Detailed DC system design
Location: Pampachiri, Apurimac, Peru
GPS coordinates: 14°11'37.65"S 73°32'31.73"W
Altitude: 3378m
Description: A two story adobe home in the Peruvian Andes with only DC power needs.
Photo of the home.
Location of the home.
DC load evaluation
| # | Load | Quantity | Watts | Total watts | Duty cycle | Hours per day | Days per week | Average daily DC watt-hours |
|---|---|---|---|---|---|---|---|---|
| 1 | Cree 5 W LED | 6 | 5 W | 30 W | 1 | 3 hours | 7 days | 90 Wh |
| 2 | Retekess radio | 6 W | 1 | 6 W | 1 | 5 hours | 7 days | 30 Wh |
| 3 | Samsung cell phone | 2 | 10 W | 20 W | 1 | 1 hour | 7 days | 20 Wh |
| Total average daily DC watt-hours | 140 Wh | |||||||
- Load: The make and model or type of load.
- Quantity: The number of of that particular load.
- Watts: The power rating in watts of the load.
- Total watts = Quantity × Watts
- Duty cycle = Rated or estimated duty cycle for the load. If the load has no duty cycle a value of 1 should be used. A load with a duty cycle of 20% would be inputted as .2
- Hours per day: The maximum number of hours the load(s) will be operated per day. If the load has a duty cycle 24 hours should be used.
- Days per week: The maximum number of days the load(s) will be operated per week.
- Average daily DC watt-hours = Total watts × Duty cycle × Hours per day × Days per week ÷ 7 days
- Total average daily DC watt-hours = sum of Average daily DC watt-hours for all loads
Average daily watt-hours required
| Average daily watt-hours required | = Total average daily DC watt-hours + Total average daily AC watt-hours |
|---|---|
| Average daily watt-hours required | = 140 Wh |
