Past Paper Questions - Jan 2016 Flashcards
Explain the role that dispatchable generation plays in balancing supply and demand?
A generators output can be increased or decreased according to the level of demand of which can be brought on or offline, said to be dispatchable generation.
Give examples of dispatchable and non dispatchable generation.
dispatchable - Pumped hydro, gas turbines,
non dispatchable - Nuclear, Renewables
Why might demand side management be important in the operation of a low-carbon power system featuring significant quantities of wind power?
Adding wind power to the generation reduces the ability of the power system to match the demand and causes increased pressure on dispatchable sources.
Demand side management shifts some of the controllability to the demand, allowing demand to be modulated in support of network balancing.
Explain why the electricity transmission network is operated at extremely high voltage levels?
High voltage allows large quantities of power to be transmitted with low current flow and losses are minimised.
Explain why electricity is distributed to consumers at low voltage?
Supplying high voltage to consumers would be dangerous and require expensive equipment. Low voltages are therefore safer and cheaper. Losses are also small due to small power flows.
Where would salient pole generators be used?
Commonly used with hydro turbines, which have a slow speed of rotation and can also be used in wind turbines. These low speed rotors are always a large diameter to accommodate the large number of poles required. The poles are mounted on a large steel frame fixed to a revolving vertical shaft.
