Question 25 from UPSC CSE 2020 - S&T

Question

With reference to solar water pumps, consider the following statements:
1. Solar power can be used for running surface pumps and not for submersible pumps.
2. Solar power can be used for running centrifugal pumps and not the ones with piston.
Which of the statements given above is/are correct?

IASCODEX · Accepted Answer

Correct Option: D. Neither 1 nor 2

Strategy: - Statement 1 is incorrect: Both surface and submersible pumps can utilize solar power, as their classification relates only to installation location, not power source compatibility.
- Statement 2 is incorrect: Solar electricity can drive various pump types, including common centrifugal pumps and less common piston-type (positive displacement) pumps, demonstrating solar's broad applicability.

Key Info: ## Solar Water Pumps

Solar water pumping systems convert solar energy into electricity using photovoltaic panels to power electric pumps for water supply or irrigation.

### Pump Types

The two main categories are centrifugal (rotodynamic) and positive displacement pumps (such as piston, diaphragm, screw, and vane pumps). Both types can use solar-generated electric motors for operation.

### Centrifugal Pumps

These pumps impart velocity to water using a rotating impeller, suitable for high flows at lower heads. Widely used in agriculture and for open-well irrigation, centrifugal pumps can be either surface-mounted or submersible, and solar-powered variants are common.

### Positive Displacement (PD) Pumps

These mechanically move fixed volumes per cycle, suitable for high-head, low-flow applications. Piston, diaphragm, and helical rotor (screw) pumps can all run on solar-powered electric motors.

### Surface vs. Submersible Pumps

Surface pumps are installed above the water source, suitable for shallow water levels, while submersible pumps operate beneath the water, suited for deep wells. Both configurations can be powered by solar electricity, provided the pump's energy demands match the available solar capacity.

### Applications

Solar water pumps help provide decentralized, off-grid water supply for drinking water, livestock, and agricultural irrigation, reducing reliance on diesel or grid power and supporting rural development.

### Government Programs

India's Ministry of New and Renewable Energy (MNRE) promotes solar pumps under schemes like PM-KUSUM, offering financial assistance. These programs support both surface and submersible pump varieties.

### Selection Criteria

The choice of pump type and installation depends on well depth, required discharge, and head. The electrical/acoustic demands of either centrifugal or positive displacement (like piston) pumps can be met by appropriately designed photovoltaic systems.

IASCODEX · Answer

Option A: 1 only

IASCODEX · Answer

Option B: 2 only

IASCODEX · Answer

Option C: Both 1 and 2

With reference to solar water pumps, consider the following statements: Solar power can be used for running surface pumps and not for submersible pumps. Solar power can be used for running centrifugal pumps and not the ones with piston. Which of the statements given above is/are correct?

With reference to solar water pumps, consider the following statements:

Solar power can be used for running surface pumps and not for submersible pumps.

Solar power can be used for running centrifugal pumps and not the ones with piston.
Which of the statements given above is/are correct?