My thoughts:
The application of formulas and such seems solid. You've done a good job of considering electrical needs for cooking, lighting, communications, cleaning, and entertainment. But what about comfort? That might include such things as space and water heaters, ventilation fans, etc. Because there's an efficiency penalty for running loads through the inverter I'd suggest you move some things out of the ac list into the dc list. Phone charger is a prime candidate; DVD, TV, and gaming PC might also be chosen to have direct dc power input options. Speaking of the inverter, these have an idle current (it might be called "quiescent") that the inverter itself consumes simply by being turned on even if there's no ac load. Perhaps there should be a line item for that. With regard to the battery charging, the math seems OK but it is a little unconventional to work in terms of amp-hours instead of watt-hours. I guess that's because solar insolation is measured in watts, and the array voltage may well be different than the battery bank voltage and thus the currents will be different too on either side of the charge controller (oh, there's another de-rating factor to add to your list: efficiency of the charge controller).
Finally: many of the hours-of-usage estimates seem odd to me. But that may well be because my lifestyle and projected usage pattern are different to yours, so I accept them as being accurate. All except the fridge/freezer, which I question a little bit. My home fridge/freezers seem to operate at 25-50% duty cycle and 100-something watts when they're on, but maybe you've chosen then numbers you did as a way to average out the value because of the duty cycle, or maybe you're looking at a continuous-load type I'm unfamiliar with.
|