Estimating the Electrical Loads
The power and energy consumption of the loads is of significant importance in off-grid systems. The main questions to be answered here are:
Which electrical loads are to be supplied by the off-grid system?
How high will the energy consumption be per year or per day?
What will be the maximum power in a day?
For orientation purposes, the following table gives an overview of popular loads, their power and their typical operating times per day.
Electrical loads | Nominal power | Typical operating time per day | Energy consumption per day |
|---|---|---|---|
Air conditioner | 3000 W | 2 h | 6 kWh |
Dryer | 1000 W | 4 h | 4 kWh |
Washing machine | 2000 W | 1 h | 2 kWh |
Cooker (hob and oven) | 2300 W | 0.75 h | 1.7 kWh |
Dishwasher | 1300 W | 1 h | 1.3 kWh |
Water pump | 200 W | 3 h | 0.6 kWh |
Computer | 250 W | 2 h | 0.5 kWh |
Freezer 200 L | 100 W | 5 h | 0.5 kWh |
Kettle | 1800 W | 0.25 h | 0.45 kWh |
Refrigerator | 90 W | 5 h | 0.45 kWh |
Vacuum cleaner | 1800 W | 0.25 h | 0.43 kWh |
Television | 100 W | 4 h | 0.4 kWh |
Microwave oven | 1200 W | 0.25 h | 0.3 kWh |
Toaster | 1200 W | 0.25 h | 0.3 kWh |
Hairdryer | 1000 W | 0.25 h | 0.25 kWh |
Iron | 1000 W | 0.25 h | 0.24 kWh |
Printer | 100 W | 2 h | 0.2 kWh |
Amplifier | 100 W | 2 h | 0.2 kWh |
Heating circulation pump | 70 W | 2 h | 0.14 kWh |
Energy saving lamp | 15 W | 4 h | 0.06 kWh |
Satellite receiver | 18 W | 3 h | 0.054 kWh |
Mixer | 200 W | 0.25 h | 0.05 kWh |
DVD player | 15 W | 2 h | 0.03 kWh |
Sewing machine | 80 W | 0.25 h | 0.02 kWh |
Radio | 5 W | 3 h | 0.015 kWh |
Shaver | 15 W | 0.25 h | 0.0038 kWh |