Solar power calculator for solar power battery systems

roof top solar and batteries for your energy needs Is solar power with batteries cost effective for you?
How many solar panels and batteries are needed to suit your situation?
What is the cost of a generator over the long term compared with solar?

Remote solar power system configuration:

Solar panels + regulator + batteries + inverter + installation - government rebates - renewable energy credits
See What does solar power cost for more solar configuration details.

Solar Power System Pre-Requisites

Work out the likely electrical loads required from your solar and battery system
See Solar Power Load calculator below.
Try to be electrically efficient as possible before embarking on a solar project.
See Energy Efficiency eBook which covers 60 technologies and 54 free best efficiency practices.

Remote Solar power battery system Calculator

Total number of solar panels quantity
Single Solar Panel Height in millimetres (mm) mm
Single Solar Panel Width in millimetres (mm) mm
Single Solar Panel Power Output in (watts) watts
For more solar panel specifications see Solar Panel Calculator
Batteries Size
Your local average daily Solar Radiation World Map Solar Radiation (kWh/m2/day)World Map Solar Radiation small kWh/m2/day
Life span in years years

Press this button after adjusting values in the top table. Results are in the lower table.

Solar Power Battery System Results

Total power output of solar panels in (watts) watts
Average Solar Power Daily Output Wh watt Hours Wh
Average Solar Power Daily Output kWh kilowatt Hours kWh
Time to Charge Batteries. Assume 80% efficiency days
Lifetime Solar Power Generated kiloWatt hours kWh
Diesel Generator fuel saved over solar power lifespan. 0.35 litres per kWh litres

Solar Power Usage Suggestions

  • Try to arrange electricity loads for daytime hours. This avoid battery charging losses.
  • Keep the solar panels clean for better efficiency.
  • Arrange the solar panels so there is some natural cooling. Solar panels are more efficient when cooler.
  • Select DC appliances to minimize the inverter size required. Avoids the losses of an inverter.
  • AC Transfer switches can allow a generator to start automatically if the battery voltage is too low.
  • Allow for some seasonal solar radiation variation

Load Calculation for Solar Power Battery System

Enter the appliance name, the typical power in watts it uses and the hours per day average use.
Use the combined total to size your solar and battery system.
For some appliances consider the duty cycle when actually using power. e.g. fridges. See Appliance Energy Calculator for appliance power load values.

Appliance Name (optional)Power Use WattsHours per day use
Grand Total Watt Hours

Design your solar battery system to meet your calculated electrical loads. Solar Battery Calculator