How About No More Electric Boats?

Discussion in 'Boat Design' started by DogCavalry, Mar 18, 2021.

  1. DogCavalry
    Joined: Sep 2019
    Posts: 3,076
    Likes: 1,569, Points: 113
    Location: Vancouver bc

    DogCavalry Senior Member

    I appreciate the starry eyed urge to tread lightly, etc. But.

    The environmental impact of Li-ion battery production is very high. Significantly higher than oil production on an energy storage basis.

    The energy that batteries store is almost never made from angel farts. About 90% of energy production world wide is still produced from burning fossil fuels. There are line losses in transmitting electricity. In some regions up to 60%. So the electric boat in those areas burns more fossil fuel than a regular internal combustion engine equipped boat.

    The energy density of a good battery is about 1/40th that of gasoline. Worse for diesel. So the boat has 1/40th the range, or 40 times the weight of fuel in batteries, at massive cost, and significant penalty in energy efficiency because of the weight penalty. And the extra battery weight is made at huge environmental cost. Teslas are 4 door cars. Because they need the frame space.

    Folks get their information about electric vehicles from the marketing departments of companies selling those products. They are about as likely to be telling the truth as a Chevrolet salesman asked by a Ford owner if he should replace his Ford with a Chevrolet. Worse yet are the good and decent folk repeating those lies as if they were fact.

    J
     
    hoytedow likes this.
  2. pironiero
    Joined: Apr 2020
    Posts: 240
    Likes: 18, Points: 18
    Location: Pattaya, TH

    pironiero Senior Member

    yeah, but its new and shiny, so dumbos want it no matter the cost
     
    hoytedow likes this.
  3. rangebowdrie
    Joined: Nov 2009
    Posts: 234
    Likes: 97, Points: 28, Legacy Rep: 10
    Location: Oregon

    rangebowdrie Senior Member

    You guys are overthinking it.
    The solar panels/batteries provide the power to turn the fans that blow air into the sails,, that way you can keep moving even when the wind isn't blowing.
     
    hoytedow, BlueBell and DogCavalry like this.
  4. DogCavalry
    Joined: Sep 2019
    Posts: 3,076
    Likes: 1,569, Points: 113
    Location: Vancouver bc

    DogCavalry Senior Member

  5. BlueBell
    Joined: May 2017
    Posts: 2,677
    Likes: 951, Points: 113
    Location: Victoria BC Canada

    BlueBell . . . _ _ _ . . . _ _ _

    I am really very fond of the panel to motor concept, no batteries.
    Plan accordingly.
     
    Skyak likes this.
  6. philSweet
    Joined: May 2008
    Posts: 2,679
    Likes: 451, Points: 83, Legacy Rep: 1082
    Location: Beaufort, SC and H'ville, NC

    philSweet Senior Member

    There's still good old wet lead batteries. They are nearly 100% recyclable. And relevantly, they actually do get recycled. The cost savings with wet lead battery recycling make them very attractive compared to any other type battery.

    Typical grid transmission losses are 5 to 10 percent. Most places that report higher losses have a problem with unmetered consumption (theft); and that's not an efficiency problem. Slow loads like battery charging are good for the grid in general. If you have load management on the charger, it can be very good for the grid. If you have grid tie charging, it is great for the grid. The grid needs more batteries. So realistically, you can have a transmission efficiency effect through load management that is greater than 100%.
     
    bajansailor likes this.
  7. DogCavalry
    Joined: Sep 2019
    Posts: 3,076
    Likes: 1,569, Points: 113
    Location: Vancouver bc

    DogCavalry Senior Member

    I agree about lead acid batteries, certainly. Efficiency greater than 100% is a system analysis judgement, I'll grant you that as well. Lead acid power density compared to gasoline? Laughable. A very slow displacement boat that uses a massive array of batteries as ballast. Possible.

    Their effect on cargo work done vs carbon output? Questionable.
     
  8. upchurchmr
    Joined: Feb 2011
    Posts: 3,287
    Likes: 259, Points: 83, Legacy Rep: 579
    Location: Ft. Worth, Tx, USA

    upchurchmr Senior Member

    +1 for checking the actual total impact on enviornment.

    But, all the interest will lead to new ideas in how to iplement electric power.
    So there is still the possibility of better effeciency than combustion based power.

    I just don't have the money to fund the development required.
    Combustion didn't get to as good as it is overnight. :)
     
    Will Gilmore likes this.
  9. DogCavalry
    Joined: Sep 2019
    Posts: 3,076
    Likes: 1,569, Points: 113
    Location: Vancouver bc

    DogCavalry Senior Member

    Lead acid batteries have about 1/500 the energy density of gasoline by mass. The electric motor is about 5 times as efficient as the ice at converting energy to motion. So my 26' boat will have about 850# of gasoline on board. 45 tons of lead acid batteries is comparably efficient, right?
     
  10. portacruise
    Joined: Jun 2009
    Posts: 1,475
    Likes: 178, Points: 63, Legacy Rep: 218
    Location: USA

    portacruise Senior Member

    Lithium is not necessarily a permanent solution, there are cleaner cheaper batteries to be developed, and EV batteries can be configured to sell back power into the grid at a profit during Peak demand, if that's what the owner wants to do. If you like gasoline despite all it's detriments, maybe better to use it or methane in a yet to be perfected Automotive fuel cell in an EV which is probably over 90% efficient and without nitrogen oxides pollution? By comparison, around 80% of combustion in engines is wasted as heat and not used to move a vehicle forward, also has to be drained away from them.

    JMHO.
     
    Skyak likes this.
  11. srimes
    Joined: Sep 2008
    Posts: 283
    Likes: 30, Points: 28, Legacy Rep: 214
    Location: Oregon

    srimes Senior Member

    You can't tell me what to do. If I want an electric boat it's my God-given right as an American to buy an electric boat.
     
  12. clmanges
    Joined: Jul 2008
    Posts: 576
    Likes: 144, Points: 43, Legacy Rep: 32
    Location: Ohio

    clmanges Senior Member

    Super-capacitors may someday replace chemical batteries ... maybe. Unlike chemical batteries, they have an indefinite lifespan, and they charge in seconds. Assuming they ever get perfected, though, purchase price will be high because they never need replaced, and they might take up a lot of space.
     
  13. philSweet
    Joined: May 2008
    Posts: 2,679
    Likes: 451, Points: 83, Legacy Rep: 1082
    Location: Beaufort, SC and H'ville, NC

    philSweet Senior Member

    Looking at the propshaft's perspective, you get about 10 hp·h from a gallon of gas and 36 W·h from a kilogram of LAB. That's about 2.75 kg of gas and 206 kg of LAB equivalent. The gas needs a tank and filters and plumbing and pumps and an engine. The LABs need cases and wiring an a charger and a controller and motor. The system weight comparison is highly sensitive to endurance at cruise.
     
  14. Tiny Turnip
    Joined: Mar 2008
    Posts: 865
    Likes: 274, Points: 63, Legacy Rep: 743
    Location: Huddersfield, UK

    Tiny Turnip Senior Member

    Last edited: Mar 18, 2021
    philSweet likes this.

  15. rangebowdrie
    Joined: Nov 2009
    Posts: 234
    Likes: 97, Points: 28, Legacy Rep: 10
    Location: Oregon

    rangebowdrie Senior Member

    At another forum that I was on, a poster wondered why large container ships simply didn't cover the containers with solar panels to provide propulsion,, (use batteries at night).
    They had no idea of the BTUs or KWs necessary to move 100,000 tons, (or more,) at 15 kts,, it's staggering,, not quite like a Prius or a Tesla.
     
    jehardiman and hoytedow like this.
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.