Divecoz wrote:I've been thinking about this mod as well ( Solar Panels)
I am working through a few issues.. #1. I refuse to have my boat..... look like Fred Sanford's front porch..I know this is a No Issue for some, but I dont want MY Sailboat to look like Fred's porch..
#2. Front mount or Back?
I find no perfect location. For Maximum wattage, ease of mounting and aesthetics..
a. Front bow rail mounting looks pretty good ( Perco Deck Mount Electrical Connections) Both Unit's would swing up from Vert (storage ) to Horz. ( collection ) position.. That one might well Require a long run back to the batteries(?) PITA running wires(?) Voltage Drop Concerns (?) Issue No Issue(?)
b. Another location Is at the opposite end of the boat. Mounted on the mast crutch. Again stored Vert. ( like the rudders on a blow boat )Raised to Horz. position for use.
c. Lastly (?) DaveB's Bimini mount..? aesthetically no one would ever know it was there.. However........
Bimini mount affords the least amount of collection, as I see it , 2 smaller panels?.. Storage issues "seem" the greatest?.. What to do with the panels when the bimini is not in use?..
No matter your configuration choice , the wattage produced is never going to be so much that wiring and connections are ever a real problem as many connections are available, from Marino Perco Blue Sea, even numerous RV suppliers.. All make dozens of connections for a variety of application's and affording as well , numerous price ranges..
Aesthetics to ME... are Very Important and it appears to me a Clean Professional in Appearance , Custom made , 1 off.. Mounting System is going to be the biggest issue..AND its going to cost a few bucks to get it right..
Once you have the collection and mounting issues solved... Storage is needed , and this is NOT the time to go too cheap as well.
Good Quality batteries are Not Cheap and and how many you desire depends on your personal needs .. Quantity of batteries will raise or lower the bar for positioning these units as well.
Divecoz, if you look at flexible solar panels (see my post above), you'll see that prob most of your points will be ticked by them. You really can roll them up for storage and 30Watts is pretty good (and if they work in our crappy British weather they must work even better in the plenty of sun you guys have normally compared to Old Blighty !
FinallySailing: Its the cost of those and the low output even for here.. Even for those down in Sunny Florida..
Just to maintain your batteries or to add a little juice.. that one panel might be fine..
If on the other-hand you desire to be gone a few days or a week or two..and if you desire to .. sail more than motor.. and run a fridge and sometimes an A/C unit.. somewhere close to 200 watts with 4 deep cells is a starting point.. how much would 7 of those units cost?
Divecoz wrote:FinallySailing: Its the cost of those and the low output even for here.. Even for those down in Sunny Florida..
Just to maintain your batteries or to add a little juice.. that one panel might be fine..
If on the other-hand you desire to be gone a few days or a week or two..and if you desire to .. sail more than motor.. and run a fridge and sometimes an A/C unit.. somewhere close to 200 watts with 4 deep cells is a starting point.. how much would 7 of those units cost?
Good point - I forgot you've got all these electricity hungry luxuries ! Not to speak of the space needed for that "solar sail". I stand corrected
A lot of us tinkerers.. have this idea of using a electric trolling motor - hooked to a single battery (Group 27 or so....)... Doesn't take a lot of juice to recharge - but it needs to be a good battery for short term power.
I have liked that Idea of having an Electric Trolling motor ever since buying MY 30 y.o. Evinrude 6HP / BSA outboard for the dink..
BSA stands for Bastxxrd Stopped Again!! It would afford some maneuvering power and could easily be swapped back and forth from The M to the dink..
dvideohd wrote:A lot of us tinkerers.. have this idea of using a electric trolling motor - hooked to a single battery (Group 27 or so....)... Doesn't take a lot of juice to recharge - but it needs to be a good battery for short term power.
The math for using solar to recharge a trolling motor just isn't there.
A 1 HP motor is a 700watt device...to use for an hour of motoring would require a huge solar setup to keep the battery charged, assuming a 12 hour day of sunshine, that's a 240 watt solar cell just for the motor for one hour.
I agree the amps aren't there to use solar for trolling motor batteries. There are sailboats that use electric motors--but just to get you out and sailing---then the motors turn to generators and the turning prop charge the batteries using the energy of sailing. Really cool idea but haven't seen it in an "outboard".... Great job for the tinkerer! I had a starter motor on a lawn tractor once that turned into a generator after the tractor started...so it's possible. If you figure it out, let me know! My 65 watt solar panel is just not enough keep up....but if I could drop a trolling motor in the water when the wind is pushing me along and charge up the batteries--that would be great!
(on edit: Here is a link, but you have to be smarter than I am!) http://tinyurl.com/33s8j
SILK
There was a recent post (failed to find it again) that showed an integrated electric outboard and battery. Their site showed a product range covering small tenders to substantial hull size at, I suspect, an above average price level due to the claims and novelty of the products (large lithium batterys - high efficiency electric motors). Still - when you consider you don't have to disconnect and manhandle a separate battery, as well as the motor, aboard your tender for a fairly short duration of charge the idea maintains some merit.
As Catigale points out, the math - given the present state of the art (and the esthetics of hardware location) means either type can't be used in an on-demand basis unless some other form of power collection is added to the boat and even then husbanded resources will still be the order of the day. Not that there's anything wrong with that approach but spontaneity goes out the window!
I'm as green as the next guy - maybe more - but even a very small gasoline kicker (4 stroke) running on the same product I store for my big outboard can probably beat the pricing total of either of the above two solutions, as well as run all day on a couple of litres. I can borrow/buy/siphon some gas if I get stuck somewhere but I would sure be in the muck if I tried to find a fast charge.
That all being said - some form of solar collection and above average storage on the main craft is indispensable for extended time aboard. Don't want to be one of those 'generator all day' guys like I moored next to, last week.
Catigale wrote:The math for using solar to recharge a trolling motor just isn't there.
A 1 HP motor is a 700watt device...to use for an hour of motoring would require a huge solar setup to keep the battery charged, assuming a 12 hour day of sunshine, that's a 240 watt solar cell just for the motor for one hour.
This really depends on your usage. If you can charge for five days and motor for eight hours, you'd be fine and this is really just a question of battery capacity. For a typical weekender, it may work just fine. For a liveaboard or a cruiser, definitely not.
Motoring for 8 hours on a 1HP motor, with 8 group 24 batteries...hmmmm...not my cup of tea...
The numbers give you an idea of the incredible amount of energy content in a gallon of gas and how difficult it is to replace it with direct electricity,
I am thinking more ....for the dink...motor to shore have dinner / beers and motor back.. Maybe that one bad docking attempt I had I could have used it to hold me against the dock??? I didn't dare leave the engine running and try to tie off. I think (?) I could over power a trolling motor pushing a boat as big as ours??
No doubt ya need enough power for the dink but not so much consumption or usage that your draining a battery even every two days.
I bought the Harbor Freight 45W solar panel deal they had last year. It is three 15W panels. I use two of the panels on rods that attach to the cabin top stanchion bases, one on each side. They fold out like wings and pivot from the vertical to down almost touching the cabin windows. They can be adjusted from full down to full up in less than two seconds. This allows me to angle them so that they are almost always facing the sun. I figure that gets me a lot more power than a flat, stationary panel or one that is difficult to adjust.
For wiring, I connect them thru the mast light connector. I do not use a controller so the mast light switch allows me to disconnect them from inside at night. At anchor, I adjust them to where I think the sun will be in the morning. When the sun rises and the panels begin to work the mast light switch light begins to glow as they put out power. When it gets bright red, I turn it ON and the panels are working at maximum first thing in the morning when the sun is still low.
They are generally very stable, even in high winds. To protect them from flopping over onto the cabin top and doing themselves harm, I lay a boat fender along the holding rod. If they flip, the fender catches them without damage. For transport, just four ball bunges make them simple to remove. I wrap them in an old blanket and they are ready to store.
I don't think they satisfy all my needs. With an electric reefer and an autopilot I use a lot of juice. I have two big AGM batteries and the panels, along with the engine, allow me to stay out as along as I have needed, so far (max eleven days, but hoping for more).
