Re: How do you store excess energy?
My solar generally goes into "trickle" mode about 11AM. I doubt that it produces enough to operate the element for the water heater, but they do make a 12 volt element for your 110 vac water heater which is set up as the "dump" for the windgens.
When the time (and money) comes, I will add a windgen to my system in order to run a 12 volt refer system. I will need to double my battery bank to capture the extra energy and efficiently run the refer system and if I find I still have an excess, I will change out the 110 vac water heater element for the 12 volt one, because I won't be running the gene for anything other than the watermaker and/or A/C, anymore. Since we ran the engine less than 15 hours in 3000 miles of inter island sailing last year, we're not getting a whole lot of hot water from that source.
Having larger than what someone on here thinks is adequate solar panels is not necessarily a bad thing for those days when one doesn't have 100% sunlight all day. My philosophy on solar is get the largest you can comfortably fit aboard (see pic for an easy installation on the bimini; notice they do not lay on the bimini, but shimmed to have air passing under them for cooling). Unless you want to constantly change the angle of your panels (as some do) you do not get full charge out of them more than several hours a day. Mine tilt slightly forward so in an easterly wind (the norm in the Caribbean) I get the most energy in the AM. They still produce current, sometimes as much as an amp around sunset, but nowhere near the 20 amps of mid-morning. Two years of using my solar and I'm sincerely happy that I opted to go with solar before a windgen. There are so many cheap, inferior and NOISY windgens out there that must make living with them nearly intolerable for those aboard and definitely a supreme irritant for those they anchor amongst.
"Any idiot can make a boat go; it takes a sailor to stop one." Spike Africa aboard the schooner Wanderer in Sausalito, Ca. 1964.