Lithium iron phosphate batteries are THE SOLUTION TO securing connectivity during LOADSHEDDING

As the two founders of REVOV, we spent more than a decade in the telecoms industry where a lot of work went into designing, planning, implementing and testing various ways to keep telecom towers running in various regions of Africa. The challenges were many, but the premise was simple: how do we keep towers running when generators aren’t an option and there’s no electricity?

BY LANCE DICKERSON*

This is where our foundational understanding of the power of batteries and their application in telecoms specifically, and power backup generally, was developed. At this point, it is vital to introduce the topic of chemistry. Batteries work through chemistry and many of the painful lessons we learnt prior to launching REVOV in 2015 were down to the limitations of lead acid technology, a lesson no doubt still being learnt by many a telecom company on this continent.

Lithium batteries are without any shadow of a doubt the superior batteries. Many reading this will have used a volatile type of lithium battery called nickel manganese cobalt (NMC) more than they realise in their smartphones or laptops. These batteries are known to ignite at higher temperatures.

A newer, superior chemistry called lithium iron phosphate has emerged as the safest, most stable and longest-lasting of storage battery chemistries. Beyond this, lithium iron phosphate 2nd LiFe batteries, which are built from the repurposed but fully functional cells of EV batteries, come with the added benefit of engineering built for harsh operating conditions – think of the heat and charge-discharge ratio in the usage of an EV. LiFe, in the name 2nd LiFe, is a word constructed from the periodic table symbols of lithium (Li) and iron (Fe).

So, as a base understanding, we land on 2nd LiFe batteries as prime candidates for backup storage, either for renewable energy installations or uninterrupted power supply systems. In this case, 2nd LiFe is primed for telecom tower battery backup, and this is why:

In a properly set up and configured 2nd LiFe lithium iron phosphate battery backup system, the time to recharge is identical to the time of discharge. The 1:1 ratio means that if the battery has been used for four hours, it needs four hours to recharge until its full. If it has been used for six hours, it requires six hours to be recharged until full. Beyond this, the discharge curve is stable, and unlike lead acid doesn’t plummet after a critical point in time, which makes them fundamentally different to lead acid batteries, not just in performance, but reliability and lifespan.

This provides a compelling answer to batteries being rapidly recharged in the gaps between bouts of loadshedding in the higher stages. However, the transmission infrastructure of some areas leaves a lot to be desired, and in some instances there quite literally is not enough current. Beyond this, some areas do not return after loadshedding because of various technical faults meaning areas are in the dark for far longer than anticipated. Another factor is the breaker size used at each site, which will determine the performance of the system during recharge periods.

While these are technical discussions, an analogy for a layman’s understanding is: presuming the sites already have remote generators that are 10KVA, for example, the following could easily be done. We must understand that a generator cannot be run under capacity for extended periods of time, as much as it cannot be overworked for extended periods, lest the life of the machine is severely compromised. And so, running a 10KVA generator could split 7KVA to charge batteries while 3KVA powers the tower. As a stop-gap measure this prepares the site for the next power outage, remembering that the superior lithium iron phosphate performance enables a 1:1 discharge to charge ratio.

The point is that we are all in the throes of a devastating crisis that threatens our very economy. Working together, bringing expertise from various sectors, South Africans really can come up with compelling solutions to the crisis. In the absence of this, and certainly in the absence of any largescale understanding of battery chemistry, the status quo will no doubt continue as we wait for Eskom’s crisis to finally be addressed, and this won’t be tomorrow, next month or next year.

Sodium-sulphur batteries (NAS® Batteries), produced by NGK Insulators Ltd., and distributed by BASF, with almost 5 GWh of installed capacity worldwide, is the perfect choice for large-capacity stationary energy storage.

A key characteristic of NAS® Batteries is the long discharge duration (+6 hours), which makes the technology ideal for daily cycling to convert intermittent power from renewable energy into stable on-demand electricity.

NAS® Battery is a containerised solution, with a design life of 7.300 equivalent cycles or 20 years, backed with an operations and maintenance contract, factory warranties, and performance guarantees.

Superior safety, function and performance are made possible by decades of data monitoring from multiple operational installations across the world. NAS® Battery track record is unmatched by any other manufacturer.

Provide for your energy needs from renewable energy coupled with a NAS® Battery.

Contact us right away for a complimentary pre-feasibility modelling exercise to find out how a NAS® Battery solution can address your energy challenges!