Electrical Review: The Ultimate Power Struggle – Should I Repair Or Replace A UPS?

It’s not strictly a superhero battle between good and evil. But when it comes to an ageing UPS system, it’s still a big call whether to repair or replace.

Every data centre operator or IT manager will face up to the question eventually. Do you squeeze out as much life as you can from your existing uninterruptible power supply? Or bite the bullet and invest in a new and more efficient system?

We investigate both sides of the argument for Electrical Review in a special front cover feature accompanied with an eye-catching cartoon-style visual.

Cartoon style image with a male electrical engineer and a Riello UPS Multi Power along with the caption repair vs replace
WHICH SIDE ARE YOU ON? Whether to maintain or replace an ageing uninterruptible power supply is a key decision for any IT manager or data centre operator to make

First things first. There are instances where there isn’t even a choice. For example, if a UPS is phased out of production and no longer supported by the manufacturer, it can be so hard to get spare parts that maintenance becomes prohibitively expensive, even impossible.

Similarly, if the firmware doesn’t comply with latest security protocols, the UPS will be prone to communication problems and susceptible to cyber-attacks.

In these situations the options are limited – you’ll need to replace your UPS with a new system.

What Factors Influence Whether To Maintain Or Upgrade?

To start with, IT managers should consider a couple of key criteria:

  • Whether they are planning to outsource: if a server room is full to capacity or packed with aging equipment, might outsourcing to a colocation be an option? If yes, then the vendor will acquire responsibility for UPS system maintenance.
  • Current and future load requirements: Are you near full load and expecting your power requirements to keep growing? If so, do you have scope to expand your existing UPS? Or might you be limited by the number of modules or units that can be paralleled together? On the flip side, what if you’re consistently running light loads? If that’s unlikely to change, then could you benefit from downsizing? That could mean enhanced efficiency, reduced number of batteries, and a system that’s easier to maintain.

Stick Or Twist: Repair Versus Replace

So what do both options involve? Continuing with a legacy UPS might involve an overhaul of key components such as fans and capacitors. This costs less than buying brand new, and does extend a unit’s service life. But in some respects, this is just delaying the inevitable. At some point – whether sooner or later – the UPS will need replacing.

Replacing a legacy unit with new requires upfront cash investment. In addition, it also increases the short-term risk of something going wrong while the new system beds in.

But any potential downsides are significantly outnumbered by the longer-term advantages.

Older uninterruptible power supplies are likely to be transformer-based and inefficient. They’ll waste lots of energy and need plenty of electricity-guzzling air conditioning.

It’s more than likely such monoblock units will take up significant space and have been oversized at initial installation too.

On the other hand, modern UPS power systems are based on efficient transformerless technologies. This means high efficiencies from 94-99% are achievable even at low loads.

Modular UPS, in particular, are far easier to right-size at the start. Power rating and redundancy can closely match actual load requirements. That means minimal wasted energy.

Operators also have firm control of the total cost of ownership (TCO) as they can ‘pay as they grow’ by adding more modules when needed.

Here’s a comparison between a legacy UPS and a new modular Multi Power (MPW) system. Bear in mind this doesn’t factor in air conditioning costs, which would be much higher in the legacy configuration.

Legacy UPS vs Modular UPS
Legacy 120kVA N+1 Modular MPW 126kVA N+1
Load (kW) 96 96
UPS Efficiency (%) 91 96.20
Total UPS Input Power (kW) 105.50 99.79
kWh Price £0.09 £0.09
Total Electricity Cost Per Year £83,171 £78,676
Saving Per Year £4,495
Saving Over 10 Years £44,950

Other Benefits Of Buying A New UPS

  • Modern UPSs have a higher power density than their previous iterations. This means they’re lighter and take up less space, making them easier to install.
  • Floorspace is freed up for either extra server racks (higher revenues) or batteries to participate in energy storage (lower electricity costs).
  • User-friendly display panels and cloud-based remote monitoring capabilities enhance operator control and reduce day-to-day running costs.
  • Efficient new UPS are likely to feature on the Energy Technology List (ETL). This means IT managers could be eligible to claim back the costs against their taxable profits.