Energy Storage MCQ — 83 Practice Questions with Answers

Q1. Consider the following statements about policy measures for ESS in India: 1. Complete waiver of ISTS charges was made applicable to BESS and PSP projects commissioned up to 30 June 2025, subject to conditions. 2. The transmission charges after 30 June 2025 were to be increased by 25% every month until 2028. 3. Consumer rules asked users of diesel generator sets as essential backup to endeavour to shift to cleaner technology such as renewable energy with battery storage. 4. The Ministry of Power's March 2022 BESS procurement guidelines excluded ancillary services. Which of the statements given above are correct?

Q2. Consider the following statements about flow batteries: 1. Flow batteries involve two different liquid electrolytes that pass ions or protons through a porous membrane. 2. Their energy storage is fixed by a sealed internal cell, so increasing electrolyte tank size does not increase stored energy. 3. A vanadium redox flow battery uses two tanks of electrolyte solutions, one for the cathode and the other for the anode. 4. Flow batteries can be attractive because their energy and power can be changed independently. Which of the statements given above are correct?

Q3. Consider the following statements: 1. India needs hydro pumped storage projects to support faster energy transition with large-scale renewable integration. 2. CEA accorded concurrence to the 600 megawatt Upper Indravati pumped storage project in Odisha. 3. CEA accorded concurrence to a 2000 megawatt Sharavathy pumped storage project in Kerala. Which of the statements given above are correct?

Q4. Consider the following statements about classification and use of storage technologies: 1. MNRE lists mechanical, thermal, electrochemical, electrical and chemical storage systems as broad energy storage technology categories. 2. The most common type of energy storage in the power grid is pumped hydropower. 3. Lithium-ion is the only common chemistry for battery cells mentioned by DOE; lead-acid and sodium-based batteries are not common options. 4. Solar-plus-storage can provide backup power during an electrical disruption. Which of the statements given above are correct?

Q5. Consider the following statements about storage technologies and grid services: 1. Flywheel energy storage systems store kinetic energy in a spinning mass called a rotor. 2. A flywheel charges by applying a braking torque that decelerates the rotor and discharges by accelerating the rotor with a motor. 3. Many battery systems, flywheels and supercapacitors can provide rapid response from a few minutes down to fractions of a second for voltage and frequency quality. 4. Pumped-hydro, compressed-air and large energy-capacity battery systems can supply electricity consistently over several hours or more and are used mainly to moderate daily and seasonal demand variations. Which of the statements given above are correct?