physical size of solar panels

CA Traveler wrote:
I first installed a battery monitor to better understand my usage. There are many factors that determine solar output and many factors determine power usage. 2/3 of the panel watts for 4-5 hours/day is a reasonable ball park estimate.

Agree!

Once we retired everything changed: boondock 7-10 days instead of a three day weekends, travel south in the winter, so less daytime sun, use the furnace every night, readers and laptops to charge, and on and on.

After having a 90 day old set of AGM batteries fail we installed a Victron BMV 712 to see what was happening with our system. Best money spent!

Two years later the 712's history told us our WFCO was occasionally charging at 21 volts, and destroyed a second set of batteries. Found out our furnace can use 20-30 amps at night, just having the battery switch engaged our use can be 12 ah a day, each phone uses .9 ah and were plugged in all night, etc. It helps us control our energy use and shows us items were using more ah's than we realized.

We didn't need more/bigger batteries, although last winter we spent $1,000 on 220 usable ah's and now realize a decent set of Trojan flooded at $3-400 would have easily met our needs. We needed more solar on the roof, so 300 watts was added. We now have no problem keeping our batteries full and have added a 1500 watt inverter to make toast and charge our phones in 15 minutes.

As far as I'm concerned if you're serious, the first item I would add is a battery monitor with history (NOT the Alibaba battery monitor that lacks history). The 712 showed we didn't need more batteries than we already had, but needed more watts on the roof.

Enjoy,

Perry