Just a thought: Has anyone looked at using a plug in solar panel - they are in the news big here in NY as NYC is considering allowing them for apartments -and just plug one into an AC plug on the boat? It could then be used to charge the batteries through your battery charger. I am suspecting that those types of units will drop drastically in price as they become a more common purchase for apartments, etc. And the installation is much cheaper - tie it down and plug it into the AC side of the electrical system.
Good question. Worth looking at… my first question is do they have MPPT or PWM controllers on the DC side.
If you plug one into your boat while the boat is still connected to the marina, and then an electrician shuts off the power to the dock for some service, you could electrocute him/her. Or at the very least, cause them a lot of trouble figuring out who’s boat to disconnect before they can safely work.
Plug-in solar systems come with a microinverter that has anti-islanding logic. ( example here ) . They could be “safe” for the local power system.
I did some reading and concluded I would not use this kind of pugin solar device on Soave. Soave already has batteries. With basic charge controller, I could use off-the-shelf panels to charge the batteries. A good charge controller costs less than the micro-inverter. Plus it’s more efficient to skip converting to AC.
No doubt we’re on the cusp of some really exciting developments in power systems. Very interesting to watch ideas being tested.
Finally someone is asking about a subject I know a lot about.
I was actively engaged in solar business since 1985 and I have installed hundreds of systems.
In my opinion plug in solar is nothing more than to make someone feel like they are doing something to “reduce” their carbon footprint. The reality is that 500 watt panel alone, most plug in is 3-400 watts, will maybe supply few percentage of the total consumption. The idea with plug in is that IF millions of people hung plug in solar over their balcony MAYBE collectively less power needs to be generated.
As for technology itself it is producing AC with built in inverter. The inverter is supposed to be built to UL 1741 standard which says if AC connection must be present with grid power AND if that power is lost on the grid side the inverter is built to shut down within less than three milliseconds. That’s the standard for all GRID tied solar systems.
For sailboat power source unless you are at the shore power plug in solar panels will not work. Normal DC producing panels with a charger controller output to the battery is the only choice.
Good point Naoto !
I failed to realize the anti-islanding logic makes plug-in solar a non-starter for a boat on a mooring.
Good to have seasoned professionals on board.
Thanks,
Rob
My mistake, too. I thought we were talking about a system which could feed AC to the boat when it was unplugged from shore power. Such a system would be dangerous as I mentioned. An anti-islanding system would be safe for shoreside electricians, but would not provide AC power to the boat when away from the dock.
Hmmm. Now that Naoto has outed himself, I wonder what other way we can pick his brain… 