Getting The Most From Solar Storage

With the recent return to loadshedding, accompanied by regular and often prolonged power cuts across many municipalities, residents and businesses are often left scratching their heads about why their power backup is not working.

Lance Dickerson, MD at battery storage solution provider REVOV is confident he can guess the reason. “During the height of the loadshedding pandemic – because that is what it was, it was throttling our economy – there was a mad rush to invest in solar and uninterrupted power backup solutions,” he says. “Every installer and their uncle, even those who had just joined the industry out of opportunism, were making promises about quality and expertise to get the signature on the dotted line. Payments were made, installations were completed, and households and businesses believed they were protected against unpredictable and unreliable power supply.”

Wet and overcast conditions are often when people first realise there’s something wrong with their solar and battery back-up system. “People rely on their installations to shield them against being left without power and expect the system to last, which is not unreasonable considering that many of these systems are only a year or two old.”

In a properly functioning system, solar panels should be generating power when the sun is shining, and batteries should be storing that power that’s not being used. But these are complex systems that involve panels, batteries, inverters and electrical engineering, Lance says. “They should never be attempted by uncertified installers. When things don’t work as they should, that’s when people struggle to find support or are left in the dark.”

“The same goes for home uninterrupted power supply (UPS) systems – whether automatic systems or plug-and-play variations,” he says. “Safety is the first consideration – electricity is dangerous when things are done incorrectly – but poorly configured setups also end up shortening battery life. Poor advice and no service simply leaves people with expensive decor, rather than a trustworthy backup system.”

REVOV founder and MD, Lance Dickerson.

Tips to ensure your backup batteries work when you need them

What can people do to prolong the life of their power backup systems? “There are a few non-negotiables if you want to ensure your system does what it is supposed to, when you need it to,” Lance says. “The following tips apply for any reputable company that installs world-class systems from reputable brands.”

1. Always work with reputable suppliers and installers

This may seem obvious, but it cannot be overstated. When it comes to brands of batteries, seek out those that have stood the test of time and that come with full local support in case something does go wrong. Any brand that has been around for less than three years came to town during the loadshedding peak and is likely not in the business for the long haul. Look for geographical footprint. Ideally, you want to have expertise that can provide support as and when you need it. Some battery brands require overseas support and those waiting times certainly won’t benefit a business, for example, which needs backup for business-critical functions.

2. It’s all in the chemistry

By now, most people should have a good, clear understanding that lithium iron phosphate (LifePO₄) batteries are superior in every way to the cheaper lead acid and other lithium-ion chemistry batteries. What fewer people know, and which is very important, is that 2nd LiFe lithium iron phosphate batteries come with an added advantage.

Because the cells are repurposed from electric vehicle batteries, they have had to pass far more stringent performance and safety tests than batteries made exclusively for storage. In harsh African conditions, this is a compelling advantage.

3. Ensure battery charging is optimal

Avoid fast charging as much as possible to prolong a battery’s life. Secondly, avoid allowing a battery to drain completely. Even though it’s lead acid, think about the time your car’s battery drained completely – it was never the same again. The optimal state of charge for batteries is between 20% and 80%, but a full charge to 100% regularly is crucial to maintain maximum capacity and correct state of charge parameters. This is how you prolong battery life and enjoy the best performance.

4. Batteries perform best at room temperature

Extreme hot or cold can damage battery cells and reduce their lifespan, which means the ideal battery location is an enclosed, cool space. However, this is not always possible, which is why the hardier, proven resilience of cells in 2nd LiFe batteries, which have endured extremely hot temperatures and rapid charge and discharge rates in their life in an EV, are often preferred.

5. Long-term storage requires some preparation

If you are going to store batteries for a long time, there’s a procedure you need to follow to ensure the best health for your batteries. Charge the battery to 50% before you store it. After six months, run your battery through one full cycle, then re-charge to 50% and store it again.

6. Avoid battery overuse

Ensure that you have the correct numbers and configurations of batteries for your demand. Do not overload your system and whenever possible, prioritise essential loads. Running a system at maximum load or 1C every day is a sure way to reduce its life. The best way to ensure this is done correctly is to work with approved installers who have the support of local battery supply teams. Always listen to, and never ignore, system alarms and warnings.

7. A little exercise is needed

This may sound bizarre, but your own body operates better when it is exercised. It is the same for batteries. Discharge and charge your system by 25% every seven days – this prevents long-term degradation. A properly designed installation will take care of this. For UPS systems, ensure they remain plugged into the power source to ensure the batteries are optimally charged to protect against unexpected power cuts. Avoid micro cycling, a situation where the battery is discharged by less than 5% and recharged multiple times a day.

With these seven principles in place, solar energy and battery backup systems should provide many years of reliable service. The important thing is not to take their performance for granted. Take care of the things you would like to take care of you.