Sustainability at UWA

UPS low cost independent power supply

Using a UPS for an independent power supply

Low cost independent or remote power supply using a UPS

An Uninterruptible Power Supply (UPS) can be used to build an independent power supply system. The UPS would supply the most expensive component of the system the sine wave inverter- free of charge, these are usually about $1.20 per watt of rated output. So a 1500 Watt continuous rated sine wave inverter would typically cost around $2000. UPS systems are often thrown away when their batteries go flat and yet are in perfect working order otherwise.


The black bit is a usual PV power system, the red bit is where you would normally have the inverter. The UPS has a sine wave inverter in it. These are often thrown away with once the small battery bank in them fails the inverter is usually in good order and includes a battery charger.

UPS system the hardware


Solar panels 480 Watt polycrystalline 48 Volt DC nominal.

UPSregulator  UPSsystem  UPSback

Voltage regulator PL20 From panels to battery; 
Battery bank replacing internal batteries lead acid 48 Volts DC, 130 Amp.hour second hand.
UPS, 2.4 kWatt peak, 1.5 kWatt continuous rating 48 Volt DC battery bank.

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