Solar Panels

[Phillip]

Hi Everybody,

Can I enquire as to what solar panels are being used out there and as to their success in maintaining batteries under cruising conditions [not on a mooring/marina!].

The questions I have are:
1. What size, that's wattage? [I'm looking at around 100watts]
2. How many house batteries and total amp hours do you have?
3. What is the recovery rate? ie maintains batteries during use or requires a day or two to recharge.

Before anybody asks, I'm running a starter battery [dedicated to starting the inboard] and two 120Amp Hour house batteries. My consumption includes; ST1000 Autohelm, VHF radio, am/fm radio, chartplotter, 2 sounders and all my lights are LED. All of these are running when sailing. I'm not running a frig, nor am I likely to do so in the future.

Looking forward to the answers.

Phillip

[RodM]

Hi Phillip, On my Manitou (Just sold, Top Hat on the horizon) I've run a 100 Watt Solar panel (50 X 100cm) via a Morningstar 6 amp solar controller with two 140AH marine gel batteries, one for engine & other as house battery.

Today in Manly (Qld) in full sun, panel was providing 2 Amps power. Covered panel, turned on Nav lights, gps plotter, sounder, fm radio, vhf, attached autohelm, plugged phone in the dc charger and was draining 5 Amps. Making the autohelm work would increase that drain to 6 Amps. This system has an Amp meter so you can easily see 'current' use.

I usually sail with only plotter, sounder, sometimes autohelm & radio, basic lights at night. In sunny weather batteries stay charged even over 3-4 days varying use - my boat's also got (had) an electric water pump and macerater head. On cloudy days, and especially if daughter decides to charge her laptop a couple of times, I'll need to start the engine for an hour or so each day to keep the battery charged.

I've found the solar system works great... while the sun shines. Even when overcast it provides 24hrs + power, more than enough for weekend sailing.

Hope this's helpful,

[Troppo]

I don't know what my solar panel is but mid-day on Gold Coast a few weeks ago, it would output 2 amps. Could be 100 watt. Battery is one only at 100 amp/hr. Since I used the motor most days when I travelled up the coast, I can't say what the drain was like if I was just sailing. However, at night using cabin light and 'netbook computer (12v charger not 240 via inverter) and sometimes chartplotter (planning next stage) and mobile phone charger (12v) and anchor light, the battery would only drop down to 90% or 80% if that and would easily charge up again the next day.

Trapped at anchorage at Mooloolaba with a week of rainy windy weather, the battery did not get below 75% as there were occassional bits of sun and I did not allow much power drain. I could have used more but I was unsure how the system would go since I am new to the boat. Didn't need to worry, plenty of power.

On this system, there is plenty enough capacity for my basics for 4 or five days heavy cloud, even more since I could take it down to about 50% charge without too much drama. Once the sun is out the panel outputs more than I use in a day so the battery charges up.