Tuesday, August 31, 2010

Solar Skiff Early Observations

(CJM pics)

Mostly qualitative and maybe a little quantitative…Please remember that the data collection has just started.

My first comment is that I inadvertently built a solar powered ice-breaker! Not in the polar sense, but most definitely in the social sense. It’s always been one of my favorite parts of cruising to wander aimlessly about the anchorage and chat around sunset. And I have no aversion to responsible sundowner consumption. But the truth is, it’s not always easy to engage in conversation with folks you don’t want to disturb. Circe has solved this problem. The interest and enthusiasm expressed already has been wonderful. Kids, particularly, seem enthusiastic about what they see. This is encouraging, and I try to make the point that they see only a seedling sprout that their generation will nurture into things we cannot even imagine. So maybe after all these years, the urge to learn to farm is fulfilled from a different angle.

The reactions to date seem to fit into 3 file folders.
(1) There are, as there will always be, the totally unimpressed. No, solar skiff does not plane (except under tow.) Yes, that is as fast as she goes (3.5 knots subject to later prop pitch experimentation.) I was a bit taken aback at the first unimpressed reaction coming from an 18’ catboat sailor though…”Who you callin’slow??”
(2) Then there are the incredulous. “Does that really work?” is their mantra. To date, my retort has been “You see it.” Though, I am thinking about concocting a story about a trained team of bluefish in harness for these folks. The fact is, The battery bank that drives this boat has never been charged by any means other than the 90 watt solar array. I guess I have run some 30 to 40 hours so far. Good that it’s been sunny!
(3) The reactions that make it seem worthwhile are the enthusiastic ones. If something can be demonstrated on a small scale, it will create belief in what can be done on a larger scale. I don’t deny that alternate energy is still about bending over to collect pennies, but just so, 100 of those make a dollar.

On the equipment side, I am so far on voltage regulator #3, motor speed control switch #2, circuit breaker #2, and ammeter #2. The voltage regulators packaged with the solar panels seemed to be black boxes full of pretty beads. They simply never worked. It wasn’t a rating or a connection issue. They were just junk. The SunSaver presently installed is correctly keeping the batteries at a bank voltage of 14.4 or below. I may eventually install a bypass switch for a now-and–then 15 volt blast charge to clean the battery plates, but that will be a winter project. The used trolling motor was less gently used than I hoped. The switch was crunchy and intermittently dropped out of the highest speed setting from day 1, so I had a replacement switch on order from Minn Kota when it eventually smoked (literally!) I got a humble pill when a gas dinghy passed and I thought – “Wow what stinky exhaust. Huh it’s lingering. Smells more like plastic. Whoah- there’s smoke coming out of my motor switch!” Still got back to Charis at low speed, so the oars remain unused. The circuit breaker was upgraded from the original 50 amp rating at the recommendation of Minn Kota. The ammeter replacement was prompted by a short lived attempt to power it with a non-isolated power transformer. Electronic optimism ends abruptly when smoke appears. At present we are all-systems-go.

The slightly numerical observation to date is that I have run at full speed for up to 4 hours at a stretch (subject to social stops) with power to spare. Recovery time varies with use and sun strength, but so far I have had no problem enjoying harbor cruises and my short daily commute on a break even basis. Actual numbers are being logged and will be compiled when there are enough of them to make sense of.

On the qualitative side, the most commented on feature of the skiff is that it is silent. I did a dumb thing to test how silent. One evening I watched two outboard dinghies approach (at a respectable distance) an osprey nest on a pole. The residents sounded their dissatisfaction when they were each at least 20 feet away. I got much closer, but realized then that sneaking up on a sharp talon bird of prey is not hugely brilliant. Since, I have limited my bird stealth to cranes, herons, gulls and such. Because I can sit very still, I find I can approach closer than even in my kayak. This brought about an interesting epiphany for me- That noise is pollution too. In truth, I already felt that way, but I guess I just never put silence on the goal list for this project. Bonus. Next to be noticed are the panels themselves, followed, I would say, by my choice of a fairly traditional Whitehall hull shape, and a rather pretty one at that. Since her hull lines are not mine, I am not being vain. I read once that a good boat cannot be walked away from without at least one back glance. Circe has that going for her.

Rigged for towing....

(Photos by Gavin Ashworth – NYC)

1 comment:

  1. Excellent report - and I really enjoy your writing style and philosophic observations. Yes, noise is pollution too. And in some sense so is "disturbing the birds" (or the fish, or the Orca.)

    I can't count the number of times slip neighbors have said "Gee, I would have offered to help with your dock lines if I had heard you coming. Boy that boat is silent!"

    On SUNDANCE we can basically get a weekend of motor use (which is limited to a few miles range, getting to the sea buoy as it were) out of a week at anchor on the solar panels. And this on a 36V/15000 lb boat.

    I look forward to more reports!

    Chris McKesson