Hybrid Theory

[mbianka]

I'll be starting my seventh season with my electric propulsion system and a poor man's hybrid (Honda 2000 gennie) setup and am not looking back. When I made the leap from diesel to electric in 2008 in the back of my mind I always thought my backup would be an installed marine diesel. Would not even consider it now with my experience using the Honda. The Honda has too many advantages in terms of cost, weight, reliability and ease of maintenance. For bigger boats than my 30 footer yeah then a more powerful inboard diesel makes sense. If I never have to go below and to work/maintain a diesel engine below decks again color me happy. Nice thing about electric propulsion there are a number of various ways to make it work and modify it down the road as things change/advance. Though I have not seen a reason to change my system since the install.

[a64pilot]

Not everything is as it seems.
Wife has driven a Prius for the last four yrs, commuting about 100 miles each day, and pretty much any speed above 42, your out of hybrid mode and mostly just like any other car, except that your not an Otto cycle engine, your an Atkinson cycle engine and you can use the electric propulsion for a boost to climb hills and for accelerating etc, so it's very easy to get above 50 mpg, and at steady state cruise a Prius at 60 mph is returning close to 60 mpg. (know as the rule of 60 to hypermilers)
So in four yrs of ownership and about 125,000 miles so far, I can tell you it's by far the cheapest thing we have ever had, total cost of ownership.
I can't quote you any articles proving anything, I've just had one for the last four yrs and her average commute is 100 miles a day.

But back on track,
If fuel cells ever become viable, it'll change cruising, be at least as big a change as FRP was.
Imagine, almost limitless electrical power, which brings all kinds of evils , like AC, unlimited fresh water, unlimited hot water etc. all without the noise and vibration of a generator. (yes, you will have to have the fuel though, darn I knew there would be a catch )

[tdoster]

Originally Posted by a64pilot

Not everything is as it seems.
Wife has driven a Prius for the last four yrs, commuting about 100 miles each day, and pretty much any speed above 42, your out of hybrid mode and mostly just like any other car, except that your not an Otto cycle engine, your an Atkinson cycle engine and you can use the electric propulsion for a boost to climb hills and for accelerating etc, so it's very easy to get above 50 mpg, and at steady state cruise a Prius at 60 mph is returning close to 60 mpg. (know as the rule of 60 to hypermilers)
So in four yrs of ownership and about 125,000 miles so far, I can tell you it's by far the cheapest thing we have ever had, total cost of ownership.
I can't quote you any articles proving anything, I've just had one for the last four yrs and her average commute is 100 miles a day.

But back on track,
If fuel cells ever become viable, it'll change cruising, be at least as big a change as FRP was.
Imagine, almost limitless electrical power, which brings all kinds of evils , like AC, unlimited fresh water, unlimited hot water etc. all without the noise and vibration of a generator. (yes, you will have to have the fuel though, darn I knew there would be a catch )

I am not quoting articles, I owned one. What you are not calculating is the actual cost per mile, which you can't calculate until you are actually finished with the car and sell it or dispose of it. It may be the most reliable thing you have ever driven and you actually get all 50 MPG, but that means little when you go to sell it and find it has lost more value than you made up with the economy. You are happy with it and can relate it to reliability and daily economy - fixed cost: My payments are X, I pay Y for gas, and don't care what it is worth after it is paid off...

Sorry, WAY OFF TOPIC.

But how this relates is looking at the big picture. One poster is very happy with converting to electric, and more power to him, but to really discuss the economy of scale, you have to look at what is that boat worth at the end of the day. Will someone pay more for it and recoup the expense, probably not. If you remove it from the boat after 30 years, what value will it have compared to a 30 year old Volvo MD2? So, there is the residual effect on all this that can't be computed until the end of life. Does it make him happy, just as you are happy with your Prius - Yes. That is what is important.

Then what are you comparing the reliability of electric versus diesel in your experience? Is it the 30 year old diesel that was in the boat prior, or compared to a new repower? What will the reliability of the electric be after 30 years of marine exposure? How many batteries will need to be replaced over that time period? What will be the residual value of the equipment? If I calculate my engine requirements for a passage at approximately 3 hours per day, will the electric handle that as well as the normal electricity demands of the boat without shore power? What is the residual value of an EU 3000 Generator that is not built for marine environments and have maybe a 10 year Duty Cycle @ 2K each. I have a 10 year old EU 3000 that is now maybe worth $500 from salt exposure so being conservative.

I still stick to the best way to go about it (~30 Footer) would be an electric outboard as a hybrid approach which would probably offer the best long term return as it is portable and retains far greater residual value. There is no major modification to the boat other than a bracket on the stern and it was designed and built for the marine environment.

Everything else is really as hypothetical as an article in Popular Science of what the future may bring.

[mangomuffins]

mbianca,

Looking to repower the Vega w/ elec (10KW/48V motenergy motor & sevcon gen4 controller)... any suggestions?

mm

[mbianka]

Originally Posted by mangomuffins

mbianca,

Looking to repower the Vega w/ elec (10KW/48V motenergy motor & sevcon gen4 controller)... any suggestions?

mm

Sounds like you have plenty of power. My boat weighs 8 tons and I'm using a 9 HP Lemco motor. Not familiar with the Montenergy motor but, sounds like it may also be based on the Cedric Lynch design too.

I went with AGM batteries and am still very happy with the choice. They are holding up well after seven seasons. Still not sure I would switch to Lith Ion when it comes time to replace either. I wanted to have a system that if a battery went south on a cruise down the ICW or anywhere else for that matter I would be able to replace it in a reasonable amount of time. Lith Ion still has delivery issues. Something to think about if you are paying marina fees waiting for delivery. Also they are more expensive and requires a little more watching and BMS electronics i.e. more complexity. I'm a K.I.S.Sailor.

I have two 48 volt solar panels and 48 volt Marine Air-x wind turbine along with a Honda 2000 generator for charging as I am usually at anchor or on a mooring. I love making fuel at anchor using solar and wind. But, it's best to recharge the batteries ASAP so the Honda comes in handy for that. But, once charged don't usually need to fire it up until it's time to pull up the anchor. Also it can move the boat at 3 knots (without drawing any amps from the battery bank) using only 900 watts of power and run until the gas runs out which is four hours with it's one gallon tank.

Recently added a 48 volt pure sine inverter which will allow me to tap into the 10 kw battery bank while at anchor and not have the need to fire up the generator. For things like a quick vacuum or laptop use.

Kept my 12 volt house and propulsion banks separate. Always want to have a backup and not have all the electronic eggs in one basket.

Maintenance has been near zero compared to having a diesel. Love that the bilge and boat always smell clean.

That's a few things off the top of my head. In short I love EP think you will too.

[mangomuffins]

thanks mike,

I appreciate the input.

[pdf27]

Originally Posted by tdoster

The problem is not creating electricity, the problem is there are no current breakthroughs in storing electricity. That is a huge hurdle to leap before we can turn it all from theoretical to practical.

Was bored today and started looking at the website for Oxis Energy (they're a Lithium-Sulphur battery developer located in the same science park that I work in). The table below shows what they expect their technology to be capable of by year. Within about 3 years, they expect to get to capacities of 0.3 kWh/kg for cells with a 2,000 cycle charge/discharge life. That's essentially the reliability of LiFePO4 at a third of the weight and is getting towards the point where they might be marginally viable production batteries. I should point out that these batteries don't suffer the thermal runaway problems that Lithium-Polymer batteries do - you can shoot them and they go on working quite happily.

Going back to my post #49, a diesel engine consuming fuel at a rate of 59 kW appears to be roughly equivalent to a 12kW electric motor in thrust terms. As diesel contains 11 kWh/litre, then a 12 kWh Li-S battery (weighing 40 kg) is equivalent to 5.3 litres of diesel weighing 4.5 kg.

Hopeless for cruising any distance, but for day/weekend sailing where you are otherwise tied up at a marina it starts to make sense. At 40kg for an hour at full speed, you're looking at maybe 200kg for a weekend's usage - with fuel virtually free afterwards and close to zero maintenance. If you're going further afield things get harder to justify however - that sort of system only makes sense if you have reliable shorepower.

[Andrew Troup]

One underappreciated consequence of the bonanza which the concentrated energy content of fossil fuels represent: we have developed unrealistically wasteful norms around installed power requirements.

I'm thinking of the peak power output of auxiliary engines routinely fitted to sailboats these days, where their ridiculous over-abundance of power is only partly due to the inability of IC engines to develop usable amounts of torque at lower revs.

Still, if they could, (and if fossil fuels were priced closer to the cost of replacement) I'm sure variable pitch props would be much more prevalent.


I was struck by how a little power can go a long way on reading about Airbus's electric concept plane:

<< It can get up to a respectable 220km/h - with a cruising speed of 160km/h - on its 30kW engines and it only cost US$16 (NZ$18.58) per hour to power, as opposed to the US$55 (NZ$63.86) for a similarly-sized jet-fuel guzzler, but that's a far cry from being useful in the commercial space.


It gets its juice from 120 250V Li-ion batteries stored in the wings and can keep the plane in the air for around 45-60 minutes, with a recharge time of one hour.



The Airbus brochure mentions that a quick-swap system would vastly decreased the time it takes for it to get back into the air.>>