Solar Battery Warranties Compared: Enphase, Generac, Tesla & SolarEdge

---

Solar Battery Warranties and Common Failures

In this post, we will answer the following questions:

• Why do residential, commercial, and industrial solar owners need to use solar batteries with solar panels?
• How do solar batteries work throughout their lifetime?
• What often goes wrong/common failures of solar batteries?
• What do you need to compare when researching battery warranties?

Why are solar batteries important for residential, commercial, and industrial solar owners?

Around-the-clock electricity

When you have a solar array with no battery storage in place at night or whenever solar power is not generated, power must be drawn from the grid, i.e., the utility company. This makes energy more costly, and when demand is high, you pay more than if you had stored your energy collected during the day. Instead of depending on the grid for power, solar battery storage allows you to store and use your own electricity around the clock. This is especially helpful for homes and businesses running in more remote areas or where power failures occur more frequently.

Savings on energy costs

With a battery, we gain more control of our electrical utility bills. Battery storage helps us use cheap energy that has been collected and allows us to save it for later, assuring that our rates remain low and that our monthly expenditure is not impacted by peak demand hours and external energy issues. In certain circumstances, you may leverage net metering to earn energy credits by selling excess power back to the main grid during peak demand.

Efficient Monitoring

A solar battery storage system can improve control of your system’s power, offering a higher degree of visibility and accuracy. This is especially helpful for businesses that closely watch energy expenses and solar system operations. These devices allow you to monitor the energy a home or facility generates and consumes in real time. It also provides insight into the data necessary for strategically shifting energy loads. 

Backup power

A solar battery storage system keeps us safer in times of energy distress: when power is out, during a storm, or in any event that shuts off power. Our solar battery stores the additional energy generated by our photovoltaic modules, giving us a backup charging station. This solar battery bank is required with an off-power system to provide electricity at night and in bad or extreme weather conditions. 

How do solar batteries work throughout their lifetime?

Solar batteries have become an increasingly logical addition to harnessing and collecting solar energy due to the increasing cost of electric bills throughout the nation. Extra energy not used during collection can be stored for future use. A solar photovoltaic system’s surplus energy is placed into the battery. This implies that any excess energy may be stored on-site and used when panels aren’t producing enough during the night or in extremely cloudy weather.

Installation of the battery bank and solar panels can be conducted simultaneously. If a solar panel system is already in place, a battery can be added to the current system. 

A grid approval process for adding a battery is similar to a solar panel installation. The process doesn’t have to be repeated once installed, and the battery becomes fully operational, i.e., ready to store power.

During hours of sunshine, the solar system powers the battery instantaneously. When the evening comes, and solar panels cease generating power, solar batteries begin powering homes, offices, and industrial facilities.

Once the power is exhausted from the battery bank, the home or facility will start drawing power from the main grid. The capacity of the solar battery defines the overall charging period. A 12-volt solar battery, for instance, can require around 5 to 8 hours to charge completely.

What are common issues with battery storage?

On occasion, solar batteries fail before their expected life. Failures happen, and sometimes there are warning signs. Common failures occur with solar batteries, shortening their life expectancy.

Complete discharge of the battery

Each solar battery has a limited number of cycles (cycles represent the charge and discharge of the solar battery). This cycle is affected by the battery’s charging depth and Debt of Discharge (DOD). A very high DOD is one of the leading causes of solar battery failure.

Heat and over-charging

Overcharging or overheating batteries can lead to battery cell deformation and deterioration, causing plates to come into contact in this condition. This often happens when solar panels produce more current than their rated voltage without the proper control equipment. Usually there is a component to stop the battery from overcharging. Over time, overheating and overcharging can lead to:

• shorter running times between charges
• shorter battery life
• longer charging times
• ultimate battery failure

Vibrations

A solar battery must be placed in a stable position. Vibrations can cause connections to slip, the casing to break, and internal parts to be damaged.

Unsuitable storage

Storing moist cells for longer than the manufacturer recommends encourages sulfation, which reduces solar batteries’ capacity and lifespan.

Mis-application

Batteries are frequently made for a particular purpose. If the battery is not made for a specific use, it may function or last as long as it should.

Solar Battery Warranties and Features to Compare

Batteries account for such a large portion of PV system expenses. Therefore, it is critical to examine the manufacturer’s warranty and standards to verify the eligibility of a warranty claim.  

The warranty features to consider when choosing a battery for your home include:

• Manufacturer’s Warranty – standard time the manufacturer covers the battery
• Number of Cycles – how many times a battery will charge and drain (1 cycle)
• End of Warranty Capacity – a guarantee that the battery will hold a certain amount of capacity throughout the warranty
• Warranty with Solar Insure – A solar warranty covering battery storage.
• Output Power – the higher the wattage rating, the greater the amount of power your solar installation will produce
• Bankability – how does the company protect customers in case business doors close

Solar Battery Storage Warranty Comparison Chart

Below is a comparison of features for major solar battery brands on the market today: Enphase Encharge, SolarEdge 9.7KWH, Tesla Powerwall 2, and Generac PWRcell.

Solar Insure Battery Warranty

Solar Insure delivers select brand battery warranty coverage for 20 years below 50% capacity. Learn more about Solar Insure for partners and homeowners.

Resources

Chtita, S., Derouich, A., El Ghzizal, A. and Motahhir, S., 2021. An improved control strategy for charging solar batteries in off-grid photovoltaic systems. Solar Energy, 220, pp.927-941. 

https://www.energysage.com/solar-batteries/tesla/6/powerwall-2/

https://www.solaredge.com/us/warranty-check

https://www4.enphase.com/en-us/stories/encharge-battery-better-choice-for-customers-and-business