effectiveness of solar & wind

[Giulietta]

Originally Posted by PBzeer

Giu - not many people seem to comment on the blogs. Don't know why, just seems they don't.

Pffff that's because they either can't read...or can't write

[CosmosMariner]

Originally Posted by camaraderie

Cosmos...Good post with a real world example. I don't think that ANYONE is suggesting solar doesn't work. Only that you can't get more than the rated power out of a panel no matter what you mount it on.
225 watts of fixed panels should be capable of generating an average of 50-60 amps a day which is plenty to run a modest cruising boat. The Bahamas give a lot more sun than a lot of other locales so adding the wind vane is a good idea for his future plans. My own experience was that a wind vane in the Bahamas actually gave me more amps than my 160W solar array...but that was in winter so in summer I might not have gotten much from the wind.
Is he planning on a Cat27 circumnavigation??? What is he going to do to beef her up?

Thanks for the kind words. I try to stick to the topic at hand and as the Native American Chief said as he was being sworn in to testify before Congress, 'I can not tell you the Truth, I can only tell you what I know.' By the way, I don't question the fact that if you can keep the solar array at right angles to the sun you will 'maximize' the production of power. In my experience though there isn't enough of a difference to make it worth my while to install an auto tracking system or to move the array manually on my boat or my house. I have tracked power production by the hour at my house and calculated the performance %. From sun-up to sun-down there is a hperbolic curve of almost even distribution from 30% to nearly 70% back to 30%. Total for the day is more than I use so I see no need to add an auto tracker. Same is true on my boat 'Wu-Hsin'.

When my son makes the next trip he will be doing it in a different boat. He is currently looking for a seaworthy design in the 32 - 37 ft range. Any structural modifications will necessarily depend on which boat he buys. The 1979 Watkins 27 he made the Bahamas cruise in was a little light in his opinion even though fully loaded she displaced approximately 10,000 lbs. He spent one night off Cape Fear NC in 55mph winds and several days in various places where wind and wave action moved 'Walkabout' around more than he liked. So he wants more design displacement and a little more water line length to add to the 'comfort factor'. While he has grown up on my boats and is a fine sailor I suggested he get some 'in command' time under his keel to determine what he likes/what works 'for him'. This past trip was a great success for many reasons. He not only got to try out his theories and assumptions but gained alot of perspective from the other 450 boat crews in the harbor in George Town Exumas where he anchored for 2 months. The most common non engine driven recharging systems were solar and wind. Types and brands varied and mounting systems varied also. I spoke to him today and he confirmed that he will go again with solar panels probably 3 130 to 150 watt (rated :-) ) fixed mounted because of their simplicity of design and nearly zero maintenance with no moving parts. He was advised by sailors with both wind and solar that when they were in the doldrums or in windless weather patterns for 7-8 days or in winds too light to generate power, solar was their savior. He himself observed several days in George Town between March and May that the normally constant Trades didn't blow and the boats that only had wind generators had to run engines. So the combination of wind and solar will cover all circumstances he is likely to encounter. He will also replace lights with LED versions because of the low current draw. He will be factoring in the load of a SSB as well.

CosmosMariner

[sailingdog]

Cosmosmariner-

Have a couple of good suggestions for boats for your son to look at, which were from a post on another thread:

If I were you, I'd be looking at the Elizabethan 33, Southern Cross 35, Hallberg Rassy Rasmus 35, or the Alberg 37 (which came in yawl and sloop rigs IIRC).

Note, that these are just a few of the boats that would be good candidates for your son. I'd also add the Contessa 32, which is a rock solid boat.

I'm in the process of converting all the lighting, cabin and nav, over to LEDs right now. The SSB isn't all that much a load, until you start transmitting. In receive mode, most are fairly conservative in their energy use.

[tenuki]

Sort of off topic, but just feeling happy that in today's age of long commutes, jet travel and sci-fi extravagance some people are turning off motors.

[CosmosMariner]

Sailingdog, Thanks for the leads, all sound good but are out of the price range. Southern Cross 31 and 35 would do fine if he can get a deal on one. Assuming the boat comes with no equipment on it his must have short list starts with solar panels, wind generator, SSB, Sextant, GPS. So he can put most of the money into the boat itself. Contessa is rock solid but too 'wet' basically a folkboat on steroids

[sailingdog]

Good description of the Contessa...and accurate too... What's his budget??? If you give me an idea... I'll make some more suggestions...

[CosmosMariner]

[QUOTE=tenuki]Sort of off topic, but just feeling happy that in today's age of long commutes, jet travel and sci-fi extravagance some people are turning off motors. [/QUOTE

Yup! That's why we 'sail' not 'power'. Auxilliary powered Sail boats were the first Hybrid vehicles. However just because I'm out on a sailboat doesn't mean I'm out of the 21st century. I like the modern electrical aids to living but first consideration has to be given to the Sea. 'The Ocean is not inherently malevolent, just very unforgiving.' You cannot negotiate with or Bulls**t the ocean. That's why I go with the simplest systems I can because they will all fail in the marine environment. I could go without any electronics and be happy. In 4 years in the Navy I learned that heat and humidity are the enemy of electronics and where I want to sail there is plenty of both. I also learned that the law of conservation of matter and energy still applies and you cannot get 100% efficient conversion of sunlight to electricity or wind or any other energy source. So i go with the ones that make sense for me and try to keep it simple.

[wind_magic]

Originally Posted by camaraderie

Cosmos...Good post with a real world example. I don't think that ANYONE is suggesting solar doesn't work. Only that you can't get more than the rated power out of a panel no matter what you mount it on.

Hey cam, just a fun/picky technical point, you can actually get more than the rated power out of a solar panel. One way to do it is to put the panel under a giant magnifier and focus a larger area of sunlight on it.

[CosmosMariner]

$20 - 25k.

[CosmosMariner]

Wind magic, that's what I mean about the ocean you can't get nitpickey. But a good point...what are the factors in the rating of any product...have to knoe them or its apples and oranges.