DC Pump is Better than AC Pump in Solar Pumping System

DC pumps usually use DC motors, which can directly convert electrical energy into mechanical energy to drive the water pump. The AC pump system needs to use a photovoltaic water pump inverter to convert the DC power output by the photovoltaic array into AC power, and then drive the water pump to work. Next, inverter.com will tell you the advantages and disadvantages of AC pumps and DC pumps and why DC pumps are better.

Then which one is better, the AC pump or the DC pump?

We usually use DC pumps in low-power capacity systems up to 5kW, but there are some factors to mind when selecting one of them, as each has advantages and disadvantages as well.

• Price
  While the DC pump is more efficient than the AC pump and requires fewer solar panels to operate, it is difficult to maintain in remote areas as it needs specialized service centers, and you will not be able to run for an emergency at night time, also its price is higher than AC pump.
  For the price, an AC solar pump will be less expensive of course.
• Service life
  For Life span, a DC solar pump has a longer lifetime as it uses motor coils manufactured from pure copper, while an AC solar pump uses motor coils manufactured from aluminum/copper to achieve a competitive price.
• Noise
  For noise, the DC pump is less noisy, it is quiet because it uses an internal BLDC motor with high manufacturing technology while the AC pump uses old motor technology, moreover, the noisy sound of the AC pump will increase with time usage increases.

Consequently, now it is clear that using a DC pump is much better than AC pump.

DC Solar pumping system component

Mainly the DC solar pumping system consists of solar panels, a controller, and the DC pump. The most important part is the DC controller which has 4 important rules:

1. Regulate DC input voltage to hit max power point tracking (MPPT), so running the pump at the highest efficiency.
2. Automatically start and stop the pump.
3. Soft starting the pump.
4. Provide various kinds of protections like overcurrent, short circuit, over-voltage, under voltage, and over temperature.

The DC controller also has a display to show real-time measurements for pump power, voltage, consumed current, and speed.

How to choose the DC Solar Pump?

This can be easily done by indicating the required max water flow for your application in cubic meters per hour, and the max pump head in meters.
The DC solar water pump head can be obtained by knowing the distance between the pump and the well & the distance between the well and the water tank as shown in this picture:



h1 is the head above water (water to tank), h2 is the head under water (pump to water), and d is the horizontal distance between tank and pump.
So, the actual pump head:

H=h1+h2+d/10.

For example:

h1=50m, h2=30m, d=20m.
Then H=50+30+(20/10)=82m.
The actual pump head is 82m.

According to the estimated flow and head, refer to the performance curves and select the solar water pump with the appropriate flow and head. Then confirm which working voltage 12V/24V/36V/48V/72V/110V is suitable for the solar pumping system. Or send all your requirements to our customer service, and then we will help you to choose the right pump.