I have a working solar system at my shack and was a reseller of solar equipment for around 15 years. IMO solar installations are best treated like a tank of water, you have a certain amount to use, use and monitor it carefully and your system, however modest, will deliver what you need.
At my shack (holiday home for north islanders) I run lights, a small colour TV, water pump and microwave oven. My fridge and stove are run from Gas. I have two 85 watt panels and around 500 Ah of battery storage. For intermittent use large battery banks are a good idea. My inverter is a 1200W sine wave from Selectronics (an Australian company) and will run a washing machine, 240V Onga pressure pump, Microwave oven and Vacuum cleaner.
It has remote control and will give statistics of power (ampere hours) in, out as well as control functions to allow generator start and anything else you may wish to program. Needless to say you won't buy something with those facilities from Dick Smith or similar for a few hundred dollars.
The two biggest hurdles for solar are refridgerators and freezers. Despite low power requirement refridgerators and freezers have a high duty cycle, i.e. they run a larg percentage of the time so they use relatively large amounts of power. Some have large start up currents and run poorly from inverters.
Your location and hours of sunshine will also effect the effectiveness of your solution. If you can also utilise wind power and micro hydro, these are excellent compliments to solar (and cheaper to implement). Regarding the power output of a solar panel, as a rough guide in Tasmania, mid summer and 85W panel will deliver around 35 amp hours into your battery on an average summers day, you can halve that figure for winter here as the daylight hours are less, so in my case I have around 70ah per day to use, which equates to 800 watt hours (.8Kwh) per day, more than enough for my humble needs. I run 240 volt compact flouro's for lighting and pump 100 gallons of water per day. There is enough power left over to run the lighting and water pumping needs of an adjacent shack.
Tracking can increase efficiency, but as tracking devices are relatively expensive it may be better to put any budget for tracking in to extra panels.
With batteries you get what you pay for, quality batteries don't come cheap. It's worth remembering that the shallower the discharge cycle of the battery is the more cycles you will get from the battery before it needs replacement.
In the final analysis there is no "one size fits all", you need to determine your power consumption, which, if any appliances you can run from alternate sources, and your budget and allow consideration for those days when the sun doesn't shine.
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