Computer

# How powerful would a UPS have to be to keep your PC on for 24 hours?

For those who don’t know, a UPS is an uninterruptible power supply. Basically we could define it in a very informal way as a power strip where we can connect our PC but with a battery, so that if the power goes out it has autonomy to keep the devices on and thus not lose data or connections.

These types of devices are owned by large companies where a blackout does not cause prejudice if they have a server set up or people working at that time. Although this usually works with generators of another type since a UPS has a limited autonomy. Today we will see how much.

## Can a UPS last 24 hours?

The easy answer is no. It would be impossible, at least with the ones that exist now. Although it all depends on what you want to keep. A computer with its monitor, router and printer working is not the same as a NAS or a simple router.

Today there are many brands and products on the UPS market, we can find some very basic and cheap ones, like this one from Green Cell with a power of 600VA (360W) which would be designed for micro power outages since it could not support the load of a PC with its monitor for several minutes (if it manages to resist it with only 360W of maximum power), although it would help us to maintain a router for a good period.

On the other hand, there would be more professional models like this one from the Schneider brand, with a power of 2200VA (1400W), which would already give us more than 1 hour of connection with our PC and monitor and several from a router.

The important thing comes to us when we look for it to last 24 hours, in this case if we have a PC + screen only, which consume on average over 250W. We should go to a UPS that would be impossible to commercialize due to cost and size. Its manufacture could exist but it would not be profitable.

The calculation of the time that the autonomy of a UPS would last is calculated based on the following formula:

Time (min) = [(Número de baterías x Voltaje x Amperios/h x Eficiencia)/ VA]*60

Being VA the power of our UPS that is calculated by dividing the consumption (in this case 250W) x the power factor that is between 0.6 and 0.7, but being pessimistic we will leave it at 0.6. In the example now it would be 250/0.6 = 416VA

That is, to get those 1440 minutes that a full day has, the number of batteries, voltage, amps and other factors would have to be extremely high and expensive.

We would have to go to about 100 12 V and 9Ah batteries to produce energy for 24 hours, counting that professional teams have about 6 batteries of this type. I would have to put together about 16 professional teams.

If we want to achieve it, we would have to go to power generators like this one, which are very expensive and would not be for domestic use either. UPSs are prepared for power outages and emergencies, not as external batteries.

So if you were thinking of buying a device that could withstand your computer in the event of a power outage for a whole day, I have to tell you that for now you will have to wait or buy an external power generator.