Outboards are incredibly polluting - WOW

[zstine]

Originally Posted by Tupaia

When will people get off of the solar band wagon there are places with NO SUN.

Fine, replace "solar array " with "renewable power source" And my statement holds true. regardless,
my point was that recharging an E-motor with an ICE generator makes no sense.

[Rumrace]

When was the last time you had 5 gallons 30 pounds of gas on your Dinghy to feed a 2-5hp motor. Are you travelling the Amazon.
5 gallons of gas almost last me all summer on an 18 yr old Yamaha.

[Dockhead]

Originally Posted by zstine

Fine, replace "solar array " with "renewable power source" And my statement holds true. regardless,
my point was that recharging an E-motor with an ICE generator makes no sense.

No sense from an environmental point of view, or at least, little sense (efficient diesel generator pollutes a lot less than inefficient small spark ignition engine, enough to more than make up for the inefficiencies in converting back and forth to and from mechanical to electrical power, and storing it). Actually that's not true -- if you charge the outboard battery from shore power or from your alternator when motoring, you will save a lot of pollution.

But in any case, the environment is not the only reason to use an electric outboard.

[Adelie]

Originally Posted by Tupaia

When will people get off of the solar band wagon there are places with NO SUN.

Yes, there are places and Times of day & year with no sun.

Doesn’t mean EP wouldn’t work then or there in a some limited fashion.

Why should people need to have dinghy propulsion that works at full power at all times and in all places? That seems to be what you are implying.

A majority of cruisers cruise in sunny areas.
Even those who overwinter in the Med where is is cloudy for extended periods get some insolation.

[NPCampbell]

Originally Posted by Adelie

You are both wrong but in opposite directions.

4-stroke outboards get 5-7hp-hr/gal. Assuming high end that’s 7hp-hr/gal * 0.746kW/HP = 5.222kWhr/gal at the prop.

The Renogy has 1.2kWhr of energy at 100% discharge. Assuming 80% discharge and 95% motor efficiency then 1200Whr * 0.80 * 0.95 = 912Whr usable at prop.
5,222 / 912 = 1/5.7 gal equivalent.

The Torqueedo Travel 1103 has a 915Whr battery according to their site. I assume that’s usable.
915Whr * 0.95% efficiency = 869Whr.
5222 / 869 = 1/6 gal equivalent.

Let me provide you with some alternate facts Capacity is simple and doesn't involve efficiency or fuel consumption of either motor. 1 gallon of gas equivalent is 33.7kWh (using the EPA def). 915wH Torqeedo battery / 33.7kWh = 1/37 GGE.

I'm assuming you were involving fuel consumption rates to take into account the inefficiency of gas engines to make the electric range look better?

Three things:
1) You make the assumption that the Torqeedo is 95% efficient. However, with 1100 watts of power it only generates 520 watts of propulsive force. That's less than 50% efficient. How much of that is slippage? Heat?
2) Typical fuel consumption rates for modern EFI 4 stroke outboards at WOT is approx .1 gal/HP/hr. Carb outboards are slightly worse. Some of the DI models with lean burn will be 20% better than this.
3) It's immaterial. For $15 I can fill a standard 3 gallon tank of gas that will let a 3 HP motor run for over 8 hours at WOT. To get 8 hours of range in a Torqeedo at WOT would require a $4k battery like the ePropulsion E175.

There are definite use cases for the current crop of electric motors. However, for me, the range, expense, weight and charging time of a battery that can support a planing motor are the limiting factors.

[Dockhead]

Originally Posted by NPCampbell

Let me provide you with some alternate facts Capacity is simple and doesn't involve efficiency or fuel consumption of either motor. 1 gallon of gas equivalent is 33.7kWh (using the EPA def). 915wH Torqeedo battery / 33.7kWh = 1/37 GGE.

I'm assuming you were involving fuel consumption rates to take into account the inefficiency of gas engines to make the electric range look better?

Three things:
1) You make the assumption that the Torqeedo is 95% efficient. However, with 1100 watts of power it only generates 520 watts of propulsive force. That's less than 50% efficient. How much of that is slippage? Heat?
2) Typical fuel consumption rates for modern EFI 4 stroke outboards at WOT is approx .1 gal/HP/hr. Carb outboards are slightly worse. Some of the DI models with lean burn will be 20% better than this.
3) It's immaterial. For $15 I can fill a standard 3 gallon tank of gas that will let a 3 HP motor run for over 8 hours at WOT. To get 8 hours of range in a Torqeedo at WOT would require a $4k battery like the ePropulsion E175.

There are definite use cases for the current crop of electric motors. However, for me, the range, expense, weight and charging time of a battery that can support a planing motor are the limiting factors.

You're comparing apples and oranges. HP at the prop does not consider prop efficiency, and is not the same as propulsive power. Adelie's calculations are correct.

But your conclusion is correct. If you need enough power to plane a dinghy, an electric motor is not for you. Electric is only practical for displacement speed running over moderate distances.

Electric is a somewhat costly but very attractive alternative to a 2.5hp or 3.5hp outboard for those of us who primarily use the dinghy for ferrying to shore over moderate distances. Would be no good for the Caribbean.

[wingssail]

For my situation an electric outboard just would not work. It would involve considerable loss of utility which I now enjoy.

Speed: probably the least important. I can do without the ability to plane, that just means giving up longer distances, so less exploring, and slower trips to shore. (Shrug)

Load carrying: While cruising we often bring several large shopping bags of provisions back to the boat (a few hundred pounds). Sometimes we need to transport people, four to six. I guess a 3hp could do it but I have my doubts. This goes back to speed. We could transport the goods or people, just A LOT slower.

Fuel: This spring while we cruised in remote areas for three months we ran our dingy daily, for short trips and did a few longer trips, mostly at slower speeds (but still much faster than a three hp motor could do it) and we used only 6 gallons of gasoline. No practical amount of batteries would do that without refilling (recharging). So with electric we'd have to be concerned every day about power for the electric. With the IC engine we filled it up once before departure and otherwise simply ignored the fuel issue.

I would enjoy a nice, stowable, sailing dingy, because that fuel is free, but honestly, In my experience it is not often windy enough to sail a dingy, and besides, stowing one would be an issue for me.

Recharging: If we were docked with shore power every day this would be a no brainer, except for the electric bills, but at anchor we'd need a better electric power source than we have now. We have a simple boat, no genset and limited solar (280watts), and no wind gen which would be useless anyhow. Assuming that we'd need about 1000wH more electric power daily, on the average, for the dingy that would mean over 80AH per day or about 1 hour daily running the engine. That cost in diesel would add up over a month.

Simple boat: OK, we could build an arch and put a solar array on it, for sunny days, or buy a portable generator, but we have chosen a light, simple, sailing boat because we like to sail. I really don't want to change our whole approach to boating to accommodate an electric dingy motor.

Durability: Our 15HP Merc has been running very well and very reliably for 22 years with absolutely minimal maintenance or problems. I don't worry about it, I just use it, and I expect it will run for a few more years just the same as it has been. I don't know about the electric and particularly the batteries or the electronics.

Conclusion: For us the 2 stroke Merc is a perfect solution and I'd hate to give it up.

Lets talk about pollution. I agree that the IC motors are heavier polluters, and the two stroke motor like mine are the worst, and I don't mind doing my share, but if we are really serious about protecting or cleaning up the environment we should tackle the polluters which make a big impact and not waste our time with the little stuff which does very little other than make ourselves feel good. Worrying about the small amounts which come from a clean burning 4 Stroke gasoline dingy motor is mostly virtue signaling when we ignore jet aircraft and ocean going ships and other heavy polluters. It's like beach clean-ups or other small attempts at reducing plastic. It seems silly when we ignore major plastic polluters. We are just kidding ourselves when we ignore the many large cities, mostly in Asia and Africa, which dump tons of plastic into their rivers which flow into the oceans.

You should try to sail across Manila Bay. For 28 miles we saw a floating plastic bag every 48", in every direction including downward.

If we're serious let's do something serious not just play little "feel good" games.

[Lake-Effect]

Originally Posted by wingssail

Conclusion: For us the 2 stroke Merc is a perfect solution and I'd hate to give it up.
...
If we're serious let's do something serious not just play little "feel good" games.

This is the crux of the problem isn't it; everyone else must change first, then maybe me. Well ok, have you voted for the guys who want to clean up the big messes, or the guys who say everything's ok/there's not a serious problem/we'll adapt?

Not blaming you personally, we have a small 2-stroke too. But we need to own our share of the problem, and to be pulling together for the big solutions we claim have to happen first.

[goboatingnow]

I agree we all need to own our share of the pollution issue and it behoves the wealthy , ie us, to do what we can. To that end for practical reasons I drive an EV. But for outboard the cost benefit advantage is poor and until that improves I’ll stay with my 4 stroke

I do agree with the 2 stroke ban.

[GreenWave]

Originally Posted by wingssail

For my situation an electric outboard just would not work. It would involve considerable loss of utility which I now enjoy.

Speed: probably the least important. I can do without the ability to plane, that just means giving up longer distances, so less exploring, and slower trips to shore. (Shrug)

Load carrying: While cruising we often bring several large shopping bags of provisions back to the boat (a few hundred pounds). Sometimes we need to transport people, four to six. I guess a 3hp could do it but I have my doubts. This goes back to speed. We could transport the goods or people, just A LOT slower.

Fuel: This spring while we cruised in remote areas for three months we ran our dingy daily, for short trips and did a few longer trips, mostly at slower speeds (but still much faster than a three hp motor could do it) and we used only 6 gallons of gasoline. No practical amount of batteries would do that without refilling (recharging). So with electric we'd have to be concerned every day about power for the electric. With the IC engine we filled it up once before departure and otherwise simply ignored the fuel issue.

I would enjoy a nice, stowable, sailing dingy, because that fuel is free, but honestly, In my experience it is not often windy enough to sail a dingy, and besides, stowing one would be an issue for me.

Recharging: If we were docked with shore power every day this would be a no brainer, except for the electric bills, but at anchor we'd need a better electric power source than we have now. We have a simple boat, no genset and limited solar (280watts), and no wind gen which would be useless anyhow. Assuming that we'd need about 1000wH more electric power daily, on the average, for the dingy that would mean over 80AH per day or about 1 hour daily running the engine. That cost in diesel would add up over a month.

Simple boat: OK, we could build an arch and put a solar array on it, for sunny days, or buy a portable generator, but we have chosen a light, simple, sailing boat because we like to sail. I really don't want to change our whole approach to boating to accommodate an electric dingy motor.

Durability: Our 15HP Merc has been running very well and very reliably for 22 years with absolutely minimal maintenance or problems. I don't worry about it, I just use it, and I expect it will run for a few more years just the same as it has been. I don't know about the electric and particularly the batteries or the electronics.

Conclusion: For us the 2 stroke Merc is a perfect solution and I'd hate to give it up.

Lets talk about pollution. I agree that the IC motors are heavier polluters, and the two stroke motor like mine are the worst, and I don't mind doing my share, but if we are really serious about protecting or cleaning up the environment we should tackle the polluters which make a big impact and not waste our time with the little stuff which does very little other than make ourselves feel good. Worrying about the small amounts which come from a clean burning 4 Stroke gasoline dingy motor is mostly virtue signaling when we ignore jet aircraft and ocean going ships and other heavy polluters. It's like beach clean-ups or other small attempts at reducing plastic. It seems silly when we ignore major plastic polluters. We are just kidding ourselves when we ignore the many large cities, mostly in Asia and Africa, which dump tons of plastic into their rivers which flow into the oceans.

You should try to sail across Manila Bay. For 28 miles we saw a floating plastic bag every 48", in every direction including downward.

If we're serious let's do something serious not just play little "feel good" games.

Wingsail- um, I agree with 95% of what you said. But please don’t trivialize the plastic pollution problem and attempts to clean it up. Local beach cleanup efforts, while not having a global impact, do provide measurable relief for local habitats. Plastics pollution is already a problem and soon will be our #1 issue. I am making a concerted effort to reduce the use of single use plastics in my life.

[Rumrace]

Many moons ago in a 270 SeaRay I drifted behind the reeds drives up engines off tossed a hook and drifted in. I tied a line to a tree and used the Dinghy to deliver table chairs and BBQ. While cooking we noticed a King Rattle Snake which just ate something huge or was pregnant.
But to the outboard part. In the morning I was too shallow to drop the drives I need 3’4” to get them in. I strapped the Dinghy to the side of the ray and with a 4hp 4stroke Yamaha I towed the Ray into deep water. Wife warmed up the motors while I fought Gloucester Pool current. Amazing little motor. 2 SeaRays and a Jeanneau later on it’s 3rd Dinghy the SSE III Running perfect 18 years old .
Pry it off my dead hands

[Lake-Effect]

And of course, everything is relative. If someone drives everywhere in a Ram quad-cab with a hemi, and takes 6+ round-trips by plane a year, then the pollution from their dink's outboard - 2- or 4-stroke - isn't even a rounding error on their carbon/pollution footprint.

[Dockhead]

Originally Posted by Lake-Effect

And of course, everything is relative. If someone drives everywhere in a Ram quad-cab with a hemi, and takes 6+ round-trips by plane a year, then the pollution from their dink's outboard - 2- or 4-stroke - isn't even a rounding error on their carbon/pollution footprint.

Yes, and don't forget consumption of meat and dairy.


Nothing wrong with WingSail's approach -- he doesn't own a car as far as I know, and travels by wind power. His annual dinghy fuel consumption is probably less than a week of fuel for the family cars of the average American family. He needs range and power in his dinghy for his use case. There's nothing wrong with what he's doing.

[Lake-Effect]

Originally Posted by Dockhead

Nothing wrong with WingSail's approach -- he doesn't own a car as far as I know, and travels by wind power. His annual dinghy fuel consumption is probably less than a week of fuel for the family cars of the average American family. He needs range and power in his dinghy for his use case. There's nothing wrong with what he's doing.

I haven't questioned or criticized his use of his outboard, I just commented on the sort of self-justification he's built up around it, and on some plastic bans..."what about Asia?" etc.

I do believe there are justifiable and rational uses of fossil fuels; it's amazing stuff with unmatched energy density. Real cruising would currently be impossible without it. The real question is why we waste so much fossil fuel, and more every year, depleting a finite resource, with the attendant pollution, environmental damage, and geopolitical consequences. Conservation is a dirty word, efforts to find and use alternatives are sneered at...

Yes, and don't forget consumption of meat and dairy.

This is an important consideration for a bunch of reasons, but you have not yet backed your contention that it's the single largest source of greenhouse gases. I posted something from the EPA waaay back that indicates that all agriculture contributes less than 1/4 of the global emissions, and energy generation and transportation together still contribute more than 1/2 the amount.

[Tupaia]

Originally Posted by Lake-Effect

Conservation is a dirty word, efforts to find and use alternatives are sneered at...

I don't think anyone on here has sneered at attempts to utilise alternative energy. I for one certainly do not decry any means available.


I do however object to the evangelical stance of eco warriors who have no understanding or empathy for the circumstances of others and have a narrow self centred and totally unrealistic view of the real world.



in my experience cruisers in general are a very ecologically minded bunch with a minimal carbon footprint compared to the general population.



If electric outboards were $30 each it would still not meet the real needs of the majority of live aboard cruisers.