Wednesday, 2 November 2011

Free energy (ish)

There has been a rash of solar panel installs along our moorings. I had been mulling over the benefits for some while. I can understand a liveaboards opting for them but for  a casual use boat like ours??

One thing that was getting to me was having to run the engine before we left so the batteries were topped up, normally after our last night aboard. This just seemed to waste diesel as well as the lovely tank of hot water ! So I got to thinking how good it would be if we could walk away from Waterlily after a nights use of power and come back next time to a fully charged up bank of batteries, almost magic.
So I talked to my fellow moorers, talked to Shobnall and did my Internet research. I came close to buying from Andy at Shobnall but was a little put off over his answer to my question regarding MPPT v's PWM controllers. As I intended to have this panel for some time I wanted to get the most from it. I also read that PWM controllers were not giving the smartgauge 100%. I don't pretend to understand much of the jargon but I was sold on the fact the MPPT types get more out of the panel and into the batteries - simple decision then.

I opted for a 135w Kyocera panel and a sunsaver MPPT from Midsummer They were very efficient in the delivery and did not charge extra for the longer cables I ordered.

I did not want to drill my roof..... and was not too bothered at this time about angling the panel. I did want to be able to remove it for maintenance so I opted for taxi sign magnets from EBay (guaranteed upot to 70mph ??). Perfect fitting and I have it protected from theft with a very able cable lock drilled to the plank holder.

I did the install myself in a couple of hours. I left it just completed and was really pleased to come back 24 hours later to 100% on the smartgauge. It is great when a plan comes together.

In fact we have been on board three or four times now and not run the engine. Last time we lit the stove and had tepid water as well. I expect we will run the engine for its own good and to give us hot water but once we have a tank full I am hoping the stove will keep the water hot via the new calorifier I fitted a few weeks back.

A few bad pics as it was getting dusky when I took them. One thing I am impressed with it how little light there needs to be for a charge to go into the batteries. The controller has quite a few useful settings to support the batteries and it also has an RJ11 socket that allows me to collect 30 days of data off the controller as well as dynamic data if needed. Needless to say I have done the connections adn will post some stuff later on its performance.


Andrew Denny said...

Nev, one fellow in London has a boat powered and driven entirely by solar panels (except for space heating).

And he has an interesting point: He sticks them on the SIDE of the boat, because (he says) the light bouncing off the water is almost as bright as the sun itself.

No one else does that, as far as I can see. Of course, you have to have a more south-facing aspect, and it doesn't work for every situation. But I've never seen anyone else mention it.


Nev Wells said...


Neither have I. I know some on my moorings have them tilted to they can follow the sun. My regulator allows me to record info from the panel so I'll be investigating that soon.

One thing that could be worth a follow up is the lack of support for instals or feed in tariffs for boats. After all I am not running my engine as much now saving energy, if I were a home install I'd be getting income from the government for that - maybe a WW article?

Take care