Tesla Electric Yacht unveiled...

[valhalla360]

Originally Posted by Jim Cate

Only place that solar will generate those hours is in polar regions in teh summer. In the tropics, days are never all that long.

A nit-pik for sure, but true!

Jim

Electric production on a cruising boat is typically considered on a daily production basis as wind, sun and generator charging typically follows a daily pattern of peaks and valleys (though each is different from the others).

I stand by the percentage of days where you get meaningful production for each option. I might be off by a few percentage points but not enough to change the main point that a turbine/prop drug thru the water will only be generating power on a very small percentage days while the other options will generate meaningful power far more often.

[EWOL Props]

We have quite some experience on the generation of electricity on and electric powered sailboat.
A couple of years ago we equipped a boat remotorized with electric propulsion.
Our prop has been used to propulse the boat and as a hydrogenerator when sailing for 15 months during a World tour.
When sailing we were able to generate 900W (18,75A - 48V) at 9 knots speed or 400W (8,3A) at 6 knots, which is a very good result ! Much better than the external hydrogenerators thanks to our prop's bigger surface.
If you are interested please watch this video explaining about this project and the results https://youtu.be/_fs91f9C0T0

Originally Posted by Stumble

They work fine, the problem is that to generate meaningful amounts of power you need a boat speed higher than most cruisers achieve. They are pretty much standard equipment on 60' plus race boats, but these are vessels capable of regular 300nm days.

By the time you account for underway power demands (autopilot, radar, electronics, etc) the break even point is that you need to average 5kn speed thru the water. This is actually right at the averages speed most cruising boats under 45' achieve.

So yes it is a reasonable option for either very fast, or very power miser yachts. But for the vast majority of people it's a time best a break even over the long term.

For the same money, another's solar panel would generally be a better bet. Plus they work while at anchor.

[Sandero]

Originally Posted by EWOL Props

We have quite some experience on the generation of electricity on and electric powered sailboat.
A couple of years ago we equipped a boat remotorized with electric propulsion.
Our prop has been used to propulse the boat and as a hydrogenerator when sailing for 15 months during a World tour.
When sailing we were able to generate 900W (18,75A - 48V) at 9 knots speed or 400W (8,3A) at 6 knots, which is a very good result ! Much better than the external hydrogenerators thanks to our prop's bigger surface.
If you are interested please watch this video explaining about this project and the results https://youtu.be/_fs91f9C0T0

Thanks for the vid... impressive and looks like an expensive install with a long period to recover the investment.

Do you think makers could do this sort of thing for OEM propulsion as opposed to diesel... at a reasonable price point?

Also finding the "real estate" for solar may not be so easy... it takes deck space or a structure to plant them.

But the idea is great!

[Racoon]

There we go, finding solutions is always better than finding reasons not to... Now, how much does a conversion cost, what is the real estate needs, etc... Those are the right questions to ask

[IdoraKeeper]

Until we can find a way to induce electrons out of the cosmic scalar field and employ the base level of the intrinsic energy of the universe to our needs we are stuck with what nature provides us. Everything we have is a byproduct of E=mc squared. Even fusion reactions controlled by magnetic fields in a tocamac currently require rotating armatures to induce moving electrons to create the needed magnetic fields. We require a deeper understanding of quantum functions beyond the current probabilistic models. Such understanding will move us beyond the world of Newton into an amazing future. Your "yacht" powered by optimized EmDrive(s) will be equally at home at sea or off the planet in space. Who will be the cruisers then?

Edison and Tesla failed and failed until they created what we have today. Elon Musk will put people on Mars. The person(s) who will make the advancements are likely alive today but we don't know them yet. Fasten your 5 point harness, it's going to be quite a ride.

[valhalla360]

Originally Posted by Racoon

There we go, finding solutions is always better than finding reasons not to... Now, how much does a conversion cost, what is the real estate needs, etc... Those are the right questions to ask

Sorry to burst your bubble:
- 600w solar & 400w wind generator supplying 20,000w of motor
- 38.4kwh battery pack. If wind and solar are maxed out, it will take 38.4hrs to fully charge the battery pack...but solar typically puts out 4-5hrs of the rated capacity per day and wind is highly variable, so figure you have the battery pack filled maybe once a week.
- 2 10kw motors magically produce 45hp? In case you don't know 20kw is roughly equal to 26hp.
- At full output with fully charged batteries, you have less than 2hrs under power to get yourself out of a jam. If you motored for an hour the day before you have maybe an hour of charge.
- This is all before considering house loads.
- As usual for these types of projects, they list a range and the max speed but not the range at max speed or the speed assumed for the given range.

There is no mention of the length but appears to be maybe around a 45' monohull, so 9kts will do-able is a spectacular day under sail. Were the charging outputs mentioned, momentary output or continuous for a say an hour minimum?

In the end looks like lots of pretty graphics but the same wall of physics electric boat proponents always run into.

[Stumble]

Originally Posted by Racoon

There we go, finding solutions is always better than finding reasons not to... Now, how much does a conversion cost, what is the real estate needs, etc... Those are the right questions to ask

/sigh

This does not have any effect on electric propulsion. For propulsion you need storage not generation.

The larger prop size and high average speed of the vessel in this example quite obviously lead to large power generation. But so what? It's the energy storage issue that makes it impractical for the moment. No technology that I am aware of is even close, as in not going to happen in the next 20 years, to providing the type of energy density that diesel does.

Here is the thing, I have always pretty bog standard coastal cruising boat (Beneteau 381). My minimal acceptable range under power is 48 hours at cruising speed, accomplish this and I would seriously consider switching to electric.

So how much stored power do I need to accomplish this? (Assuming 12kwh/h, or 576kwh used)

Diesel - 36 gallons - or 255.6lbs
FLA batteries - 12v * 100ah= 1.2kwh/battery, so 480 batteries, but I need double this to keep then above 50%soc, so I actually need 960 batteries at ~100lbs/battery. Or right in the range of 96,000lbs of batteries.

There is your problem in a nutshell 255lbs of diesel has the same usable power as 96,000lbs of 12v deep cycle FLA batteries.


At the moment the best (excluding price) battery technology for boat's I sure probably LIFEPO. And they are much better than FLA, but are they good enough? Lifepo is both lighter, and has a deeper allowable SOC than FLA so it will certainly be better, but let's see.

A 12.8v at 90ah (1.1kwh) battery weighs in at 35.25lbs. For the 576kwh needed that means 523 batteries or just 18,458 lbs, allow for an 80% depth of discharge and you just need to shoe horn in 22,149lbs of batteries onto a 40' sailboat.


I don't like to mix prices and engineering, because determaning if something can be done is different than if it is cost effective. But here I think it's somewhat instructive to see how far we are from reality. Those Lipo batteries cost about $2,000 each. So even if we figured out a way to get them on the boat, the market price for them would be about 1.25 million USD.

[Paul Elliott]

Originally Posted by Stumble

/sigh

[... excellent analysis of batteries vs diesel energy storage ...]

So even if we figured out a way to get them on the boat, the market price for them would be about 1.25 million USD.

Stumble, you're just not wishing hard enough!

[lordgeoff]

Originally Posted by Stumble

I think the reason people keep showing up hopeing electric can be used on boats is they see the huge gains in cars, and home systems, and simply have no idea how that translates to the demands of a boat. Because electricity pretty much happens in the background there is no real internal quantity that people ascribe to it.

But just as an example, my 40' sailboat needs about 12kw at the prop to operate at cruising speed of 6kn. It doesn't sound like a lot, and it isn't...

But a 100amp breaker box (which is about the average size for a house in the US) when operating at maximum capacity is about 12kw. So my boat just loafing along at a reasonable speed chews thru about as much power as an entire house can. But when was the last time anyone tripped their main breaker? I can't remember ever having done it, sure a 15 amp from time to time, but the main? Never.

At full speed my boat can claw thru about 35kw of power. So it would take the combined capacity of half my block to feed my engine at full power.

The average American home used 900kwh a month in electricity. A gallon of diesel has about 40kwh of power. So the average American home uses the energy equivilant of about 22 gallons of diesel a month, I can burn thru that a day at cruising speed.


But,but,but cars can do it. Ya, but cars power demands are tiny. As in really close to minimal.

The Tesla with its 85kwh battery pack is generally considered a massive one. But that's the functional equivilant of 2 gallons of gas. My boat holds 40 gallons of diesel, so if I convert I need a battery pack roughly 20 times larger than the Tesla has. Figure out the weight, size and cost of that pack and it obviously looks pretty silly to try and stash it on a 40' sailboat.

Even if we could push battery technology to the very limit of physical possibility, they would only be three times more energy dense than they currently are. That means at a minimum you would only need to buy seven Tesla equivilant battery packs. Which is still a tight fit on a 40' boat.


Then you turn to solar... another issue of scale. Modern solar panels are about 20% efficient, and 1m^2 of space will be hit with 1kw of solar energy. So over the course of the productive day of five hours that 1m^2 is hit with a total of 5kwh of power, of which we can capture 1kwh, which is nice because it make the math easy.

Keeping the numbers the same, my boat uses 288kwh a day (12kwh/h*24hours) at cruising speed, so all I need is 288m^2 of solar panels. The problem is my 40' sailboat has a rough surface area of only 45m^2, so even if I can cover 100% of my boat with solar panels I still only have 1/6 the power needed to keep my boat operating at cruising speed.

Even 100% efficient solar panels cannot provide enough power to keep my boat operating at just cruising speed, let alone at high cruise or full power.

But it works on my house right? Ya but on average a house uses 1.25kwh/h in the US. my boat literly uses more power in two hours than the average house will use in a day. So the solar panels for your house simply aren't big enough, and solar radiation simply isn't energy dense enough.


The solution to this frankly is probably renewable liquid fuels. Very high efficiency conversion between electricity and ethanol would work, because ethanol has a reasonably high energy density and it would probably be possible to convert excess solar generated while on the hook to liquid fuels for electrical use later. Combined with the ability to buy ethanol from the dock if you don't have enough for the next passage.

Great summary totally makes sense. Apply the power requirements of a house compared to running a factory and you understand why solar/Battery combinations can't run industry?
Do you have time to compare an average house to a manufacturing factory for example.

[pickpaul]

How about an Uber boat???

[Stumble]

Originally Posted by lordgeoff

Great summary totally makes sense. Apply the power requirements of a house compared to running a factory and you understand why solar/Battery combinations can't run industry?
Do you have time to compare an average house to a manufacturing factory for example.

It very much depends on the factory, and the energy usage relative to the factory roof size. Below are exerts from my and a clients conversation about installing a solat plant on the roof of their factory.


...............................

So I just ran some quick numbers.

If you were install a 10,000m^2 (about 110,000sq ft) solar array on the factory

Solar average is kw/hr/m^2, panel efficiency is about 20%, and South Louisiana gets about 6 hours of solar production a day. So each m^2 generates about 1.2kwh/day. So the array generates about 12,000kwh/day. Now I am using residential rates for power, but Entergy New Orleans charges about $.06/kwh (Xxxxxxxx Mississippi is currently $.0678/kwh) so the panels are generating $720/day or $262,800/year in electricity.

So how much does a 10,000m^2 solar array cost?

Prices are difficult to nail down without getting a quote, but this size power production based on case studies seems to run about $1.3-1.5m depending on how they are mounted (the more expensive mounts generate more power than I assumed).

So for an investment of $1.3m you can reduce power costs by $263,000/ year.

At today's commercial secured interest rate of 4%, the monthly payments on a $1.3m 10 year loan would be $13,100/month or $157,200/ year.

So for every 10,000m^2 you cover in solar panels you save ~$100,000/year in electric cost.

Mississippi and La both have net metering electric bills, so if you actually on net sent power to the electric grid they utility actually has to write you a check to pay for it.

If I am remembering correctly the plant in xxxxxx is about 300,000 sq foot, or about 30,000m^2. So if you covered the entire roof with solar panels at a cost of $3.9m it would reduce the electric bill by about $750,000/year. At an increased cost of about $400,000/year. That's a net profit of $350,000/year with almost no additional cost (solar panels by law are excluded from property taxes).

With an array that size you would probably need to have a full time electrician on staff and someone to full time clean the panels. So figure an increased labor cost of about $100,000/year.

2016 electricity bill ~ $650,000
Net power production value - $750,000


10 year loan repayment cost (annual) - $400,000
Labor cost increase - $100,000

..................................

Back to CForum

In this case not only could the entire plant be run off of solar with net metering, it would actually become a profit center immediately. Now I need this case it is complicated by the fact that a solar array this size has to be licensed as a commercial power plant which requires the approval of the power company, and a lot of safeguards to push that much power back to the grid.

But theoretically it is absolutly possible, in fact there are real advantages to it. Primarily the fact that the structure that the solar array will be mounted to is already a sunk cost. It doesn't add any more to factory maintenance of the building to add solar panels or not.

On the other hand by producing this much power locally the plant can minimize or eliminate power company dictated closed days/shifts due to high power draw.

This is a serious enough investigation that the company is in direct talks with the power company, the State, and has floated bid proposals to three commercial installers. It may not happen, but this type of solar instal is really becoming practical reality as the prices come down.

In this case the factory doesn't draw massive amounts of power, but frankly it doesn't matter much how much power they were using. If every $1 of solar investment offsets more than $1 in present day value cost it is still financially justified. And as of now large arrays like this are very much cost effective.


Batteries are a completely different issue. There are experimental grid scale battery banks, but they are not cost effective or even close so far as I know. Without being able to sell power back to the grid it isn't even worth talking about solar. Even using all the power the panels use during the week the whole scheme hinges on being able to sell excess power back on weekends, holidays, slow days, etc. if you can't sell I think back then it isn't worth doing.


So the problems are primarily regulatory not technical or financial. In time I am sure these will be ironed out.

[valhalla360]

Originally Posted by Stumble

Now I am using residential rates for power, but Entergy New Orleans charges about $.06/kwh (Xxxxxxxx Mississippi is currently $.0678/kwh) so the panels are generating $720/day or $262,800/year in electricity.

The problem with net metering schemes is they take advantage of a flaw in the system (or you could argue a subsidy).

No business buys it's product at full retail prices (could you imagine car dealers buying cars at full MSRP and then selling them at a couple grand under MSRP?).

In addition to eating up the entire profit margin, the power company still has to provide a grid to accept and distribute that power and they need backup generation sources for when the sun goes down (hence the need for battery backup and other storage systems).

Keep in mind, typical peak power consumption occurs early evening, so without a storage system, solar provides almost no reduction in the required production capacity.

The only thing solar provides is a reduction in the actual fuel needed but last I knew that made up only about 1/3 of the kwh price (varies based on production type).

So in the free market solar is no where close to viable on land.

At sea for smaller house loads, it's viable as the cost of an extension cord to connect back to the grid is pretty expensive. For propulsion, it's not even close unless you drastically reduce the motoring capabilities.

[Stumble]

Actually Valhalla it gets very complicated. Because power companies charge the same rate no matter what time of day you use power but solar ramps up at about the same time that power usage climbs. This means that power companies are running peaker plants that cost far more to operate than base load plants.

So in many cases the energy company will be buying solar back at far less than the cost of electricity from peaker plants they would otherwise have to turn on. So they may be buying solar at $.06/kWh and selling it for .06/kWh, but they don't have to turn on a peaker plant that costs $.25/kWh.

At the same time solar obviously turns off at night when the peaker plants turn off, so the energy companies are only selling the cheap base load power.

Net metering may not be fair, it may not be the best option, but it is far more complicated than just 'buy and sell at the same price.'

One way for instance to handle distributed solar that is probably more fair would be to charge everyone for a pro rate share of the cost of maintaining the grid plus a reasonable profit margin, say the same profit margin they are now allowed to make. And seperate power production and power generation into separate entities (this is actually already common in many states).

I am far from an expert at this, but have been following it very closely. And in some cases (like my clients) the power company is actively encouraging us to flip the switch on solar. Because they would rather buy the power from us at .06 then generate it from grid sized diesel generators like they are currently using.

[valhalla360]

Originally Posted by Stumble

Actually Valhalla it gets very complicated. Because power companies charge the same rate no matter what time of day you use power but solar ramps up at about the same time that power usage climbs. This means that power companies are running peaker plants that cost far more to operate than base load plants.

So in many cases the energy company will be buying solar back at far less than the cost of electricity from peaker plants they would otherwise have to turn on. So they may be buying solar at $.06/kWh and selling it for .06/kWh, but they don't have to turn on a peaker plant that costs $.25/kWh.

At the same time solar obviously turns off at night when the peaker plants turn off, so the energy companies are only selling the cheap base load power.

Net metering may not be fair, it may not be the best option, but it is far more complicated than just 'buy and sell at the same price.'

I agree it is more complicated but the peaker plants (along with the grid costs) have to be built to handle early evening peak when solar is putting out nothing.

That $.25/kwh is mostly the cost of the plant and the grid. The actual fuel to power the peaker plants is tiny percentage of the cost. Also, the $0.25/kwh is only that high because they are not being used in a highly inefficient manner, running for a 2-3hrs per day at close to their max output (example: it costs somewhere around $0.50/mile to own a car but if you buy the same car and only drive it 1 mile per month, it might be $300/mile. Same thing with peaker plants.)

Storage is the big stumbling block with large scale solar power production on land and on boats. The only difference is on boats, there are no subsidies.

[Stumble]

Originally Posted by valhalla360

I agree it is more complicated but the peaker plants (along with the grid costs) have to be built to handle early evening peak when solar is putting out nothing.

That $.25/kwh is mostly the cost of the plant and the grid. The actual fuel to power the peaker plants is tiny percentage of the cost. Also, the $0.25/kwh is only that high because they are not being used in a highly inefficient manner, running for a 2-3hrs per day at close to their max output (example: it costs somewhere around $0.50/mile to own a car but if you buy the same car and only drive it 1 mile per month, it might be $300/mile. Same thing with peaker plants.)

Storage is the big stumbling block with large scale solar power production on land and on boats. The only difference is on boats, there are no subsidies.

Like I said, I am not an expert, Andrew value judgments about net metering are above my paygrade. The programs exist, and there is a good argument for them I will leave it at that.

But I just ran across some new information and figured it was worth adding to the conversation.

The new Tesla Powerwall 2 stores 14kwh of power at $5,500/unit with a 10 year replacement warranty. Now they are not suitable for boats at all, but for a home system...

If you live somewhere with time based metering, so you pay more during peak periods it actually starts to make financial sense to buy one of these just to sell back to the grid as a time shifting deal.

Let's assume you are charging the battery at night for .06/kWh. So a full charge costs you about $0.85. Then you sell it back to the grid at $0.24/kWh during peak times for $3.36. So every cycle you make $2.51. Not a lot of money to be sure, but over the course of the year that works out to $916.15, or $9,161.50 over the full warranty lifecycle of the battery.


Tesla has now made battery power cost effective for load shifting. I missed it when it was announced, but this is a major deal. Home based storage is always going to be less cost effective than industrial scale so the prices for them are even cheaper. But more importantly it means that industrial scale battery plants could soon replace peaker power plants cost effectively. Making solar, wave, and wind even more enticing since the power can be stored for later use.

We are really living thru a major change in the entire vision of power distribution and production, and it frankly is unstoppable at this point. Lifecycle costs for some renewables are already below that of fossil fuels (wind and solar are location dependent).

The naysayers may claim renewables aren't cost effective without subsidies, but that's only try because of the massive subsidies that traditional power production already gets. If you exclude all subsidies and tax breaks from all power generation methods renewables actually jump ahead. Because they haven't had the time to build in subsidies the way oil/gas or coal already has.