The solar water pump system is composed of PV array, solar pump Growatt inverter and water pump，which has become very popular as an environment- friendly, pollution-free and economical water lifting system in recent years.
Getting access to a safe and sustainable water supply causes growing concern in the world. In many communities, groundwater is pumped by diesel-fueled systems which are expensive and difficult to maintain. While in some communities with insufficient power supply, the solar water pump system can help up this point.
The solar water pump system is in the greatest demand among rural off-grid areas where lift water by water pump fueled by expensive gas energy. And it is the most competitive water lifting system in regions with abundant solar energy such as the Africa, South America, and Asia. Furthermore, this technology can be applied in almost any region of the world where there is sunshine.
There are many application scenarios like photovoltaic drought resistance, desert oasis irrigation, desert management, livestock water, agricultural irrigation, household water storage, etc.
The working principle of the system is easy to operate. The solar pump Growatt inverter converts the DC power from solar panels into AC power, then drives the AC pump to lift water from the well. The solar water pump system features safe and reliable, energy-saving and environment-friendly, high-standardized and easy maintenance, high-compatible, which also realize unattended and fully automatic operation. It is replacing older diesel water pump systems in many areas for reasons of non-polluting and economy.
Below we mainly introduce the solar water pump inverter that is the core device of the solar water pump system.
Solar water pump inverter is one of the inverters same as the on-grid inverters, converting the solar panel generated DC Power into AC Power. Furthermore, the solar pump inverter has been progressed aiming at the pump load, thus saving the whole system cost greatly.
Actually solar water pump inverters belong to off-grid inverters independent from grid and work independently with load. While the regular off-grid inverters have to work with batteries. Lead acid batteries are expensive but with short lifespan for 3-5 years, and its cost accounting for 30% of the system cost, thus affecting the ROI of the solar water pump system. The solar water pump system can work without a battery and support working when there’s sunlight. A water tower is built in a place at high altitude to get water when needed. The pump inverter itself is equipped with a water level switch to control the start or stop of the system automatically, which is very convenient and practical. The water tower is equivalent to the battery in an off-grid system, but its cost is much lower than the battery.
Electric motors is one of the most difficult driving loads for off-grid system because its startup current is high. The startup current of a regular motor is about 3 times that of its rated current. While the pump motor needs to lift water to a high place, and the starting current is about 5 times of its rated current. Therefore, if an off-grid inverter works with a pump motor, its power needs to be amplified by 5 times.
For example, a 2kW pump needs to be driven by a 10kW off-grid inverter, thus will bring the increase of the system cost. However, the solar water pump inverter’ power only needs to be increased by 20% higher than the pump power rating. For example, a 4kW pump can be driven by a 5kW solar water pump inverter. During system working, when the PV input power islessthan 4 kW or even around 1kW, the pump still continues to work.
Why is the solar water pump Growatt inverter so powerful?
The pump can also be started at a low frequency. The rated operating frequency of the regular pump is 50HZ or 60HZ, but it can also be started at 10HZ to lift water.
The solar water pump inverter also features the inverter function which can change the AC output frequency. Even if the PV input power is very weak, the solar water pump inverter will decrease the output frequency. A 4kW water pump can operate at a low frequency state even under 1kW PV input. When the light is sufficient, the pump inverter will run at a full frequency state as well as the water pump will output at full load.
Should consider various parameters while design a solar pump system:water demand (volume), water storage, water depth (head), location of PV panels, and solar irradiance among others. Fortunately, some software provides a free and user-friendly tool that enables engineers to design and make sure the size of solar pumping system easily.
Growatt SPI 750-4000TL2-HV series solar water pump inverter is a new generation of photovoltaic water pump inverter launched recently, with a power range of 0.75-4kW and a rated output voltage of 220Vac. Support Single phase and three phase 220V AC water pumps, IP65 protection grade suitable for outdoor installation. Also have the following advantages:
- MPPT control method
- Automatic running
- Remote control by APP
- Support pump soft start protection function
- Equipped with lower water level detection
- Dry protection
- Water level sensor function
- Support DC and AC Simultaneous input
- Built-in boost module