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How to Size an Energy Storage System

One of the most significant challenges that exists in the design of an renewable energy photovoltaic (PV) and Energy Storage System (ESS) is knowing how much energy storage is needed to offset your daily energy utilization.  In order to help us help you, we have put together a simple questionnaire to help you get started with appropriately sizing the ESS / PV system.

When deciding on the right ESS / PV system you will need to think about

  • Your renewable energy goals
  • What is the typical amount of electricity you consume during a 24-hour period.
  • What is your peak demand and maximum daily energy use.
  • How much renewable energy generation you will need to generate and store enough power for your home or business.

POWERSYNC and our affiliate installers can help you determine what you will need by starting right here.  Click Here if you would like to become a POWERSYNC authorized energy storage system installer.

Step 1:  Establish your PV/ESS goals

  • Do you want to reduce some or all of your electricity costs? What percentage of electricity do you want to offset?
  • Do you want to have power backup in the event of a power outage? How many days or hours of backup do you want?
  • Do you want to power your entire home or business by going off-grid or remain connected to the grid?

Step 2:  Know your energy utilization

Knowing what size ESS/PV system you will need will be directly associated with how you use energy.  Once we know your maximum daily energy utilization and peak power, we can determine how much usable energy your battery system needs to provide in order to meet your goals.

To determine this, analyze the past 12-24 months of your home or business energy utilization from by reviewing your electrical bills.  If you do not have this information or if your project is for a current off-grid facility or an RV / Marine application use our load calculator (link) to help determine your anticipated energy use.

In order to have enough energy to cover those days in which you use the most energy look for those days in the months when you have the highest use.

What to look for on your electric bill:

  • Max Daily Electricity Usage (kWh). If your electric company only provides you with monthly totals, they you will need to use an average based upon the total monthly kWh energy use by dividing by 30 (days)
  • Max Peak Demand (kW) during a 24-hour period.

Step 3:  Let us help by getting started

Our project engineers will assess the information you have provided and will present you with a comprehensive proposal which will include both lead acid and Lithium Iron Phosphate (LiFePO4) energy storage system options, solar panels, inverters, solar charge controllers, and balance of systems.

With our proposal, you will be able to evaluate the type of system that will be best for your application, the total cost of ownership, and long- term benefit of your solar PV / ESS system.

Energy Storage System / PV Sizing Questionnaire