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This is awesome. I lived on a sailboat for a while and sometimes you get cloudy weather for days, blocking your ability to use solar to top up your batteries. T

This is awesome. I lived on a sailboat for a while and sometimes you get cloudy weather for days, blocking your ability to use solar to top up your batteries. The small M35 universal diesel engine I had had one thing going for it, it had a lot of torque. Torque I use to turn a 110V 120A alternator. The alternator (like a car’s) charges the battery, except in my case it was charging a lot of battery. 6 12V 200AH Lithium Iron batteries. These batteries ran all the “home” appliances for several days before needing a recharge. 120V 3000W inverter, A/C, Fridge, coffee maker, water maker, electric stovetop, lights, navigation, radio, Starlink, Xbox. If having a vehicle is unsightly, you can remove the engine onto a stand and wire it up exactly as described in this video. The only thing you’d need to run an engine is a fuel line, a spark, and compression.

doubled112 3y ago
If you go diesel, you remove the need for spark, but perhaps starting is a greater challenge.
bluGill 3y ago
You also need a cooling system to run nearly all engines. Generally a car engine doesn't have enough cooling system to run at max power for very long (it is only a few seconds between the light turning green and you being at speed, then you need much less power). Your sailboat as the nearly infinite ocean to cool itself with. Most likely your engine also needs a computer, which implies an electrical system.
- rcostin2k2 3y ago
  Living on a sailboat, the cool water would not be a problem. Just some filters to avoid clogging the cooling ducts.
- mschuster91 3y ago
  > Most likely your engine also needs a computer, which implies an electrical system. Old diesel clunkers not really, at least if you don't care about emissions control. Fuel injection / exhaust valve control is purely mechanical, all they need electricity for is the engine starter and, depending on age, the cooling fan. Modern engines, on the other hand, these can be really hard to run on their own outside of a car, at least from hearsay - I only have had experience with an 1994 VW T4 van.
  - yetihehe 3y ago
    I've tried with Opel from 2004. I had a very modern version (with everything over CAN, even gas pedal) and I had to disconnect A LOT of sensors in order for it to no longer start (don't ask why). Modern diesel cars are a little worse for this, because of all the emissions regulations requiring adblue and dpf filters to work correctly. If you run out of adblue in some cars, you have to get it towed to dealer for checkup and reset.
    - deleted 3y ago
      [deleted]
  - doodlebugging 3y ago
    >all they need electricity for is the engine starter and, depending on age, the cooling fan. If you get an old enough diesel engine or can do the mod yourself you don't even need an electric starter. The first diesel engine I worked on used a gasoline engine as a "pony motor" to spin the diesel engine flywheel enough to generate the compression needed to start the diesel engine. From memory (probably wrong haha) you cranked the gasoline engine and brought it up to high rpm and then you started the diesel engine using a lever that gradually engaged the diesel engine flywheel bringing it up to operating speed. Once the diesel engine was running you backed off the lever and killed the gasoline engine. An obvious disadvantage would be the necessity to maintain stocks of two fuel types. Other than that it is a near fool-proof way to handle cranking a diesel engine. The electric starter is replaced by the gasoline engine and flywheel linkage. You effectively roll-start the diesel using the gasoline engine.
    - jaggederest 3y ago
      Video of this in action: https://youtu.be/AL0ls_UpT8w?t=361 https://youtu.be/AL0ls_UpT8w?t=361 The whole video is worth a watch, but I linked directly to the timestamp where he begins to explain how the engines are started with a petrol starter. To power a foghorn. Amazing stuff.
      - doodlebugging 3y ago
- numpad0 3y ago
  I think everyone here is underestimating power density of a car engine. GP's alternator is 110V/120A, that's 13.2kW, or up to 8-way tea kettle boiling or Xeon workstation use simultaneously(1.5kW each). Chances are you won't be running 4 YouTuber editing machines, 2 pots cooking on IH stoves, 2 air conditioners and a USB-PD laptop charger all drawing full amount inside the living quarter on a sailboat. That's before counting in 6x 12V/200Ah = 14.4kWh battery system which safely doubles, possibly quadruple instantaneous draw.
  - JoeAltmaier 3y ago
    Most household requirements are about 13kW. So not much different than your suburban bungalow needs.
    - numpad0 3y ago
      I think there's something wrong with your palace if you're maxing out 100A breakers, that's 720[hr] x 13[kWh] x 0.30[$/kWh] = $2.8k/month. Even if you meant 1/3 duty it's $936/month. Average household usage in US is 20-40kWh/day... not sure where does 13kW figure fits in that picture.
      - custard42 3y ago
        they missed a decimal point. Average US household consumption over a year is approx 1.25KW.
      - JoeAltmaier 3y ago
        200A service is standard transformer to a house.
        numpad0 3y ago
        Constant 50% utilization is not!
        JoeAltmaier 3y ago
zirgs 3y ago
Wouldn't it make more sense to install 230V on a boat? Modern electronics handle 100-240 anyway and you can save on cables.
- bluGill 3y ago
  Boats are typically so small that you can use smaller cables without problem even at 120 volts. Many of them run only 12 volts (often most things like lights and radios are run on 12 volts, but the owner as an inverter for a couple appliances they can't find in 12 volt). Of course nobody runs smaller cables at 120 volts because you would need an engineer to figure out the proper rating - it is cheaper to just use the standard code wires. If you do pay an engineer you will probably discover on boats you need to use the larger wires anyway for mechanical reasons.
  - LeifCarrotson 3y ago
    Having wired up a couple travel trailers and a boat (and, incidentally, being an EE who can theoretically run those calcs), I agree with the parent: It would be better if the industry switched to 120V/220V AC for more parts, and away from 12V. The problem is that the ampacity in a 12V DC light circuit is 10x that of an equivalent-power 120V AC system. And worse yet, power dissipation in a resistive element is equal to I^2 R, so you're heating the wiring harness with power losses are 100x worse than in a 120V system and almost 200x worse than a 220V system. So you have to oversize the wires to reduce R, which adds weight and cost. And if you drop 2V to line losses in your 12V system, your device is seeing 83% of the nominal voltage, while if you drop 2V in a 120V system (you won't, because Ohm says voltage drop is equal to IR, and I is 1/10th that of a 12V system), but still, you're 98% nominal. They're running 12V because that's the voltage of a classic 6-cell lead-acid battery, and you probably didn't want 220V in your Model T, even with felted asbestos insulation, but I'd be confident enough to lick a modern XLPE wire carrying 220V. A century of using those lead acid batteries (and worse, 3-cell 6V systems...can't endorse converting your classic car to 12V enough...) created now-entrenched economies of scale for lamps, and switches, and pumps, and radios, and fans, and most of the other things you need in a boat or camper. The only advantage of using those 12V parts is that their manufacturers put a little more effort into making them efficient. No one (sadly) will notice or care if the AC-DC converter that runs the clock on your stove burns 5W at idle even though your wall clock can run on one AA battery for years, but they will notice and care if their camper battery is dead after leaving it parked for a couple weeks. Today, I recommend using LiFePO4 batteries in whatever series cell arrangement gets you the required watt hours, regardless of that output voltage. Then run a modern, high-efficiency (high-frequency) digital inverter to bump the voltage up to whatever your local AC grid runs at. You can go 220V AC in the US if you really want more efficiency and smaller wires, and are willing to deal with the hassle of finding the right lightbulbs and international power cords and so on.

doubled112 3y ago

If you go diesel, you remove the need for spark, but perhaps starting is a greater challenge.

bluGill 3y ago

You also need a cooling system to run nearly all engines. Generally a car engine doesn't have enough cooling system to run at max power for very long (it is only a few seconds between the light turning green and you being at speed, then you need much less power). Your sailboat as the nearly infinite ocean to cool itself with. Most likely your engine also needs a computer, which implies an electrical system.

rcostin2k2 3y ago
Living on a sailboat, the cool water would not be a problem. Just some filters to avoid clogging the cooling ducts.
mschuster91 3y ago
> Most likely your engine also needs a computer, which implies an electrical system. Old diesel clunkers not really, at least if you don't care about emissions control. Fuel injection / exhaust valve control is purely mechanical, all they need electricity for is the engine starter and, depending on age, the cooling fan. Modern engines, on the other hand, these can be really hard to run on their own outside of a car, at least from hearsay - I only have had experience with an 1994 VW T4 van.
- yetihehe 3y ago
  I've tried with Opel from 2004. I had a very modern version (with everything over CAN, even gas pedal) and I had to disconnect A LOT of sensors in order for it to no longer start (don't ask why). Modern diesel cars are a little worse for this, because of all the emissions regulations requiring adblue and dpf filters to work correctly. If you run out of adblue in some cars, you have to get it towed to dealer for checkup and reset.
  - deleted 3y ago
    [deleted]
- doodlebugging 3y ago
  >all they need electricity for is the engine starter and, depending on age, the cooling fan. If you get an old enough diesel engine or can do the mod yourself you don't even need an electric starter. The first diesel engine I worked on used a gasoline engine as a "pony motor" to spin the diesel engine flywheel enough to generate the compression needed to start the diesel engine. From memory (probably wrong haha) you cranked the gasoline engine and brought it up to high rpm and then you started the diesel engine using a lever that gradually engaged the diesel engine flywheel bringing it up to operating speed. Once the diesel engine was running you backed off the lever and killed the gasoline engine. An obvious disadvantage would be the necessity to maintain stocks of two fuel types. Other than that it is a near fool-proof way to handle cranking a diesel engine. The electric starter is replaced by the gasoline engine and flywheel linkage. You effectively roll-start the diesel using the gasoline engine.
  - jaggederest 3y ago
    Video of this in action: https://youtu.be/AL0ls_UpT8w?t=361 https://youtu.be/AL0ls_UpT8w?t=361 The whole video is worth a watch, but I linked directly to the timestamp where he begins to explain how the engines are started with a petrol starter. To power a foghorn. Amazing stuff.
    - doodlebugging 3y ago
numpad0 3y ago
I think everyone here is underestimating power density of a car engine. GP's alternator is 110V/120A, that's 13.2kW, or up to 8-way tea kettle boiling or Xeon workstation use simultaneously(1.5kW each). Chances are you won't be running 4 YouTuber editing machines, 2 pots cooking on IH stoves, 2 air conditioners and a USB-PD laptop charger all drawing full amount inside the living quarter on a sailboat. That's before counting in 6x 12V/200Ah = 14.4kWh battery system which safely doubles, possibly quadruple instantaneous draw.
- JoeAltmaier 3y ago
  Most household requirements are about 13kW. So not much different than your suburban bungalow needs.
  - numpad0 3y ago
    I think there's something wrong with your palace if you're maxing out 100A breakers, that's 720[hr] x 13[kWh] x 0.30[$/kWh] = $2.8k/month. Even if you meant 1/3 duty it's $936/month. Average household usage in US is 20-40kWh/day... not sure where does 13kW figure fits in that picture.
    - custard42 3y ago
      they missed a decimal point. Average US household consumption over a year is approx 1.25KW.
    - JoeAltmaier 3y ago
      200A service is standard transformer to a house.
      - numpad0 3y ago
        Constant 50% utilization is not!
        JoeAltmaier 3y ago

zirgs 3y ago

Wouldn't it make more sense to install 230V on a boat? Modern electronics handle 100-240 anyway and you can save on cables.

bluGill 3y ago
Boats are typically so small that you can use smaller cables without problem even at 120 volts. Many of them run only 12 volts (often most things like lights and radios are run on 12 volts, but the owner as an inverter for a couple appliances they can't find in 12 volt). Of course nobody runs smaller cables at 120 volts because you would need an engineer to figure out the proper rating - it is cheaper to just use the standard code wires. If you do pay an engineer you will probably discover on boats you need to use the larger wires anyway for mechanical reasons.
- LeifCarrotson 3y ago
  Having wired up a couple travel trailers and a boat (and, incidentally, being an EE who can theoretically run those calcs), I agree with the parent: It would be better if the industry switched to 120V/220V AC for more parts, and away from 12V. The problem is that the ampacity in a 12V DC light circuit is 10x that of an equivalent-power 120V AC system. And worse yet, power dissipation in a resistive element is equal to I^2 R, so you're heating the wiring harness with power losses are 100x worse than in a 120V system and almost 200x worse than a 220V system. So you have to oversize the wires to reduce R, which adds weight and cost. And if you drop 2V to line losses in your 12V system, your device is seeing 83% of the nominal voltage, while if you drop 2V in a 120V system (you won't, because Ohm says voltage drop is equal to IR, and I is 1/10th that of a 12V system), but still, you're 98% nominal. They're running 12V because that's the voltage of a classic 6-cell lead-acid battery, and you probably didn't want 220V in your Model T, even with felted asbestos insulation, but I'd be confident enough to lick a modern XLPE wire carrying 220V. A century of using those lead acid batteries (and worse, 3-cell 6V systems...can't endorse converting your classic car to 12V enough...) created now-entrenched economies of scale for lamps, and switches, and pumps, and radios, and fans, and most of the other things you need in a boat or camper. The only advantage of using those 12V parts is that their manufacturers put a little more effort into making them efficient. No one (sadly) will notice or care if the AC-DC converter that runs the clock on your stove burns 5W at idle even though your wall clock can run on one AA battery for years, but they will notice and care if their camper battery is dead after leaving it parked for a couple weeks. Today, I recommend using LiFePO4 batteries in whatever series cell arrangement gets you the required watt hours, regardless of that output voltage. Then run a modern, high-efficiency (high-frequency) digital inverter to bump the voltage up to whatever your local AC grid runs at. You can go 220V AC in the US if you really want more efficiency and smaller wires, and are willing to deal with the hassle of finding the right lightbulbs and international power cords and so on.