This post will go in-depth into the technical explanation of why 24VDC (Volt DC) is better than 12VDC. There are many advantages to choosing a higher DC supply voltage. In essence the higher the voltage for a permanent holiday lighting system, the better the vibrancy of the colour and brightness.

       – At any given load, half the direct current voltage and the loss are reduced by 25%, which will reduce the risk of a fire.

       – Better voltage regulation and less power loss. 0.5 V to 12 V line drop = 4.6% power drop, while 0.25 V to 24 V line drop = 1.04% drop. This means the 24v is sustained for a longer period, and fewer wires or amplification will be required down the line.

       – Improved efficiency and regulation of the transformer. i.e. less loss on converting from 110 VAC. The transformer doesn’t have to work as hard to keep its DC power stable.

       – The United States Department of Defense and US Military likes to use this as its the largest usable operating voltage window available from batteries.

With a high-quality transformer, they would be able to handle high peak demand of up to 3 kW. As a general rule, the maximum current consumption of the inverter should not exceed 120-140 amps. If your application exceeds 3 kW, then it’s best to choose a 48-volt system. At 150 amps is the range of inexpensive wiring, switching, circuit breakers and fuses.

In short, your power consumption should determine the voltage of your power consumption. It should not have a direct current of more than 100 amperes. In most low voltage applications, it doesn’t even come close to this number.

Power – Current – Voltage

At 12 volts and 1000 watts its 83 amps

Double the wattage with 2000 watts. It’s only 83 amps at 24 volts.

48 volts at 4000 watts = 83 amps

20,000 watts = 83 amps at 230 volts

The higher the current (measured in amps or amps), the larger the component must be. Higher currents require larger diameter cables and fuses, both of which are expensive. Doubling the voltage gives you twice the power (watts) from the same current.

Dealing with currents above 100A is expensive (and therefore inefficient) and potentially dangerous. One aspect: a typical household extension cable has a maximum output of 10A. to run. 100A would probably melt it, and a fire could happen! But with low voltage applications like permanent holiday lights, you won’t have to worry about this because they don’t even go over 350 watts in the majority of applications.

Industry-standard

Twelve volts was once the standard for ultra-low voltage systems. Most systems nowadays are 24V or 48V. Popular uses are e-bikes and e-scooters that use 48v.

This means that house cabling does not have to be isolated/shielded from other homes connected to the network, and the cost of cabling is greatly reduced.

24 Volts: Advantages

Using a 24-volt power supply instead of a 12-volt power supply cuts the cost of the cable to about half the original cost. This is because an increase in voltage in a system leads to a decrease in the current flowing through the system and thus a reduction in the number of cables required. 

Reducing the size of the cable reduces costs because the thicker the cable, the more expensive it is. Another advantage of 24-volt power supplies is that they are more compatible with AC equipment. However, if you need a 12-volt power supply, you can easily reduce the voltage from 24 volts to 12 volts with a charge regulator.

12 Volts: Disadvantages

While 12 volt systems are the most popular in the market, they have the disadvantage that the transformers simply cannot raise that voltage to a higher voltage because most of them only work in reverse. The other downside would be if you wanted to upgrade to a 24-volt system, you would have to change the entire system. In terms of permanent holiday lights, the lower voltage affects the vibrancy of the colours and brightness.