PacB Group // The Types of Backup Power, and Why They Are Important

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The Types of Backup Power, and Why They Are Important

The most common devices used to provide backup power fall into three categories. Of the three, two are also able to function as primary sources of electricity when needed. The two options in question are generators and solar panels. Although generators all employ the same principle to produce an electric current, they vary widely both in their output capacity, and in the type of fuel required by the engines that drive them.

They are a common feature of many industries in which their role may vary from that of providing the only source of electricity in the more remote areas of the country, to that of augmenting the mains supply at times of peak loading, or simply acting as a standby unit to be brought online in the event of an outage or a malfunction by another generator.

When backup power is provided by solar panels, it may be used directly or stored in batteries for use at night or during a mains failure. A further possibility, for domestic users in some parts of South Africa, might be the option to channel any excess electricity obtained from solar sources back into the national grid in exchange for payments, discounts, or a reduction in the normal tariff. While perhaps more evident among domestic users, solar energy is rapidly gaining ground in commercial and industrial circles, as evidenced by the many office parks and factory premises that now display an array of photovoltaic panels.

The remaining category of backup power is that provided by a UPS or uninterruptible power supply. These units also vary quite widely in terms of their output capacity, modus operandi, and the applications for which they are best suited. Nevertheless, they all share a common purpose, which is to ensure that there is no delay between the failure of the mains supply, and the initiation of the secondary source that might threaten crucial activities.

Whereas a delay in switching sources for several seconds, or even several minutes, may not lead to a disaster in many cases, and manual switching may be quite adequate, those few seconds without electricity could prove extremely serious in some situations. The most common scenario in which backup power is provided by a UPS is found in the IT sector, and in any business where the collection, processing, storage, and retrieval of data is crucial to its performance.

While the banks, insurers, and finance companies are those most reliant on UPS technology, in its own way, it can be just as important to anyone who routinely uses a desktop computer. While losing all record of one’s online gaming success might be cause for a temper tantrum, having one’s family photos or the draft of a first novel corrupted beyond retrieval as the consequence of a mains failure could prove to be heartbreaking at best.

When a UPS is employed to provide backup power, this may be obtained from a variety of sources, depending on the nature of the installation. In its simplest form, a standby unit is used to protect PCs. Operational mains electricity charges a battery, and is filtered in parallel to stabilise A/C input to protected devices. When a mains failure is detected, a transfer switch directs battery power via an inverter to the devices. In a version known as a line interactive UPS, the inverter remains connected and provides superior smoothing of spikes in the mains supply.

In more demanding environments, and where delays in switching could cause problems, a battery alone will not be sufficient to satisfy the much greater demand for backup power. In such cases, the secondary input may be provided by a more powerful source, such as a diesel generator, brought online by the transfer switch when required. There are also installations in which the secondary power source is a solar array.