As uninterruptible power supplies become more environmentally friendly, just what does it take for products to be classified as Eco UPS Systems. As the technology within UPS systems has been developed overall footprints have reduced and operating efficiencies have risen. A traditional uninterruptible power supply had an on-line operating efficiency of around 90% but today a true Eco UPS System will have an efficiency of around 95-96% in its on-line double conversion mode. Furthermore this operating efficiency can be extended to 99% when the UPS is run in an Eco Mode which mimics line interactive operation. In Eco Mode the inverter is active but does not directly power the load. The mains presence and power quality is monitored and the inverter is used to power the load only when the mains fails or the quality becomes too unstable. Most Eco UPS systems with this type of facility can also adopt a Smart mode where the UPS itself chooses when to operate in On-line or the energy saving Line Interactive one.
The biggest consumable within an uninterruptible power supply is the battery set and here again an Eco UPS system must demonstrate some form of technical advancement. The more modern uninterruptible power supplies now feature battery management electronics and algorithms that are designed to reduce battery usage and extend its operational life. The former is done by widening the input voltage window of the UPS to reduce battery usage and the latter through more sophisticated battery charging processes that can even include simply allowing the battery to slightly discharge itself over a time period before the charger kicks back in.
Most uninterruptible power systems now classified as Eco UPS systems also carry some form of certification for energy usage. The Energy Star rating is being applied to some UPS systems within Europe. Additional awards come in the form of meeting criteria for inclusion on the UK government’s Energy Technology List run by the Carbon Trust. UPS systems that meet or surpass the threshold energy levels for 25/50/75 and 100% load are included on the list allowing their purchasers to benefit from enhanced capital allowances.
A further consideration for an Eco UPS System is its scalability. Installing a modular UPS system like the Eaton 93PM UPS allows a UPS to be right-sized from day one but with the capability to scale as the load grows. This type of Eco UPS System is more environmentally friendly because it prevents over sizing the UPS a the initial installation and allows the UPS to be expanded to meet demand.
Final consideration should also be given to the end-of-life recycling of an uninterruptible power supply for it to be considered an Eco product. UPS will typically operate from 10 to fifteen years if they are maintained and have their consumable parts replaced at the right intervals. For batteries with a design life of 5 years this is around year 4 and for batteries with a design life of ten years around year 7. Other consumable parts include fans and capacitors that are typically replaced around year ten. Once a UPS system has reached its end-of-life it must be recycled correctly with its constituent parts broken down into and recycled through correctly managed waste streams.
Most uninterruptible power supplies can now be classified as Eco UPS systems thanks to their overall operating efficiency and energy savings and treatment of consumables like batteries.