A Beginner’s Guide To Solar + Battery Storage

We know that the Solar jargon can be confusing, which is why we’re starting a new blog series, “Solar School for Beginners.” This new series aims to make Solar terminologies a little easier to understand. Battery-related definitions can be found at the bottom of this page. But, if you’re looking for general industry definitions, check out our ever-expanding glossary here. 

So, What Is Solar With Battery Storage?  

A solar battery is a device that is charged with energy from Photovoltaic (PV) panels. Batteries allow you to store excess electricity generated by solar panels, and source energy at times when you’re consuming more electricity than your PV system produces, such as when it’s nighttime. They can be used in both grid-tied and off-grid applications. 

There Are Different Battery Types? 

Yes! Here are a couple examples: 

Lithium-ion*
  • Requires little-to-no maintenance
  • It has a moderate-high upfront cost, but it is generally quite cost-effective in the long run 
  • It is approximately 1/3rd the weight and size of lead-acid batteries  
  • Has an average lifespan of over 10 years 
  • Best for residential usage (it’s the most common type used)
Lead-acid 
  • Regular maintenance is required
  • It has a lower upfront cost
  • Its size depends on the system makeup, but it is usually medium-large
  • 4-8 years is its average lifespan 
  • It is most common for off-grid usage 
    • Note: It requires a suitable charge controller for off-grid  usage 

 *There are several types of lithium-ion batteries, but only two are regularly used in residential applications: Lithium Nickel Manganese Cobalt Oxide (NMC), and Lithium Iron Phosphate (LFP). 

Benefits 

Although you don’t need solar batteries for your solar system to work, there are plenty of reasons why people choose to include them. 

For instance, solar batteries are great for those who want to be completely self-sufficient with their energy, and/or for people who want backup in case of power outages. Another benefit of having batteries as part of your solar system, is that it lets you pay less for electricity during peak hours (utility-company permitting)! Peak hours occur when so many people demand energy simultaneously, that the utility company raises its prices; if you have a battery bank, during those hours, you can source your energy from there instead.  

 

Schneider-Electric-Solar-solar-and-storage-system-in-Grundfos-facility-1048x768 - Copy
red_cross_micro-grid_project_puerto_rico5-768x384
XW Pro system installed with Li-ion batteries
(batteries on top left)

 

Red Cross Case Study Upgreen & Grundfos Case Study

Considerations 

Below are some important factors to consider when choosing the right solar battery: 

  • The application  
  • Battery lifespan 
  • Battery capacity 
  • Depth of Discharge (DoD) 
  • Temperature (most batteries are at least somewhat sensitive to temperature) 
  • The battery’s power ratings 

First things first – are you looking to be off-grid or grid-tied? This is important because most of the other factors are related to this. For instance, if you are going to be grid-tied, and using the battery as a backup system, you might not need as many watt-hours as someone who is completely off-grid.  

A battery’s lifespan depends on several factors, such as deep discharges and temperature. The battery discharge refers to the usage of the battery’s stored electricity. Depth of Discharge refers to the battery percentage being discharged before it ought to be recharged; the percentage is relative to the battery’s overall capacity 

There are two types of power rating you should pay attention to – continuous power rating and peak power rating. Continuous power rating is the amount of electricity (in kW) that can be supplied continuously, for things such as freezers, which always need power. Peak power rating is the greatest amount of electricity (in kW) that can be released for short bursts; it’s mainly used for appliances such as blenders, pumps, or motor loads. 

 

There You Have It!  

Our solar and storage solutions work with a variety of different battery brands. For any questions, contact us and we’ll be happy to help you get started on your Solar journey! 

Get Started

 

Battery Terminology  

  • Battery capacity = how much energy the battery can store; it’s stated in amp-hours (Ah)  
  • Battery discharge = the usage of the battery’s stored electricity. It is when the battery’s stored value decreases  
  • Cycle life = a round of complete battery discharge followed by full recharge 
  • Continuous power rating = the amount of electricity that can be supplied continuously. It’s measured in kW  
  • Depth of Discharge (DoD) = refers to the battery % being discharged compared to its overall capacity  
  • Grid-tied = your energy is sourced from the local utility company as well as your PV system  
  • Off-grid = when you’re 100% self-reliant in your energy production; you are not connected to your local utility company 
  • Peak power rating = is the greatest amount of electricity that can be released for short bursts. It’s measured in kW  
  • PV technology = photovoltaics = generate power through energy-absorbing devices, transforming energy from sunlight into electrical energy.   
    • They’re also often referred to as solar panels, or PV panels 
  • Watt-hours = are units of electrical energy equivalent to 1 watt of output per hour. 
    • A 20W light bulb running for 6 hours uses 120Wh