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?

The correct option is Neither 1 nor 2.

Let us analyze the statements step-by-step to understand why both are incorrect:

Analysis of Statement 1: "Solar power can be used for running surface pumps and not for submersible pumps."
Solar photovoltaic (PV) systems convert sunlight into electricity, which can run an electric motor to pump water. This electrical energy can be supplied to any type of electric motor, whether it is installed on the surface (surface pumps) or submerged deep underground in a borehole or well (submersible pumps). Therefore, solar power is routinely used to run both surface and submersible pumps. Thus, Statement 1 is incorrect.

Analysis of Statement 2: "Solar power can be used for running centrifugal pumps and not the ones with piston."
Similarly, the motor powered by a solar PV system can drive various types of mechanical pumps. Centrifugal pumps (which use rotating impellers) and piston pumps (reciprocating positive displacement pumps) can both be coupled to solar-powered motors. Piston pumps are particularly useful in solar applications where high head (pressure) and low flow rates are required. Therefore, solar power can be used to run centrifugal pumps as well as piston pumps. Thus, Statement 2 is also incorrect.

Since both Statement 1 and Statement 2 are incorrect, the correct option is "Neither 1 nor 2".