What form of energy?

[sedentary]

Originally Posted by TacomaSailor

"By my estimate, 750 watts of solar should be right for a boat with a small 12VDC chest type fridge and a reasonable autopilot. that's 3 fixed 250 watt panels, and you'll want a combined MPP charger/combiner/inverter that'll put you back a few boat bucks."

I think you may overstating the required power from the solar panels.

We've had 500 watts (4 x 124 watts) for 15 years. While cruising full time for three years in the Sea of Cortez and as far south as Zihuatanejo we never once had a problem keeping the batteries (2 x 8D Gellcells) fully charged.

We have a 12V BD50 refrigeration compressor and a Spectra 380c water maker (17 amps at 13.8 V = 16 GPH water) and a Raymarine ST6000 / 12V Type 1 Linear Drive autopilot.

The batteries were always full charged by 2 PM and we could then run the
Spectra, the BD50, and still put an amp or two into the batteries from 2 PM to 4 PM.

We made no effort to reduce our electrical consumption ' cause the solar panels make so much excess power.

The longest we sat on the hook without starting the Yanmar was 22 days - all power delivered by the sun.

And, we have just a old "dumb" Trace C-40 controller circa 1999.

As far as Honda 2000 or other gas powered generator - we made those boats anchor 50 yards down wind to reduce the noise pollution.

I think 750 might be a bit much too. Even 500 seems like more than I would need. Not sure I need to get a really good idea of power usage and what I expect the future needs to be. Maybe AC a bit later. How did you mount the cells? Any pics of the mounting? Good information. thanks.

[sedentary]

Originally Posted by nimblemotors

Doesn't this boat have an engine with an alternator?

It does. Which is fine when motoring but I think the gas usage is better on the generator than it is running the engine. It's an atomic gas engine. Not as good usage compared to diesel I hear?

[scottmills]

I get by with a mere 160 watts.

[sedentary]

Wow! Such an active group. I love how I can ask a question and actually get good and useful advice. Thanks to everyone. I think I'm doing to do this.

Wait.

I'm going to be motoring for quite a bit of my trip which will keep me topped up. Then, as a lot of people advised, I'm going to get to know my ship and power consumption. The more I read the more I'm agree with the advice here. I like the silence of solar and it would really affect the enjoyment of a quiet anchorage.

I think this has been an incredibly helpful posting and I thank all the people who contributed. I feel much more confident now than I did at the start.

Regards,

[onestepcsy37]

Originally Posted by secrabtree

I don't understand the "If you have the house battery capacity" as regards solar. Why should solar require any greater battery capacity than any other battery charging system?

If your ONLY charging source is solar, you will be living off your batteries maybe 2/3 of the time, so you need enough amp hours to run your boat without dragging your batteries below the dreaded 50%.

The OP's question was which ONE of the choices he presented was best in his case. I have both solar and a honda 1000. And a 550ah battery bank.

[Cheechako]

Hi amp alternator and the Honda. Unless you sit for very long periods without moving.