The thing with solar is that it is changing almost daily. One persons comments about optimal conditions just isn't the case anymore.
We just installed 3 Xantrex 220W Flex panels on our Albin Trawler using our Hard to Top over the bridge as the mounting platform. We are currently in an open slip with covered slips on either side of us.
From the day after the panels were installed we have gotten 400 to several days ago 650W of power from the panels (my Victron MPPT charge controller tells me the wattage brought in daily), or currently. On a day of rain & overcast the panels generated @ 500W of power.
Solar is not a standalone solution.
Alternators are only useful when the engine is running and who wants to run their engines or generator to suppliment their battery charging while at anchor (those around you don't)? Your house bank is an intergral part of shipboard power and that should be balanced with alternator output while running to get a good charge on the batts (3 step charging is very important) as well as the inverter you are using (generally the higher the wattage of inverter the better).
As to onboard generators, noisy, smelly and obnoxious are not generally looked on favorably by those around you. You want to run your AC get a better AC system and a bigger house bank or open your winows and let the breeze in, you are at anchor.
I am considering a fuel cell to suppliment my off-grid power. A fuel cell linked with my inverter autostart will fill in the gaps of power production and not add any noise, smell or other obnoxious elements to our anchoring.
Watt in PA is building a fuel cell which uses propane as the fuel source. NO noise or smell from its generating. Efoy uses methane which is purchased from them.
IF you are considering solar, contact Jim Light at eMarine or Katie & Lyall from Sun Powered Yachts and get help in building a system for your boat.
m/v Nepidae, Albin 43 Sundeck