Calculate Your Solar System Size

Frequently homeowners desire to calculate their solar system needs based on their actual equipment to be powered.  This is often motivated by purchase of new a new home or the desire to abandon utility power and go off-grid.

SolarPowerCalc enables users to input their specific equipment and use model that reflects their hourly and daily use.

Solar System Size calculator from
Solar System Size calculation  from

The first step in the process is to select the items to be powered. Secondly, we need to enter the actual power each item uses. The duty cycle input represents the percentage of 24 hours each item will be used. Finally we can specify the number of hours the item will be used during expensive PEAK time hours. (Off-grid users can enter zero for ON  PEAK, and 24 hours for OFF Peak.)

Analysis input of electrical devices to be powered.

The user can then enter the number of days per month each item will be used.  For example, air conditioners will only be used during the summer months.

The calculator will present the  total monthly kWhr needed to power all the specified loads.  Additionally, if the utility costs have been inputted, it will show the estimated electric bill if using utility power.

Energy use calculator table shows total monthly energy use based on user-defined equipment

The user can now compare the monthly cost of a utility powered home versus the size of a solar system needed to produce an equivalent amount of energy.