How to assess seasonal energy needs for a remote cabin?

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Calculating Daily Energy Demand To accurately assess seasonal energy needs, you’ll need to calculate the total daily energy demand of your remote cabin. Start by identifying the number of occupants, appliances, and the duration of use. For example, let’s assume a 2-person cabin with a refrigerator, LED lighting, and a laptop. Based on average usage, a watt-hour calculator can estimate the daily energy demand as follows:
Refrigerator: 100-200 Wh/day LED lighting: 10-20 Wh/day Laptop: 10-20 Wh/day Miscellaneous appliances (e.g., coffee maker, radio): 20-50 Wh/day Total daily energy demand: 140-290 Wh/day
Sizing Solar Panels To determine the required solar panel size, consider the daily energy demand and the available sunlight hours in your area. A general rule of thumb is to size the solar panel array to provide 20-30% more energy than the daily demand to account for inefficiencies and variability. For our example, let’s assume 24% efficiency and 6 hours of direct sunlight per day.
Daily energy demand: 220 Wh/day (30% above 140 Wh/day) Required solar panel power: 220 Wh/day / 24% efficiency = 915 W
Seasonal Energy Needs and Storage When assessing seasonal energy needs, consider the variations in sunlight hours, energy demand, and storage capacity. For example, winter months may have shorter sunlight hours, increasing the reliance on stored energy. A typical deep cycle battery can store 100-200 Ah of energy, and a 12V system requires a minimum of 200 Ah to run a refrigerator for 8 hours. Consider the following:
Winter months: 50-70% of daily energy demand stored in batteries Spring and fall months: 30-50% of daily energy demand stored in batteries Summer months: 10-30% of daily energy demand stored in batteries