OCR Gateway P2d

Question	Answer
P2d - Fuels for Power	.
Important equations	Power = Voltage x Current Energy Supplied = Power x Time Cost of Electricity used = Energy used x cost per kWh
Fuels for power stations	The common fuels used in power stations include: fossil fuels (coal, oil and natural gas) nuclear fuels (uranium and, sometimes, plutonium) renewable biomass (wood, straw and manure). Each type of fuels has advantages and disadvantages.
The National Grid and transformers	A transformer is an electrical device that changes the voltage of an AC supply. A transformer changes a high-voltage supply into a low-voltage one, and vice versa. A transformer that increases the voltage is called a step-up transformer. A transformer that decreases the voltage is called a step-down transformer.
The National Grid	When a current flows through a wire, some energy is lost as heat. The higher the current, the more heat is lost. To reduce these losses, the National Grid transmits electricity at a low current. This requires a high voltage.

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	Created by Zaaaara almost 10 years ago