Specialized Solar Systems’ Solar Agricultural installation team completed a 7.5 kW VSD system, used to power a 5.5kW 380V- AC water pump with 10.50 kWP solar array in Jeffreys Bay, Eastern Cape South Africa.

The installation was a big success and made use of 34 x 310W Solar modules (PV panels) producing a max of 10.50 kWp. The VSD (variable speed drive) was also connected with a change over switch which allows the customer to switch between Eskom and Solar when needed.  This VSD Solar Powered System was designed and supplied by Specialized Solar Systems and should make use of its maximum efficiency when pumping (5.5kWh) for 7 hours/day in summer and 5hours/day in winter.

The special operating system makes Specialized Solar Systems variable speed drive centrifugal pumps an appropriate solution in all cases where water flow rates do not ensure suitable operating pressures. A Variable Speed Drive (VSD) regulates the speed and rotational force, or torque output, of the motor.  One of the main reasons why these drives save energy is because they can change the speed of an electrical motor by controlling the power that is fed into the pump. The VSD motor also allows for a soft start and stop which reduces the violent torque , therefore extending the life of motors and functions well combined with solar generation as energy sources.

Above are some pictures of the installation in Jeffreys Bay and below is some video taken at the installation.

Background on Specialized Solar Systems VSD Water Pump Solar Powered Systems

For high amounts of water, a large AC pump is usually required. These pumps require well regulated 3 phase AC voltage and current. By using an AC variable speed controller called Variable Speed Drive 9VSD) or  a Variable Frequency Drive (VFD ) or an Adjustable Speed Drive(ASD) the pump motor will have the proper voltage and current. The trick is to supply DC from the PV array directly into the DC bus inside the VFD. The normal AC input is not used. As the sun rises and PV voltage and current increase, some VFD products will accept the input and when the power is high enough, it will start the pump. The PV array must be large enough to provide enough power to start the pump with including the head of water. The size of the PV array required for this method can be very expensive.

The first and most obvious way a VFD can save you money is through increasing the efficiency of your AC motors and decreasing electricity use. The amount of energy that a VFD can save depends on the average load of the motor and the number of hours per day it is turned on. While average energy savings vary, it’s safe to say that most AC motors do not need to be running at full capacity for most hours of their use. Furthermore, the initial cost of a motor or VFD is generally only a fraction of the cost of operating the motor over its life span. This means that a VFD system usually pays for itself in a matter of months or years.

Added advantages of VFD:

A VFD may be used for control of process temperature, pressure, or flow without the use of a separate controller. Suitable sensors and electronics are used to interface the driven equipment with the VFD.

• Lower maintenance costs, as lower operating speeds, resulting in longer life for bearings and motors.
• The motor does not require a starter.
• The ability of a VFD to limit torque to a user-selected level protects driven equipment that cannot tolerate excessive torque.
• Users can utilize multi-motor applications, such as pumps or fans, with one control unit.
• High-speed applications for the wood-finishing industry.
• Approx 30-40% energy is saved

How does it work?

A Variable Frequency Drive (VFD) is a type of motor controller that drives an electric motor by varying the frequency and voltage supplied to the electric motor. Other names for a VFD are variable speed drive, adjustable speed drive, adjustable frequency drive, AC drive, microdrive, and inverter.

Please contact Specialized Solar Systems for all you solar powered water pumping solutions today 044 878 1126

Specialized Solar Systems would love to hear from you.

Plan your move to energy liberation today with Specialized Solar Systems bestselling quality residential off-grid solar systems

Below are selections of our most popular and highly recommended residential off-grid solar powered energy systems with different sizing options designed by Specialized Solar Systems.  This selection of off-grid solar systems will give our customers an overview of all the quality equipment used with explanations to help assist you with your off-grid solar energy generation planning.

Other Solar Powered Systems:  Specialized Solar Systems Grid-Interactive Hybrid Solar Systems

Feeding-in to the Municipal Grid (Western Cape, South Africa)

Many municipalities across the Western Cape already have the rules and tariffs in place for feeding into the grid when installing a PV system. To view more information please view this link

Specialized Solar Systems Grid-Interactive Hybrid Solar Systems: The utility grid is a virtual battery
Electricity should be used as it is generated. However, it can be temporarily stored as other forms of energy (e.g. chemical energy in batteries).  Energy storage typically comes with significant costs.

The electric power grid is in many ways also a battery, without the need for maintenance or replacements, and with much better efficiency rates. In other words, more electricity (and more money) goes to waste with conventional battery systems.

Additional perks of being grid-tied include access to back up power from the utility grid in case extra power is required or if your solar system stops generating electricity for any reason.  At the same time, you also help to mitigate the utility’s peak load.

Customers can contact Specialized Solar Systems for more information on purchasing a Grid-Tied solar system and for expert advice when choosing the correct solar system solution for all your electrical energy needs.

To view a more detailed overview of our residential grid-interactive hybrid solar systems section in our catalogue available over here.

Below are selections of our most popular and highly recommended residential grid-interactive hybrid solar energy systems with different sizing options designed by Specialized Solar Systems.  This selection ofwill give our customers an overview of all the quality equipment used with explanations to help assist you with your off-grid solar energy generation planning.