Written on behalf by Madeline Acri, National Energy Storage Specialist at Soligent
Last month we discussed how utilities began adopting net metering practices across the US back in the 1980’s. Now however that we are in the 2020’s, we are beginning to see net metering policies decline. Time of use billing structures are popping up more and more as a replacement option to net metering. While this may be less favorable for solar only installations, it creates a great opportunity to install batteries to add value to your system. But if we add batteries to our PV, how do we know if our PV is sized properly? When considering a battery installation, the first step is to identify how the battery will be used for the home. Will the battery backup my entire house during an emergency outage? Will the battery be discharged from sunset to sunrise in a solar self-consumption manner? Deciding how the battery will run is important to establish how deeply the battery will be discharged and how frequently the discharging will occur. Once this is set, the PV can be easily measured based on anticipated sun hours shined each day. After calculating the battery bank size and the accompanying PV array size then the total inverter power can be measured. Starting with the battery bank, then moving to PV, then the inverter is the most logical way to “follow the loads” and make sure the sizing is appropriate. This will be discussed in more detail during the upcoming Basics of Energy Storage webinar series.