International Telstar Owners Association

I noticed from looking at Trina's blog that you have dual solar panels mounted on Trina's coach-roof. How about some details?

Lou Giansante

When you get back from camping!

My guess would be about 80 watts total, as those appear to be the semi-flexible amorphous silicon panels, not the rigid ones.

Thanks Dan,

I read your primer on solar. Nice work. The motor I'm putting in the boat has pretty good charging power. I would like to supplement it with panels to keep the battery charged while on a mooring and, at the very least, keep a small bilge pump working between sails. I'll probably be mooring the boat on the Delaware River near my house next spring, to shake it down. Then, I'll take it to Cape May, where there are good moorings available. So, I doubt that I'll be keeping the boat near shore power.

I really liked the look of Alex's panel installation. You could probably get close to that look with flat panels and get a lot more power.

The problem with Alex's layout, if you go with poly/mono-crystalline panels, is that you can't step on the panels and the panels are far more affected by shading than amorphous thin-film panels are. Many thin-film panels are durable enough that they can be walked over with care, which is not the case with the rigid poly/mono-crystalline glass-covered panels.

BTW, over the winter, I found that a 25 watt mono-crystalline panel was enough to keep the batteries topped off, even with the occasional uses of the stereo and cabin lights. With my boat on a mooring this past season, I've found that the 25 watt and an 130 watt panel keep the batteries pretty well topped off, with the refrigerator running 24/7. That is fairly impressive if you consider how rainy and cloudy this summer has been up in New England. My plan is to have two 130 watt panels, one to starboard and one to port, and one 25 watt panel over the stern arch.

luigisante wrote:Thanks Dan,

I read your primer on solar. Nice work. The motor I'm putting in the boat has pretty good charging power. I would like to supplement it with panels to keep the battery charged while on a mooring and, at the very least, keep a small bilge pump working between sails. I'll probably be mooring the boat on the Delaware River near my house next spring, to shake it down. Then, I'll take it to Cape May, where there are good moorings available. So, I doubt that I'll be keeping the boat near shore power.

I really liked the look of Alex's panel installation. You could probably get close to that look with flat panels and get a lot more power.

Dan wrote: I've found that the 25 watt and an 130 watt panel keep the batteries pretty well topped off, with the refrigerator running 24/7. That is fairly impressive if you consider how rainy and cloudy this summer has been up in New England. My plan is to have two 130 watt panels, one to starboard and one to port, and one 25 watt panel over the stern arch.

Dan tell me the kind of refrigeration you have and give me all the details you can. I am impressed you could run it with just solar.

Pat

The refrigerator is an Engel 27MT unit. It was installed on my boat by PCI, and can run off of 110 VAC or 12 VDC. The thermostat can be set from 0-5. At any setting over 1.5—it acts as a freezer for the most part. I usually have it set at 1-1.25 and the drinks are very cold... and frozen steaks take over a day to defrost. BTW, the Engel and Norcold refrigerators have consistently been ranked as excellent by Practical Sailor magazine—Engel and Norcold are both made by the same company and sold under different labels.

Pat Ross wrote:Dan tell me the kind of refrigeration you have and give me all the details you can. I am impressed you could run it with just solar.

Pat

I agree. I have the same refrigerator and it is very efficient, using very little amps/hour. They are well made and I installed my initially on hte port side of the boat but have since moved it to starboard on my setee to hard wire it right to my control panel. The picture below shows the old position.

gary g.

I've been giving this solar panel thing a bit of thought and it occurs to me that my Teslar (Mark 1) will have quite a bit of unused deck space on the ama decks, in addition to some space on the coachroof. In all, I think I can put quite a few of the less expensive, flexible panels in places where the breakable type of panel would clearly not work. I was researching on-line and found a 64 watt unit that was both affordable and would fit on the deck along with a smaller 40 watt unit made by the same company. I could add 2 - 40 watt units to the coachroof with a charging capacity of 288 watts.

The question, I guess is, will that be enough. I have been using the amps x volts = watts formula to try to back out some estimates of capacity, etc. and it looks like such an array would be sufficient for my uses. In designing the engine compartment to accomodate the Rotax jet ski engine, I installed a water-tight bulkhead between the cabin and the engine compartment. The cabin is serviced by a whale manual pump that can be operated from the cockpit. The engine compartment, however, will have its own bilge pump (probably a small one like a Rule 1200). The engine starter works off a small 12 volt motorcycle battery and i intend to have another battery for the boat's domestic system and running lights. I want to store enough capacity to sail at night without having to run the motor too often. I was thinking that a single 220 amp battery should do it (is that the capacity of Dan's golf cart batteries) with the smaller 12 volt battery isolated by a switch and reserved for starting the engine. Anybody use higher capacity batteries? From what I can see, they get heavy as the amperage increases and I am trying to keep the weight down on my boat.

I would be interested in pictures from those of you who have already set up solar arays as well as battery set ups. I am thinking about putting the starter battery in the engine compartment and the boat's system storage under the cockpit in the main cabin. Thanks.

Lou Giansante

luigisante wrote:I've been giving this solar panel thing a bit of thought and it occurs to me that my Teslar (Mark 1) will have quite a bit of unused deck space on the ama decks, in addition to some space on the coachroof. In all, I think I can put quite a few of the less expensive, flexible panels in places where the breakable type of panel would clearly not work. I was researching on-line and found a 64 watt unit that was both affordable and would fit on the deck along with a smaller 40 watt unit made by the same company. I could add 2 - 40 watt units to the coachroof with a charging capacity of 288 watts.

The flexible panels may be a good choice for you, especially if you want to surface mount the panels. The amorphous thin-film panels you will be using are far more shade and low-light tolerant than poly/mono-crystalline panels would be, but will require far more surface area.

The question, I guess is, will that be enough. I have been using the amps x volts = watts formula to try to back out some estimates of capacity, etc. and it looks like such an array would be sufficient for my uses. In designing the engine compartment to accomodate the Rotax jet ski engine, I installed a water-tight bulkhead between the cabin and the engine compartment. The cabin is serviced by a whale manual pump that can be operated from the cockpit. The engine compartment, however, will have its own bilge pump (probably a small one like a Rule 1200). The engine starter works off a small 12 volt motorcycle battery and i intend to have another battery for the boat's domestic system and running lights. I want to store enough capacity to sail at night without having to run the motor too often. I was thinking that a single 220 amp battery should do it (is that the capacity of Dan's golf cart batteries) with the smaller 12 volt battery isolated by a switch and reserved for starting the engine. Anybody use higher capacity batteries? From what I can see, they get heavy as the amperage increases and I am trying to keep the weight down on my boat.

I would recommend using a small starting battery, and then have two 12 VDC house batteries to give you a house bank of about 200-250 amp-hours. The two smaller batteries are far easier to install and give you a bit more flexibility in where you can install them. Lifting a 70 lb. battery is far less a strain, especially given how you may have to bend/twist to get it into place, than trying to do so with an 140 lb. battery. Between the solar panels, I currently have a 130 Watt and a 25 Watt solar panel mounted on the boat, and the batteries, I have two 6 VDC 225 amp-hour batteries for a 225 amp-hour house bank and a small 35 amp-hour starting battery, I can run my refrigerator and the lights, stereo, radio, etc....

I would be interested in pictures from those of you who have already set up solar arays as well as battery set ups. I am thinking about putting the starter battery in the engine compartment and the boat's system storage under the cockpit in the main cabin. Thanks.

Lou Giansante

I would avoid putting the starting battery in the engine compartment as the heat will reduce the battery's life and charge capacity. Batteries generally do better in cooler locations. I'd also point out that multihulls, generally, do a bit better if the weight in the boat is very slightly aft-heavy.