Demand Side Management Questions and Answers

Answer: A

The utility acts on the demand rather than building supply to meet it, which can be the cheaper resource. Despatch, tariff approval and loss reduction are all supply-side or network activities with their own justifications.

Answer: B

A peak reduced by a hundred megawatts is a hundred megawatts of plant, transmission and distribution that need not be built, and the avoided cost is what the programme is judged against. It usually reduces sales, which is why the regulatory treatment matters.

Answer: C

Correct answer: the number of units it sells

Where revenue follows sales, every unit a consumer saves is revenue lost, so the utility is being asked to act against its own interest. Regulators address this by decoupling revenue from volume or by allowing the utility to earn on the savings, and without one of those measures voluntary programmes rarely amount to much.

Answer: D

Shifting a load from the afternoon peak to the small hours consumes the same energy and is a success for the utility, whereas conservation reduces the total. Both are demand side measures and only one reduces consumption.

Answer: A

Correct answer: reducing the demand during the peak hours

Peak clipping removes load at the peak and does not put it back, so the energy is not consumed at all. It reduces the capacity the system must carry, which is where the value lies, and it is achieved by direct control or by a price high enough to deter consumption outright.

Answer: B

Adding load at night improves the system load factor and spreads the fixed costs over more units, which is why night storage heating and off-peak vehicle charging are encouraged. It raises total consumption, which is the paradox of the objective.

Answer: C

Correct answer: moves the energy to another hour rather than removing it

Shifting leaves the total energy unchanged and only its timing altered, which suits loads that must run at some point - a batch process, a water heater, a vehicle charger. Clipping removes the energy, which suits loads the consumer can genuinely do without for an hour or two.

Answer: D

Promoting electric vehicles charged overnight, or electric heat displacing oil, adds sales in the hours the system is idle and uses assets already built. It is the one objective that increases consumption deliberately.

Answer: A

Contracts with interruptible consumers give the operator a resource to call on at short notice, which is worth more as intermittent generation grows. It is the objective that has become most valuable in a system with large renewable capacity.

Answer: B

The three are distinguished by whether energy is removed, added or merely moved, and each has a different effect on the utility's revenue as well as on its capacity requirement. Confusing them produces programmes that miss their intended benefit.