Boat propulsion. Is electric actually green?

flaming

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Anchors are an important diversion of this thread. We’ll end up doing a fair bit more anchoring if we’re electric auxiliary powered. No spare energy to just push the tide regardless.
Just energise the seabed and use the anchor as the connector. So anchoring just becomes stopping for a charge..... ;)
 

Bouba

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The majority of the hospitality sector now relies on domestic brand LED screens which fail at 18-36months when used for 14hrs a day.
However there are lots of old plasma screens in Wetherspoons that I fitted around 20 years ago still running on obsolete signal formats
My LED TV is on a lot longer than 14 hours a day…it’s several years old now
 

Neeves

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As I walk round marinas I note that a large number of yachts are plugged into mains power, do they leave the fridge on?

I also note that some yachts have a reasonable solar display (I have not correlated mains power connections and solar displays).

Many of the owners of the yachts in marinas have careers, how else do you afford the sort of yacht that is kept in a marina. The yachts are thus unused 5 days of the week.

I assume that the solar display are professionally installed and once the batteries are full charged then the solar controller shuts down the solar power. Another example of profligate waste.


To be truly green the marina should be harvesting the unused solar. It does not seem a major technical issue, as with a domestic roof display, for the marina to encourage owners, with decent solar displays to 'come to the party'.....or not?

Jonathan
 

johnalison

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As I walk round marinas I note that a large number of yachts are plugged into mains power, do they leave the fridge on?

I also note that some yachts have a reasonable solar display (I have not correlated mains power connections and solar displays).

Many of the owners of the yachts in marinas have careers, how else do you afford the sort of yacht that is kept in a marina. The yachts are thus unused 5 days of the week.

I assume that the solar display are professionally installed and once the batteries are full charged then the solar controller shuts down the solar power. Another example of profligate waste.


To be truly green the marina should be harvesting the unused solar. It does not seem a major technical issue, as with a domestic roof display, for the marina to encourage owners, with decent solar displays to 'come to the party'.....or not?

Jonathan
Our marina has a large solar collection area in an adjacent field and aims to be self-sufficient, though I don’t suppose its usage is particularly large. I tend to leave my boat plugged in for two reason, ignoring the winter dehumidifier. I find it handier to have it plugged in even if not in use so that I can boil a kettle or use the heater without using gas or the batteries. Also, my solar panel only connects to the service batteries and it is easier to keep all the batteries fully charged, the current usage being minimal.

On a particularly hot day in Stralsund a nearby sailing boat that was probably about 50’ had its engines running all day, annoying many of us with the noise and fumes, even though electricity was readily available. Eventually I braced myself to walk over to ask them in a language I didn’t understand to desist, but was saved by meeting a fellow sufferer who was on his way to do the same. I say that electricity was available, but the system was one of the most baffling I encountered. I had cracked the system in previous years and often had to explain to visiting Germans how to make it work, which I found very satisfying.
 

lustyd

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As I walk round marinas I note that a large number of yachts are plugged into mains power, do they leave the fridge on?
Mine has always been permanently connected as I used to leave the smart charger on to look after the batteries. Now we're lithium based I turn off the shore power to prevent the battery being topped up but still leave it plugged in for convenience because we often stay on the boat in the marina when we're not sailing.
 

Sea Change

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Is there a forward thinking marina that would put solar panels over the pontoons, creating shade/rain shelter and generating power at the same time? Not all marinas have adjacent fields. But all have a lot of walkways
It's a nice idea, but I think in practice most pontoons are too narrow and too exposed to wind for this to work in anything other than light drizzle.
Probably better to install on the roof of the facilities etc.
 

Mark-1

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It's a nice idea, but I think in practice most pontoons are too narrow and too exposed to wind for this to work in anything other than light drizzle.
Probably better to install on the roof of the facilities etc.

The amount of use many boats get you could float solar panels on the water with a retraction mechanism for occasions when someone wanted to leave.
 

chriscallender

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some trained electric eels might be useful.
When my kids were young they were always trying to hang cables connected up to their Nintenodo DS over the side with exactly this plan to charge their batteries when they ran out. Actually they were a bit confused between jelly fish and electric eels as well (both would hurt if you touched them, which to them was plenty good enough also to charge a battery :) )
 

Tranona

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You are correct in your first sentence.

Just out of interest what are the fundamental differences and what are the similarities?

Jonathan
This has been covered in various earlier posts but to summarise from the report the fundamental difference is in the usage pattern. For a car the carbon cost of manufacture and disposal is estimated at 30% and for a boat at 60%. This reflects to much lower usage over the life of a boat and unlike a car it will probably never offset the sunk carbon cost through the lower carbon cost of using even renewable electricity for propulsion.

On the other hand the argument in favour of EV cars with their higher usage might be able to. however a you see from some posts this is highly contested and it all depends on the assumptions you make about what the costs of manufacture are and the usage/life patterns. Optimistic on the first costs and pessimistic on the second can lead to wildly different conclusions as some of the examples given show.
 

Chiara’s slave

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Is the report assuming that a brand new electric boat is built to replace an ICE one? Rather than conversion?
And if you really want to skew it you can factor in scrapping the ICE boat too. You can say anything you like with numbers if such stuff is not made explicit. If a set of numbers doesn’t include the assumptions made, it's best completely disregarded.
 

Tranona

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Is the report assuming that a brand new electric boat is built to replace an ICE one? Rather than conversion?
It does not say. If you mean what is the incremental carbon cost of making an electric car vs an ICE one, then I guess this is one of the assumptions that would contribute to the difference in outcomes of the calculations. I have not looked in detail at the assumptions underpinning the calculations of the cost of manufacture. Doubt that ICOMIA did any calculations for cars but would have taken the results of existing studies.

Important to remember the objective of the study which was to identify the factors related to decarbonisation and the recreational boating industry, not to take any position on either whether it is right or wrong or whether one approach to deal with it better than another. However it is pretty clear whatever assumptions you make that electric power for boats for the current pattern of usage is not viable.
 

flaming

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It does not say. If you mean what is the incremental carbon cost of making an electric car vs an ICE one, then I guess this is one of the assumptions that would contribute to the difference in outcomes of the calculations. I have not looked in detail at the assumptions underpinning the calculations of the cost of manufacture. Doubt that ICOMIA did any calculations for cars but would have taken the results of existing studies.

Important to remember the objective of the study which was to identify the factors related to decarbonisation and the recreational boating industry, not to take any position on either whether it is right or wrong or whether one approach to deal with it better than another. However it is pretty clear whatever assumptions you make that electric power for boats for the current pattern of usage is not viable.
The other thing that the report seems to miss is that the batteries that come out of the boat at end of life (and I'm still super skeptical about the replace every 10 year claim) can be recycled.

The current estimate is that for an tesla battery at end of life, of the roughly 800kg of material, less than 50kg is not recyclable.

And even before then there will be a use for old "capacity limited" batteries to use as storage. If you're putting them in a container, for example, the fact that what started out as 100kWh is now 60 is not an issue when the battery is second hand and cheap. It's only when the space you have is limited that you are worried about deterioration.
 
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