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2011-08-20

And that's how the "Solar Stik" was made obsolete


A few years back, a company producing a solar panel mounting system called "Solar Stik" came in for some good-natured ribbing about its claims of maximizing solar panel output, which is often sub-optimal on boats due to angles and shadows from masts, etc.

Many solar-panel-equipped sailors, of course, have made for themselves various methods to optimally angle their expensive panels. It's not rocket science, after all: The "smartest" mount would track the sun all day, as the "equatorial mounts" on the better sort of telescopes move to keep a given celestial object in sight for long photographic exposures. Even better would be a way to tilt the panels relative to the sun's height, which varies with the seasons, and would make the tracking at the constant right angles at which most (but not all) solar panels produce the most amps.

Some people, of course, just bolt panels for "morning" and "afternoon" on their cabin sides, or on the lifelines when conditions permit, and accept that 1/2 of total output is better than a kick in the diesel tank.

This kid
decided to approach the problem using 800-year-old mathematics and by observing the growth of trees. Perhaps the key to fostering genius in the young is keep from them what is considered impossible. The Fibonacci sequence is, like Fermat's Last Theorem and Pythagoras's Famous One, among the oldest notions in Western math. And yet this young fellow figured out how a tree was better than a solar array when you don't have 300 acres of desert to lay it out in.

So, he may be onto something, but whether it will find application in the way sailors use solar energy remains to be seen. "Sun Tree on the stern? Sure!" One wonders if very light, flexible panels could be hoisted partway up the mast without coming apart in the wind, or maybe another solution would be to make flexible panels part of the mast itself.


4 comments:

SIlverheels III said...

Aside from attempting to aim your vessel's solar panels at 'ol SOL, there are important mounting considerations.

Vessels at anchor swing around constantly. Folks we see with tilting panels are often off the boat while the panels are pointing the wrong way.

Tilting arrays, panels on lifelines and solar trees are at considerable risk during squalls. The aerodynamic lifting properties of a 185W solar panel are quite considerable.

Our 440W array is mounted just off horizontal to prevent water pooling on the surfaces. These panels have substantial fastenings to hold them down.

Centre cockpit boats, ketches and yawls generally do not have large shade free areas (plenty of boom shadows) for mounting solar panels horizontally. In our view, solar panels on the rail are subject to wave or mechanical damage, or hide in the dodger/bimini shadow.

We're very happy to have chosen an aft cockpit sloop. We have a large shadow free area over our bimini for our four panels. Mounting panels on davits is also possible but would be a head bang for us.

Rhys said...

Very true. Having had to physically restrain a rail-secured solar panel during heavy weather on an Atlantic delivery (and being happy to have a jackline in full effect during), I realize the issues involved.

Our 4 x 135W array IS the bimini, although it will require some modification. It's rivetted to steel tubing custom bent for the purpose. While we are going to get mast shadow, it's aft of the boom and comprises an arch of some 15 degrees. This will, we hope give us both shade and power for somewhat longer than just putting it on the pilothouse roof.

The final arrangement won't be done until I have the entirety of the charging setup working and the mast is in, along with the mainsheet. I have already determined that I want some supplemental supports for the arch, which is, while quite strong, probably not so secure at present that the wrong wave or the wrong gust couldn't do it a mischief.

Thanks, Ken!

Benners Adrift said...

As elegant as the Solar Stik is the price is heartstopping. Most of us use a Chevy type solution to bad angles and just buy one more $250 solar panel. Power generation on Meredith is an industrial function and subject to the laws of economics. We just could not afford the elegance (and we don't mind having a backup solar panel)

Rhys said...

I agree, Bob. We are using our four panels as a bimini with a water-shedding camber. Gives us the advantages without getting "stik-stuck".