is that right now, fossil fuels still provide about 63% of the electricity generated in the U.S., with nuclear an additional 19%. There are significant regional differences, but overall only about 11% of U.S. electric power is generated from renewable sources:

https://www.eia.gov/tools/faqs/faq.php?id=427&t=3

The fundamental need is to change the U.S., and world, electric generating grid to renewable sources. That will take a lot of money. Just for the U.S. it would cost over $5 trillion (let’s assume a nice even $10 trillion with the inefficiencies, corruption, bureaucracy, inflation (that was a 5 year old estimate), inevitable cost overruns, and pork in our system):

https://www.renewableenergyworld.co...lace-where-should-infrastructure-spending-go/

Especially in the new coronavirus reality, with the world likely heading into several years of economic difficulties, and the U.S. having to deal with trillions of dollars already spent on ‘economic recovery’, it’s hard to see where and when the money could come from to convert to renewable sources.

The scientific data on climate change are overwhelming. We need to save our planet and do whatever we can to combat climate change. After all, this is the only planet we have, so not killing it - and ourselves in the process - seems like a really good idea. The horrific forest fires on the west coast of the past few years are yet another example of what we will have more of in the future if we don’t do something. Even the lobsters are leaving New England and moving north to Canada to escape rising ocean water temperatures. But going 'electric' alone does not solve anything as long as the primary energy source used to generate that electricity wasn't renewable.
 
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Electric still holds some advantages even with fossil fuel sourced electricity. Large scale generation is typically more efficient than small scale. And you can seamlessly swap out the generation source without impacting the end user equipment (which allows for continuous improvement).
 
Thanks for informative post Nick and I agree with most of what you say. Some would argue that forest fires are not the result of climate change. That aside, the problem I have is that in the US, we angst over this issue a lot, but don't acknowledge it's a global problem. The US is very clean in producing fuel and electricity, but much of the world is not. Furthermore, our attack on fossil fuels does not take a global view. For instance, rather than producing fuel in a clean manner in the US, we'd prefer to buy from other coutries that are not nearly as clean. Rather than move oil through a pipeline very cleanly and efficiently, we'd rather move it by boat, truck, or rail. Much of the fuel produced in the world, is spent by transporting that fuel. I'm not arguing against addressing climate change, I just wish we could do it in a non-political and global manner.
 
Thanks for informative post Nick and I agree with most of what you say. Some would argue that forest fires are not the result of climate change. That aside, the problem I have is that in the US, we angst over this issue a lot, but don't acknowledge it's a global problem. The US is very clean in producing fuel and electricity, but much of the world is not. Furthermore, our attack on fossil fuels does not take a global view. For instance, rather than producing fuel in a clean manner in the US, we'd prefer to buy from other coutries that are not nearly as clean. Rather than move oil through a pipeline very cleanly and efficiently, we'd rather move it by boat, truck, or rail. Much of the fuel produced in the world, is spent by transporting that fuel. I'm not arguing against addressing climate change, I just wish we could do it in a non-political and global manner.

Thank you. You make a very important point: it's a global problem that needs a global solution. We can wring our hands and be sanctimonious here in the U.S., but even if we somehow snapped our fingers and came up with $10 trillion and converted our electric grid to green renewables, while it would help, it would definitely not solve the global problem.

China currently gets 60% of its electricity from fossil fuel, mostly coal. Japan is building 22 new coal powered electric generating plants, which together will release about as much CO2 as all the cars sold in the U.S.:

https://www.nytimes.com/2020/02/03/climate/japan-coal-fukushima.html

The war in Ukraine is making things even more difficult, as countries bring coal plants back on line in response to embargoes and cut-offs of oil and gas from Russia.

https://www.cnbc.com/2022/06/21/ukr...-to-coal-as-russia-squeezes-gas-supplies.html

There's also the still unsolved problem of storing the electricity made from renewable sources. Solar is (of course) only generated when the sun is shining. At night, or under cloudy conditions, not so much. Wind can blow at any time - and can stop at any time. There is not yet an effective means of storing large amounts of electricity produced by a renewable source, so that it could be released at night or when the wind isn't blowing.

'Batteries' are not the answer. Lithium is too expensive, and there isn't enough supply to go around and make enough batteries to store and supply electricity on a national (or global) level (even if one ignores that much of it comes from child slave labor in despotic countries).

https://www.power-eng.com/energy-storage/implications-of-a-lithium-ion-storage-transformation/

https://www.nature.com/articles/s41467-020-18402-y

https://www.technologyreview.com/20...-cant-rely-on-batteries-to-clean-up-the-grid/

https://www.theguardian.com/environ...s-the-price-we-could-pay-for-a-greener-future

You're absolutely right that we need an integrated, global solution. But we can't even unify this country. With the war in Ukraine now one more thing driving wedges between countries and further polarizing us, it's hard to see how a global response will happen anytime in the foreseeable future.
 
I think when pontiffs talk recently about hydrogen as a fuel, they are referring to recent developments to create a controlled fusion reaction, aka the the same principle as a hydrogen bomb. Solving the problem of controlled fusion would solve a lot of problems.

IMO, the Pope should stay in his own lane!
 
Just curious Nick, and you probably know more than me, but why are we not embracing more nuclear power? Obviously there is the waste disposal issue, but are there other reasons? Seems like a clean solution to me.
 
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