These misunderstood little silos are all-too often misused. New POS engineers will assume they must put one between their miner and silo or their reactor and silo. The intended use is that they be placed in those positions so that when the silo is offline, product is temporarily stored in the coupling array so that it isn't lost. The reality is that these are nothing more than tiny silos and you can simply omit them from the setup and link miners and/or reactors straight to the silos.

If your POS cycles while the silo is offline, however, one hour's worth of product is lost. There is a trick to that too. Simply remove some of your fuel so you have less than 24 hours worth, and wait for your POS to mail you saying it has low fuel. The time on the mail will be the time your POS cycles. If you remember that time and simply make sure you don't have the silo offline for emptying during that time, you won't miss any product. A better use for coupling arrays is to link two together. They can hold approximately 15 hours of product each for a total of 30 hours. If you empty your silos daily, this won't be a problem and the CPU saved by using a double-coupler instead of a silo can make some very efficient and tight setups work. At 155 CPU per coupler and 500 per silo, you save 190 CPU by using a double-coupler instead of a silo.

ENERGY SAVING
Another fuel saver is to simply keep modules offline when not in use. Offline modules don't use any CPU or powergrid. While not advised for 0.0 POS, you may be able to get away with setting up guns on your POS but keeping them offline. If you are online when an attack occurs, you can quickly switch them back on. This comes with a great deal of risk and I personally do not advise it if your POS is not in Empire space.

Meanwhile, modules such as the corporate hangar array and ship maintenance array can be run for free by switching them online only when needed. They will only contribute to fuel usage if they are online when the POS makes its hourly cycle.

Another way to minimise time is to have an alternate character in your corporation and stationed at the POS with the required roles to switch modules on and offline and with access to the hangar. They can empty the silos daily in a matter of minutes and with zero travel time. If you place the silos next to the hangar array, they need nothing more than a shuttle to do so, too. And if there is fuel in the hangar and it is close enough to the tower, you can even top the fuel up that way.