Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 16-07-2009, 03:24   #1
Registered User
 
AtomicPhil's Avatar

Join Date: Jul 2009
Location: Bronx, NY
Boat: just my arms and legs
Posts: 50
Send a message via ICQ to AtomicPhil Send a message via AIM to AtomicPhil Send a message via MSN to AtomicPhil Send a message via Yahoo to AtomicPhil Send a message via Skype™ to AtomicPhil
Question Solar-Powered Motor

Has anyone tried using a solar powered motor? i was reading up on people who uses solar powered cars and even boats. the boats goes slow compared to the car though . also some youtube videos. so i was thinking if there a way to make or get a motor to use solar energy to run. it helps when theres not enough wind and you need some boost. im not experianced in sailing at all yet. but would like to hear some opinions.
__________________

__________________
AtomicPhil is offline   Reply With Quote
Old 16-07-2009, 06:31   #2
Registered User
 
Alexei's Avatar

Join Date: May 2008
Location: NY (me), Charleston SC (Icefire)
Boat: 1974 Sabre 28 Mk I - Icefire
Posts: 140
Pipe Dream

Whatever that is you're smoking, please hold on to it for about 8 years. I'd like a puff when I'm done in the Navy.

Well, maybe not.....



Point is, all those silly solar cars and what have you are experimental, bare bones, and generally not ready for commercial prime time. Sure, they're fine for some demonstration or some rich guy's lark, but that's about it.

Solar is a great supplemental power source, but for propulsion you just can't get enough energy out with current technology to make it worthwhile on a practical level. Someone correct me if I'm wrong (Gord?).

Unless you're deliberately working to develop a new product or conduct some form of research (as opposed to just wanting to have fun on your sailboat), I'd stick with what's known to work. You'll spend a lot of cash, time, and frustration chasing all these fads and newfangled promising-the-world gadgets, but you'll probably not accomplish a whole lot.


My $.02


-Alexei
__________________

__________________
Alexei is offline   Reply With Quote
Old 16-07-2009, 09:10   #3
Senior Cruiser

Cruisers Forum Supporter

Join Date: Dec 2006
Location: Seattle
Boat: Cal 40
Posts: 2,401
Images: 7
Making poor assumptions, let's say I use 20 HP to move my 40 footer near hull speed in relatively calm conditions. (I know it doesn't convert directly and you can probably get by with a smaller electric motor.) That's about 15 KWatts. Bright sunny day figure 1 KWatt/m^2. So 15 m^2, or 135 sq. ft., or a little under a 12 foot by 12 foot panel if you had perfect conversion of all sunlight during the brightest part of the day.

Grabbing a random 80 W panel, I get a little more than 20x20 feet for current efficiencies.

$3-$5 / watt, $45000 at the low end. If we ever see the new $1/watt panel, $15000.

Add more panels for less than perfect sun, morning, evening, battery charging for night motoring, etc.

John
__________________
cal40john is offline   Reply With Quote
Old 16-07-2009, 10:06   #4
Moderator Emeritus
 
David M's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: San Francisco Bay
Boat: research vessel
Posts: 10,153
There is only so much energy in a square meter of sunlight and solar panels are around 20% efficient, 40% at best. For it to work, I think we would have to find the technology to attach solar panels directly to the sails in order to have enough surface area to make it economically and practically feasible. Battery technology will also need to be developed which has a much higher watt-hour/kilogram storage capacity so we will also have propulsion at night without weighing the boat down with hundreds and hundreds of kilograms of batteries.

As old as wind power is, its still the best thing going without having to burn fossil fuels.

We just don't have the technology yet. I think we will someday though.
__________________
David

Life begins where land ends.
David M is offline   Reply With Quote
Old 16-07-2009, 10:18   #5
Registered User
 
scubasteve's Avatar

Join Date: Jun 2009
Location: Texas
Boat: Shamrock 246 Open
Posts: 54
Boat engines run at much higher loads then cars due to drag, wind, current, sea state and power loss through the running gear. Not practicle at this moment in time.
__________________
scubasteve is offline   Reply With Quote
Old 16-07-2009, 10:33   #6
Registered User

Join Date: Feb 2008
Location: Cruising
Boat: Jeanneau 38 Gin Fizz- Rhosyn Mor
Posts: 331
perhaps we shall see the day when someone can produce a wind powered boat, wind power is so much more powerful than solar.....
__________________
Rhosyn Mor is offline   Reply With Quote
Old 16-07-2009, 11:21   #7
Moderator Emeritus
 
David M's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: San Francisco Bay
Boat: research vessel
Posts: 10,153
I was thinking along those lines as well but did not want to be the smart alec to say it.

Having both onboard in case the other fails is really the best of both worlds still. Atomic's original question is still an excellent question.
__________________
David

Life begins where land ends.
David M is offline   Reply With Quote
Old 16-07-2009, 11:21   #8
Vendor
 
witzgall's Avatar

Join Date: Oct 2006
Location: Eastern Shore, MD
Boat: Camper Nicholson 44 Ketch
Posts: 1,777
Electric boating is happy and well for many users. If you want to get into the scene, join the Electric Boats Yahoo group.

Concerning a wind powered boat, you already have one. Look up....
__________________
witzgall is offline   Reply With Quote
Old 16-07-2009, 11:42   #9
Registered User
 
AtomicPhil's Avatar

Join Date: Jul 2009
Location: Bronx, NY
Boat: just my arms and legs
Posts: 50
Send a message via ICQ to AtomicPhil Send a message via AIM to AtomicPhil Send a message via MSN to AtomicPhil Send a message via Yahoo to AtomicPhil Send a message via Skype™ to AtomicPhil
Oh thanks for the information. gives me an idea if this works or not. well this site so far has many good infos.
__________________
AtomicPhil is offline   Reply With Quote
Old 16-07-2009, 11:56   #10
Moderator Emeritus
 
GordMay's Avatar

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 31,596
Images: 240
Quote:
Originally Posted by Rhosyn Mor View Post
perhaps we shall see the day when someone can produce a wind powered boat...
Indeed!
__________________
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"



GordMay is offline   Reply With Quote
Old 16-07-2009, 22:07   #11
Registered User

Join Date: Jul 2009
Location: Pacific Ocean, Brookings, Oregon USA
Boat: Coronado 25 (Don't tell her I'm shopping for an upgrade)
Posts: 32
Jeez AtomicPhil, that's a ridiculous idea! Unless maybe you're the guy in this video who demos his sailboat navigating out of the harbor via electric propulsion that's recharged by regeneration, solar, wind, and/or shore power.

Since sailors got along with zero non-wind propulsion up until diesel engines (let's not get into steam) became available in the last 100-ish years, it doesn't seem that unreasonable to rely on wind 99.9% of the time and just using the electric motor to cozy up to the dock. Granted, I'm not usually in a big hurry to get back to the office when the wind dies to begin with.

A quiet boat with one less fragrant, dirty-burning liquid on board sounds like nirvana to me. The battery array required is a definite negative, but I like the trade-off. And... *cough* I'm sure it isn't even close to cheap. (looks like the system in that video is either $3995 or $5494 without the batteries)

Okay, okay... maybe I'm defending AtomicPhil less than I am my own obsession with this technology. You got me.

Wow! That Yahoo group is nuts. Almost 12k posts with almost zero organization of the threads.
__________________
Transforming from urban professional go global adventurer SailToTrail.com and exploring with only human, wind, and solar power.
sailtotrail.com is offline   Reply With Quote
Old 16-07-2009, 22:26   #12
Do… or do not
 
s/v Jedi's Avatar

Cruisers Forum Supporter

Join Date: Feb 2009
Location: in paradise
Boat: Sundeer 64
Posts: 9,198
About the weight of the batteries: for mono hulls, it can be used for ballast when the batteries are put low. We have our house batteries in the keel sump and they are officially part of the ballast.

cheers,
Nick.
__________________
s/v Jedi is offline   Reply With Quote
Old 17-07-2009, 18:47   #13
Registered User

Join Date: Jul 2009
Location: Pacific Ocean, Brookings, Oregon USA
Boat: Coronado 25 (Don't tell her I'm shopping for an upgrade)
Posts: 32
Quote:
Originally Posted by s/v Jedi View Post
About the weight of the batteries: for mono hulls, it can be used for ballast when the batteries are put low. We have our house batteries in the keel sump and they are officially part of the ballast.
Good call.

I referred to the smell and general nastiness of fossil fuels, but I also momentarily spaced out on both the weight and space saved by not lugging around fuel. At 7lbs/gal that can add up pretty quickly if you have even semi-significant tankage.
__________________
Transforming from urban professional go global adventurer SailToTrail.com and exploring with only human, wind, and solar power.
sailtotrail.com is offline   Reply With Quote
Old 17-07-2009, 21:27   #14
Do… or do not
 
s/v Jedi's Avatar

Cruisers Forum Supporter

Join Date: Feb 2009
Location: in paradise
Boat: Sundeer 64
Posts: 9,198
Engine + full fuel tanks is 2.3 tons on Jedi...

ciao!
Nick.
__________________
s/v Jedi is offline   Reply With Quote
Old 21-07-2009, 05:43   #15
Registered User

Join Date: Mar 2008
Location: Akron, Ohio
Boat: Bristol 29(1967)
Posts: 599
Please consider this scenerio . . .

No wind(meaning no wind to motor against)

No speed(meaning 0.0 knots forward movement

Sunny day

Why is it(so it seems), that movement by motor is always considered in terms of maximum speed, or something close to maximum speed?

In this scenerio ANY SPEED would be more than 0.0 knots and many years ago I read a book(don't ask me which), that referred to "natural" speeds of boats.

The "Natural" speed being referred to was the speed a boat could maintain in calm waters on a windless day with "almost" no force being placed against it.

Beyond this "natural" speed, the power curve rose sharply in order to move the boat faster than the natural speed up to the hull-speed, at which time useable power reached it's usefulness.

If I rememebr right the "natural" speed for my Venture 25 was about 1-1/2 knots, or almost 2 mph.

2 MPH is an alfully lot faster than 0.0 knots.

SO, considering the original question, I wonder how much power a trolling motor would draw to move a sailboat at about 2 or so MPH and if that power draw could be sustained by a decent sized solar panel?

Keep in mind that my scenerio involves absolutely dead air and need for very slow speed.
__________________

__________________
SURV69 is offline   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Solar-Powered Air Conditioning ? Target9000 Liveaboard's Forum 52 10-07-2016 12:15
Motor or No Motor for Long-Term Cruising? boatyard Pirate Construction, Maintenance & Refit 41 02-08-2009 22:13
solar 21 just about to be first solar/electric powered boat to cross atlantic schoonerdog Multihull Sailboats 2 07-02-2007 10:04



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 13:36.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.