Jimmy Cornell goes Electric, with a Cat

[Pete7]

Originally Posted by Franziska

Not sure if been mentioned in the thread, but despite the cooker (to my knowledge) "Sailing Uma" claims in their latest YouTube video that they are cruising already 5 years fossil fuel free...

Interesting video by the way.
https://youtu.be/JHUQiRyVV3Y

Actually, your cat is probably pretty low impact compared to most folk living in the EU.

Are you thinking of changing btw, given the Lagoon 38 query?

Pete

[harlem24]

Originally Posted by Pete7

At 50' North we run the diesel heating regularly. We need about 1.5kw during the winter with temperatures between 5-10c and 1kw during a wet weekend in the summer.

Diesel for heating is kind of difficult to replace, a lot of bang for the buck in a gallon of diesel. Charcoal or wood whilst great at home wouldn't be my first choice on the boat.

Pete

Sure, but for a heating system you wouldn't need tank with hundrets of liters capacity...
And if you wanted you might use a propane heater.

[Patg]

Looks like he intends to sail through strait of magellan in patagonia.
Can be quite chilly there without heating.....


https://cornellsailing.com/2020/01/t...e-is-electric/

[mglonnro]

Originally Posted by harlem24

Sure, but for a heating system you wouldn't need tank with hundrets of liters capacity...
And if you wanted you might use a propane heater.

Also, there is/will be renewable diesel. Don't know if the heaters work on that yet, but I if not now, I assume they will. https://www.neste.com/nexbtl-renewab...ce-boat-owners

And the fuel cells ... https://www.viessmann.co.uk/products...cell/vitovalor

Anyway, I think it's incredibly exciting when people test new innovations in real life and pave the way for the crowd to follow... or realize the madness

[b_rodwell]

What an amazingly good idea!!!!

With a few caveats and qualifications I think a lot (maybe a majority) of cruisers would be better off with this idea. The caveats/qualifications are:

Low Latitude Sailors -- Less likely to have long overcast periods. No high latitude sailing.

My Sort of Cruising -- Never leave port when strong winds are forecasted. Very rarely leave port when the forecast is headwinds. If you are going even partly around the world, go west - less headwinds even on long passages. Rarely or never motor at maximum speed.

Apples against Apples -- You need to define the starting point for any comparison. The base I have used for comparison is an Outremer 45 like Jimmy's boat but fitted out conventionally for a boat of this type - 2 diesel engines, 2 saildrives, genset, solar panels and (say) 600 A/hr of house battery capacity.

These are the changes to go from the base defined above to Jimmy's boat -- Compared to the base above the main differences are: Add 2 electric motors for propulsion, a water generator and 400 A/hr to house batteries; Take Away 2 diesel motors. I think a saildrive for an electric motor would cost about the same as a saildrive for a diesel.

Comparison - Capital Cost -- I don't think there is much difference. I think suitable electric motors would be less expensive than a diesels (this reduces the capital cost) but you need the water generator and it would be sensible to increase the house battery capacity (these increase the capital cost).

Comparison - Operating Cost -- A hands down win for the electric solution. No fuel cost, significantly reduced maintenance cost.

Comparison - Handling Nasty Weather Under Motor Only -- I would expect that the conventional solution could punch to weather in higher winds than the electric solution. At a guess a conventional solution might stop being able to go to windward when the wind strength rises to 35 knots; the electrical solution might stop at 25 knots wind strength.

Comparison - Range Under Power Only -- A clear win for the conventional solution. Under benign conditions the conventional rigged boat may be able to go 500nm; my guess for the electric boat with the genset running would be 250nm.

Comparison - Top Speed Under Power Only -- This might be 11 knots for the conventional configuration compared to 8 knots for the electric. Top speed under power is a question that is often asked. However in 6 years of full time liveaboard cruising I have never had both engines at WOT to achieve top speed under power. I have never been in a situtation that needs it.

For me -- the low operating cost is the glaring advantage. The deciders for me however is are not technical.

Firstly I love not having a diesel engine on and resent starting a diesel engine. More peace and quite.

Secondly I value very highly not having to worry about refueling, buying maintenance consumables (this is a hassle in remote locations) and doing the routine maintenance. I like having more things in the category 'I don't have to think about that'. Cruising always involves having a lot of things you need to worry about. I vote for a change that would reduce the length of the worry list.

One last point. The Outremer base reference is obviously a highcost starting point. Most cruisers would start at a lower cost. I have not done any calculations for a comparison starting at a lower cost so I don't know if that would affect my conclusions.

Lets hear from you.

Brian

[seandepagnier]

If this new boat is built to last a long time it is a great idea. A lot of newer boats will die sooner .

Using old boats is great, but it greatly limits the possibility of more efficient sailing.

As far as propulsion, there is no longer any excuse for using diesel.

[seandepagnier]

Originally Posted by catsketcher

But full power in a squall when you need to motor 3 miles after picking up the anchor is another matter.

during a squall there is wind to sail.

You can sail of course but it would require a large change in how I see many boats used -

The electric motor allows you to sail safely in ports in larger vessels without any risk of running aground or collision and also allowing for tighter tacking. Because most of the power is coming from the sails, the amount of range needed in the electric is very small.

[mglonnro]

Originally Posted by b_rodwell

Comparison - Capital Cost -- I don't think there is much difference. I think suitable electric motors would be less expensive than a diesels (this reduces the capital cost) but you need the water generator and it would be sensible to increase the house battery capacity (these increase the capital cost).

This is an interesting question. I looked at an old offer from the same company that supplies the engines to Cornell's boat, and... well... If not accounting for the expensive lithium batteries, it's merely much more expensive. If adding the batteries (as required), it's hugely more expensive.

I guess prices have come down in a year or so, though. And will come down further. But still, at the moment I think there IS a big difference.

[alex_sauvage]

QUOTE As far as propulsion, there is no longer any excuse for using diesel.[/QUOTE]
If that was the case all new boats would come with electric propulsion. Since 99.9% of new boats still come with a diesel engine, I guess manufacturers know something that you don't.

[MichaelPrichard]

Another often overlooked advantage of electric propulsion (in cars as well as boats), for those of us that keep boat docked in a marina, always having a "full" tank in the morning; no more trips to the fuel dock.

Regarding costs, electric is cheaper if you're not trying to match diesel's range or top speed. You can either forgo the generator altogether (cheapest option with rationally sized battery) or get a small gen and smaller battery as a result. Latter gets you back to "unlimited" range at "cruising" speed relying on battery to provide high power bursts to top speed for 5-10 miles.

I'm starting generator-less with only 10.6kWh of battery (~$3k) so that I can test consumption values at various speeds and get a better handle on how much more battery I'll want to install (in modular fashion, 2 packs a year to spread out the costs). Propulsion system (2 x 7.1kW POD drives and all electronics) = $13k. New diesels (2 x 18hp) would be a lot more, I believe.

[mglonnro]

Originally Posted by MichaelPrichard

Another often overlooked advantage of electric propulsion (in cars as well as boats), for those of us that keep boat docked in a marina, always having a "full" tank in the morning; no more trips to the fuel dock.

Regarding costs, electric is cheaper if you're not trying to match diesel's range or top speed. You can either forgo the generator altogether (cheapest option with rationally sized battery) or get a small gen and smaller battery as a result. Latter gets you back to "unlimited" range at "cruising" speed relying on battery to provide high power bursts to top speed for 5-10 miles.

I'm starting generator-less with only 10.6kWh of battery (~$3k) so that I can test consumption values at various speeds and get a better handle on how much more battery I'll want to install (in modular fashion, 2 packs a year to spread out the costs). Propulsion system (2 x 7.1kW POD drives and all electronics) = $13k. New diesels (2 x 18hp) would be a lot more, I believe.

So when comparing this to Oceanvolt's 10kW saildrive/servoprop (the first version where they include battery costs in the examples):

- 1 x 10 kW saildrive/servoprop
- 13.3 kWh lithium pack
- 2 kW charger
- hydrogeneration

... their starting from price is 32 k€ (saildrive) or 39 k€ (servoprop) so about $35k or $42k.

Isn't that a lot more than you're estimating? Why?

Link: https://oceanvolt.com/saildrive-10/

[MichaelPrichard]

I should've been clearer; I'm using recycled Tesla battery modules which are far less expensive (3-5x less) than new packs, but they're not for the faint of heart and must be handled (electrically) very carefully; Oceanvolts setup is probably using LiFePO4 which are super safe but about half the energy density of the Tesla's and more expensive. One could go the safer recycled route with Nissan Leaf batteries (which are similar to LiFePO4, I think) which have similar densities to Oceanvolts and would cost probably 30-50% of new.

I am going the DIY route to save costs and I'm an engineer not afraid of implementing the needed safety circuits, so perhaps my comparison isn't practical for those hiring this all out. Oceanvolts prices are likely the norm right now for turn-key new installations, but I'm hoping as the popularity goes up that those costs will come down steadily, as they have been the last 10 years.

Regarding the saildrive leg; I've eliminated mine and designed/built custom retractable legs which cost me ~$2500 in welded 316 Stainless, the POD drives are wonderful options here as they eliminate all gearing which even the Oceanvolts have, so regen should be more effective/efficient.

I guess I should've qualified my assertions of lower cost toward the "engaged" DIY owner which many of us are, or are somewhere along the spectrum...

[mglonnro]

Originally Posted by MichaelPrichard

I guess I should've qualified my assertions of lower cost toward the "engaged" DIY owner which many of us are, or are somewhere along the spectrum...

Thank you for doing it! It was really interesting.

My question was quite sincere, just looking for info. I really want Oceanvolt (and their competitors) to succeed, and I was wondering if they are doing something sub-optimally since they appeared much more expensive.

But now I understand! Thank you.

[Brewgyver]

Originally Posted by boat_alexandra

As far as propulsion, there is no longer any excuse for using diesel.

That's quite a short-sighted statement.

Case in point, a YouTube boat that almost sank last year because they replaced their diesel with electric.

To make a long story short, hull opened up on passage crossing the Caribbean, with the winds and current were against them. By the time they used up their battery power (which was not long at all), they were still more than 60 miles offshore.

If it hadn't been for a fishing vessel in the vicinity who happened to have some emergency hull repair goop, they would have lost the boat.

[b_rodwell]

I forgot 2 more things in favour of going electric:

1. It was picked up by another poster that going electric is 'greener'.
2. 99.5% of cruisers would like more stowage space. If you go electric you loose the space taken up by your additional (lithium) batteries but you gain the space taken up by, in my case, 2 diesel engines. More space to store all those things you will never need.

I think I will go out and order one!

Brian