When a Tesla trawler?

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We'll see a Tesla car in space before we ever see a Tesla trawler.
 
"D" politicians are trying their best to drive you out of petroleum-powered vehicles. In California: electric-car purchases are subsidized, given the privilege to drive on highways on reserved high-occupancy lanes, and exempt from paying for maintaining the roads.
 
Mark, I can't tell whether the 'D' in #63 is directed at mine in #23, but: I think there are some basic facts in our energy use that need to be dealt with.

1, Our national security depends upon our having fuels/energy sources and chemical feedstocks to meet our needs. (Though never spoken about by our leaders, our national security depends upon our having the people and means of manufacture to meet our needs.) 2, Some fuel and feedstock sourcing despoils our land during, and forever after, extraction. 3, Changes in technology of use and extraction are forever changing the economic and environmental equations favoring their use. 4, Entrenched and wealthy participants in fossil fuel and feedstock businesses are powerful defenders of their turf.

My opinions (for all their extreme value and brilliance): 1 & 2, We need to ensure our national security by (amongst others): developing, securing and not wasting or despoiling our natural resources of fuels, lands and people. 3, We need to develop and exploit new technologies. 4, The oligarchs (oily-garchs?) need to become part of the long-term solution, rather than remain the near-term profiteers.

Therefore (I continue to blather): Some government intervention/encouragement for new technologies and currently-available technologies is important. (Though I really wonder about government programs enabling friends who've 'bought' a Volt for 2/3 of sticker price.) Fossil hydrocarbons are too valuable, in the long run, to burn. Electrical power systems, with today's technology, can't function once the non-fuel sources become too much of the supply; witness Germany. Today's battery technology depends on minerals not available in the US and other energy storage schemes are nowhere near enough (pumped water, compressed air, etc.). And not to mention the ever-worsening environmental cost of carrying on as we are.
 
Let me first say that I have nothing against electric anything, or alternative anything. I actually have an off-grid solar house, and an all electric (not a Tesla) car. This is just a factual look at the state of the technology with respect to application in a trawler.

Here are some reasons why you won't see battery electric power in a recreational trawler for a long, long time. The issue is less about comparing electric motors to diesel motors, and more about comparing energy stored and carried as diesel fuel vs charge in batteries. Here's why:

- 100 gal of diesel occupies 13 cu ft, and contains 1490 KWh of usable propulsion power after accounting for the burn efficiency of the diesel engine. And at a dock fill rate of 15 gpm, it takes about 7 minutes to refill.

- To store and carry the same amount of usable energy using LiFePO4 batteries which are the current state of the art, occupies 460 cu ft (35 times more space), and using a 50A/240V shore power connection takes 5.75 days to recharge (1250 times longer). The batteries would cost $745,000. Even at an optimistic life span of 3000 cycles, that's a lifetime battery cost of $248 per cycle, or the equivalent of $2.48/ gal of fuel. And that's just the cost of the batteries and does not include the cost of the electricity to charge them each time.

And I think most of us would find a total of 100 gal of fuel pretty limiting. If you go to 500 gal of diesel, you need 2300 cu ft of battery space. That's pretty much the entire interior volume of a 30' boat. And your battery bank now costs $3.7m
 
The oligarchs (oily-garchs?) need to become part of the long-term solution, rather than remain the near-term profiteers.

Well, here is my blather.

The ultimate profiteer in this discussion is none other than Elon Musk. I see where the American taxpayer is on the hook for the failed SpaceX fiasco.

Don't get me wrong, P. T. Barnum stories are great, real and entrepeunership at its best. PayPal anyone?

Since we are not short of petroleum based fossil fuels (ps, nuclear fuel is fossil too) and have centuries in front of us with current technology, making them evil sells well. Being labeled evil opens up new opportunities for the hucksters, politicians and creative likes off Elon Musk, Al Gore, Jimmy Carter and Chinese windmill suppliers.

When will birth control ever become a way to reduce our reliance on fossil fuels? Likely never as it diminishes the tax base and doesn't get politicians elected. Nor does it appeal to mass marketing 101.

:hide:
 
Let me first say <snip>

That may or may not be true, but just because we (or specifically you) do things one way now and our expectations for boating to destination x in time frame y, doesn't mean behaviors won't change in the future. New boaters might end up with a whole different attitude.
 
That may or may not be true, but just because we (or specifically you) do things one way now and our expectations for boating to destination x in time frame y, doesn't mean behaviors won't change in the future. New boaters might end up with a whole different attitude.

If you want to use your boat in a different way from how the typical trawler operates, then battery electric might be a fit. It works in little Duffy tour boats, and is being tried (and presumed to be successful) in short haul operations along with necessary support infrastructure changes.

I don't think any technology is inherently good or bad. It's just a question of where it fits. There is nothing inherently bad about batteries and electric motors - just the opposite. And nothing inherently bad about other power sources. You just need to find good matching applications.

The point of my post is that trawlering as we typically know it today is not a good match for battery electric. If boating habits change and you suggest they might, and if infrastructure evolves so faster charging is practical, then the fit of battery electric in boats could well change. I just don't see either of those things happening very quickly. And although there has been a bump in battery technology over the past 10-20 years, it only represents a 3x improvement over LA which has been around for 100+ years, and we are still off by a factor of 35x from having something comparable to carrying fuel.
 
Twistedtree makes a good point.

Perhaps you've seen Hinkley's electric yacht DASHER, which has received breathless reviews in some of the yachting mags. Hinkley's website indicates a cruising range of 20 to 40 miles.

Seriously.
 
Regardless of your politics (and I think both extremes have it wrong) the world is moving away from fossil fuels, for a number of purely economic reasons.

Wind and solar are getting cheaper, while fossil fuels are not. CO2 and pollution are certainly bad things, but it doesn't really matter just how bad you think they are.

There are already large all-electric ferries in service. Just as there are all-electric cars which work well for some people.

We're not quite at the point where a general-purpose, all-electric vehicle of any kind is really ready. Cars are just about there. Trawlers are a ways off. Airplanes maybe never.

Before you point to Tesla and the rest, those don't meet my definition of ready; an affordable vehicle which can take a family on a two-week vacation covering 300-600 miles per day, with all their luggage. Refuel time is also an issue.
 
Twistedtree makes a good point.

Perhaps you've seen Hinkley's electric yacht DASHER, which has received breathless reviews in some of the yachting mags. Hinkley's website indicates a cruising range of 20 to 40 miles.

Seriously.


You know, a true picnic boat might actually be a reasonable application. I expect lots of boats (but not your typical trawler, I don't think) probably don't venture more than 10-20 miles, and then spend days at a dock. So I could see cases where it might fit. But you still have such a disproportionate amount of space occupied by batteries vs comparable range from stored fuel. It's real hard to see how that's the best use of space on a boat.

For the near term, I think all these electric and hybrid boats are basically lifestyle choices that come at an extra cost vs the alternatives. But there are lots of things that people will pay more for to demonstrate style, personality, values, or whatever.
 
I can see applications where an electric motor makes a lot of sense. To me an electric outboard on small sailboat makes lots of sense. I think a lot of sailors power away from the dock and out to open water, then sail around.....and at the end of the day, power back to the dock. They could get by with 3 or 4 hours of electric run time. Add some wind/water/solar capability and the equation gets even better.

The old couple that putt-putts around the lake for a few hours on their pontoon boat could be electric

The guy who wants to take his kids tubing for an hour or so.

The engines for these applications are already in existance. As more of them get sold and used, improvements will come.

Look at car engines, and how far they have come in the last 25 years in terms of efficiency ( both mpg and HP/cubic inch ) Ford has a 2.7 liter engine in a full size pickup that can tow 8,000 pounds !! That would not have been possible a short time ago.

As for subsidies and incentives for electric vehicles or home solar installations; these things benefit all of society, and that's exactly what the government is supposed to be doing. You want to cry "let the market decide" ??? Do you think Walmart could stock its shelves if the Federal Government didn't maintain a highway system and a railroad... Or maintain ports, dredge channels, launch satelites and place nav aids ? If you really want to get down to it....a large percentage of Walmarts employees are below the poverty level and recieving assistance for housing, food and fuel. So the US Gov't is also subsidizing Walmarts labor costs as well.

Everyone benefits if I burn less oil, so its fair and equitable that everyone pay to help me do that. As members of a society we have to pay for what's good for that society, not just the resources that we use. If you don't have kids in school, you still have to pay for your local school system, because society needs it. Even if your house didn't catch fire, you have to pay for a fire department.... its just part of living in an organized society.
 
Twisted Trees calculations are quite interesting.
However a kWh in diesel gives a lot less energy at the wheel (or prop) than a kWh of stored electrical energy. With diesel you have to burn it first and there are a lot more moving parts in a diesel engine than an electric motor. Because of the losses in heat about 30% of diesel energy gets used for drive, for stored electric energy it is more like 90%.
It isn't practical to charge at 50 amp through your shore power feed, most new dedicated installations now are around 50 kW as charging times become important with the larger battery banks.
Battery size and life are still major problems but many manufacturers will now offer warranty for ten years, so expected useful life will be more, no doubt.
 
Twisted Trees calculations are quite interesting.
However a kWh in diesel gives a lot less energy at the wheel (or prop) than a kWh of stored electrical energy. With diesel you have to burn it first and there are a lot more moving parts in a diesel engine than an electric motor. Because of the losses in heat about 30% of diesel energy gets used for drive, for stored electric energy it is more like 90%.

I took that into account in the calculations. The KWh for diesel is the amount usable for propulsion. I used 20hp-h/gal for the prop power from a gal of burned diesel. As you point out, the raw energy in that gal is much higher.

It isn't practical to charge at 50 amp through your shore power feed, most new dedicated installations now are around 50 kW as charging times become important with the larger battery banks.

Maybe for automotive charging stations, but there aren't any of those on docks. I picked 50A/240V because that's the highest power, commonly available outlet capacity. Reality though is that many docks doen't even have that. And just look at all the discussions about marinas where the power was designed assuming much lower consumption by each boat, and now have low voltages because everyone is running AC on their boat. Based on how slow marinas are changing to accommodate air conditioning, I wouldn't hold my breath for 50KW electric charging stations. You might get lucky at a super yacht dock and get a 100A/240V outlet (24kw) which would reduce the recharge time down to less than 3 days. I think most of the world would still find that unacceptable. And if you are really lucky, you might get a 100A 3ph outlet and reduce your charge times to 24 hrs or so. But wow, those will be some mighty big chargers.

Battery size and life are still major problems but many manufacturers will now offer warranty for ten years, so expected useful life will be more, no doubt.

Agreed. At 3000 cycles, you could use the boat almost daily for 10 years. But I still think $750k to buy the battery bank will be a deterrent for most buyers. That's more than the value of most TF boats, and way more than the value of a diesel power plant.
 
Sorry I missed the "usable" bit which makes it all work.

Yes the charger size is scary as well and to my mind prohibits "full electric" trawlers.
Probably also long haul trucks, unless you swap the battery banks rather than charge them in place.
It's all fine and dandy if you just charge one truck or trawler.
But if you want to charge 20, or 50 you will need a decent sub station to cope.

Not to be too negative however for day or picnic boats you can do it now.
Also metro delivery trucks, which is the most obvious use of the current technology.
 
The point of my post is that trawlering as we typically know it today is not a good match for battery electric. If boating habits change and you suggest they might, and if infrastructure evolves so faster charging is practical, then the fit of battery electric in boats could well change. I just don't see either of those things happening very quickly. And although there has been a bump in battery technology over the past 10-20 years, it only represents a 3x improvement over LA which has been around for 100+ years, and we are still off by a factor of 35x from having something comparable to carrying fuel.


I appreciated your post. It helped put into perspective the basic realities of energy storage and utilization on boats like ours.

Maybe one of you engineering types can answer this... how much loss is there in diesel/electric motors? Assuming that diesel fuel will still provide the bulk of stored energy, is it at all reasonable to consider going that route and then using wind and solar to supplement the diesel?
 
Maybe one of you engineering types can answer this... how much loss is there in diesel/electric motors? Assuming that diesel fuel will still provide the bulk of stored energy, is it at all reasonable to consider going that route and then using wind and solar to supplement the diesel?

In the context of TF trawlers, I think it's extremely unlikely that a diesel-electric will bring any benefit, and is more likely to actually be less fuel efficient. And it will definitely cost more to build.

In a classic diesel-electric, the diesel turns a generator to generate electricity, and the electricity drives an electric motor to turn the prop. This is in contrast to the diesel directly turning the prop via a gear.

The conventional drive has single digit power losses in the gear. Say 5% for arguments sake. So of the power available at the engine flywheel, 95% of that is available to the prop.

For a diesel electric, the is about a 10% loss in the generator powered off the flywheel. That power gets rectified to DC, then runs through a VFD (a speed and power control) to drive the electric motor. That's about another 10%. Then there is the electric motor which is about another 10% loss.

So right out of the gate in the diesel electric, you have lost 30% between the engine and prop, where with a conventional drive you have lost 5%. That puts you 25% in the red. Now it may not be quite that bad, or it may actually be worse. But let's give diesel-electric the benefit of the doubt and say it's only 15-20% in the red. Now you need to make that up somehow.

The efficiency argument for DE is that you can run the diesel at a more efficient RPM/load and gain better fuel efficiency. With a gear drive for every prop load level, there is exactly one engine RPM/load point that you can use. The engine can actually generate the same HP for the prop at a wide range of rpm/load points. Lower rpm + higher torque gives you the same HP, and with DE you can pick any one of those operating points.

At different rpm/torque points, engines burn different amounts of fuel even though all points product the same net HP. Since you can pick any rpm/torque combination that produces the desired HP, you can pick the one that does so with the least fuel burn. That gains you back some efficiency.

Every engine's fuel efficiency is depicted in a "map" that looks much like a topo map. One axis is rpm and the other it torque. The contours in the map show the fuel burn to produce power at that particular rpm/torque point. Given the way the maps are done, the "high ground" in the topo is the most efficient, and the valleys are the worst. In a DE, you try to always run the engine on the "hill tops". With a gear drive, you can only operate at points along a single line that curves across the map.

The bottom line question with a DE is whether you can operate the engine on hill tops that are enough higher than the fixed gear line, and do that often enough to make up the 20% deficit that are starting out with, let along actually do better than a gear drive.

I guess that was a really long way of saying No.
 
Yes, but....

So I am not typical, I run about 1.5 gals/hr. 10 hours of running time is about right as a longer day is very tiring.

I,m not a big must have a marina spot. But if I could run for ten hours and recharge for 12, and avoid the gas dock, oil changes, analyzing exhaust, the noise, starter batteries, I might never go on the hook again.

Then of course there is the coming technology of the fuel cell -say goodby to the genset
 
"Instead he with the help of environmentalists convinced (suckered) our government to shell out huge subsidies (paid by taxpayers) for his gamble."

Teslas cash (his cars are losers) actually comes from selling indulgences.

A fast car (gas hog ) is forced to pay a special fine to Unkle Sam.

The size of the fine can be offset by purchasing credits from a "less polluting " car maker.

As electric from nuke power plants is clean Tesla gets credits to sell with every car he builds at a loss.

Works for him , but the public is, as always the looser.

This exactly what an incentive program is SUPPOSED to do: it stimulates the production of goods in the public interest. The "looser" or tighter public benefits from the introduction of vehicles that can be powered with 100% renewable energy as the grid converts, something that fossil fueled ICEs cannot do. If you believe that carbon caused climate change is a Real Thing, then you will like this sort of thing, if you don't then you won't.
 
New things are popular or even big fads.
In this country there’s plenty of people that want the brand new latest thing whether it works better or not.
The smart guy will buy the electric vehicle when it becomes cost effective. There will be/are plenty of people “leading the way” for us lesser folks.

I like the DE and if I could afford one I’d buy it. There’s lots of advantages.
 
The smart guy will buy the electric vehicle when it becomes cost effective. There will be/are plenty of people “leading the way” for us lesser folks.

That's how I see it too. Once it becomes practical & economically advantageous, I'll have an electric car, a Tesla PowerWall and some of those very cool solar shingles on top of my house that Tesla is developing.

Until then, it's for the early adopters or for those wanting to make a statement.
 
While I consider myself an environmentally focused consumer, as an electrical engineer I have to laugh at this notion of 'electric barges'.



1) Where is the electricity coming from that charges the batteries?
2) What is the efficiency of converting the alternating current from the grid to direct current to charge the batteries? Hint: Ever hear of I-squared-R losses?

3) Did anyone do the math to actually KNOW whether an electrical propulsion system for these barges has a lower carbon footprint than a modern diesel plant? Hint: The answer is NO.


Converting chemical or thermal energy to electrical energy is surprisingly INEFFICIENT. Especially if you have to pull A.C. power from the grid and then convert it to DC to charge batteries. If one was to do an end-to-end analysis of the typical "electric" boat, one would discover that the environmental benefits are virtually meaningless. An 'EPIC FAIL' in environmental terms.


If you are going to burn fossil fuel to move a boat or a barge, there is no benefit to converting fossil fuel energy to electricity before using it to move the boat!


We need to keep the focus on replacing electricity from carbon fuels (coal/oil/gas) with electricity from non-carbon sources. Only AFTER we do that will electric propulsion make any sense.


Where are our Thorium reactors? Oh...sorry...dumb question. Thorium nuclear reactors are useless for making fissionable bomb-making materials.



https://en.wikipedia.org/wiki/Thorium-based_nuclear_power
 
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I think a major tipping point could be when solar and the storage of it can be more cost efficient than straight diesel.
 
"the introduction of vehicles that can be powered with 100% renewable energy as the grid converts,"

There is not enough food in the world to burn it all to operate our society.

"a major tipping point could be when solar and the storage of it can be more cost efficient than straight diesel."

After 125 years of battery development , the newest battery systems still seem 100 years from having the dame energy density as diesel.And still have charging and discharging losses.

A new type diesel engine would be a big help.

So far the only first electric attempt that makes economic sense is harbor tugs.

Tugs can shut down the big diesels,,, go to and loiter on station on batteries awaiting the arrival of the next job.

The diesels will do 99% of the work docking ,, BUT as the hourly price of the boat is figured by peak" bollard pull" the ability to parallel the bats and diesel to the shaft would earn money all the time.

Not burning fuel idleing , and not putting hours on the big diesels also helps the bottom line.

Electric power will only make sense when folks make money by adapting the tech.

Forced "development " is another Solindra , very profitable for a few political folks ,loosing multiple millions for tax payers.

I believe gov. development money can be wisely spent only when the development will truly advance science or engineering.

There is no profit in an engine mfg spending R&D bucks developing a very different style engine , even if it is 30% more efficient.

While the customers would LOVE it,,, the requirement to scrap all the existing production facilities and build new ones would not go over with stockholders .

In the USA DARPA performs this function , of attempting to jump rather than crawl R&D.

In the past Honda Motorcycles solved its problem by just building a new factory for 1st world sales and keeping the old factory to build for 3rd world markets.
 
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Meanwhile back to the future. Use sails and a diesel kicker. Recently while at Rodney Bay in St Maartens, I noted the serious cruising public has voted- sail boats. If the zealots want to take away our motor vessel, a whole host of nice sail boat choices awaits.
 
If you are going to burn fossil fuel to move a boat or a barge, there is no benefit to converting fossil fuel energy to electricity before using it to move the boat!

We need to keep the focus on replacing electricity from carbon fuels (coal/oil/gas) with electricity from non-carbon sources. Only AFTER we do that will electric propulsion make any sense.

That is the point in both the article on the electric barges and the one on the Swedish ferries that I linked. In both cases, the companies plan to use carbon-free power sources like solar, wind, or water to generate the electricity to fuel the battery banks on these boats (the barges use battery banks in the containers).

Jim
 
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Can’t believe what I’m hearing.

Electric is cool, modern, in .. and the latest so to speak.

But what bewilders me is why there’s not a lot of talk about more fuel efficient hull designs, smaller boats and more efficient engines and more fuel efficient ways to use them.

Instead there’s this Lemming like rush over to electric.
 
That is the point in both the article on the electric barges and the one on the Swedish ferries that I linked. In both cases, the companies plan to use carbon-free power sources like solar, wind, or water to generate the electricity to fuel the battery banks on these boats (the barges use battery banks in the containers).

Jim


I saw that, thanks. My response was an attempt to answer the question -- "When a Tesla trawler?". As long as we live in a world where the vast majority of electricity comes from carbon fuels, a "Tesla trawler" does not make sense.


Too much focus on making vehicles that run on electricity and not enough focus on where the electricity is coming from is (both figuratively and literally) putting the cart before the horse.
 
A harbor tug might actually be a good application for a hybrid diesel electric. They have massive power requirements while moving a boat, but then much more modest requirements the rest of the time. I don't know what the duty cycle is, but it would been to be pretty small at high power.


So you could run smaller diesels to generate electricity and provide transport propulsion, charge a large battery bank for the heavy loads, then use the stored electric power to augment for the giant loads. It's classic peak load shaving using stored power.
 
Too much focus on making vehicles that run on electricity and not enough focus on where the electricity is coming from is (both figuratively and literally) putting the cart before the horse.


I think both are happening. The improved efficiency of the delivery and the use of electricity, no matter what vehicle, lowers the AMOUNT of fossil fuels we use. Couple that with the exponential increase in solar and wind farms (and cleaner burning and more available natural gas) and electric vehicles continue to become a better source for future transportation.



HOWEVER, diesel, in regards to boating, may never make much sense. At least not anytime soon. The reliability of having a readily available and long-use power source when offshore or a long way from a battery charging will be preferable for many, many years to come. I could see it in port boats like tugs since they are never far from home and could spend the time recharging (assuming the non-use makes financial sense... and charging times aren't ridiculous). But losing charge in, say, the Alligator-Pungo Canal or in Glacier Bay, while not "dangerous", would be damn inconvenient.



The recreational boater would have to set new expectations for electric to work. Shorter travel days and required stops to recharge will slow travel times. A lot of hurry-up people would have a hard time adjusting, but new boaters mat embrace it. Additionally, the infrastructure of wilderness charging stations probably make little sense and could really prevent boaters getting to the places they want to go.


Certainly there is a long way to go, but dismissing it because it isn't great now is underestimating what mankind is capable of.
 
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