P3 - Sustainable Energy Flashcards
A light bulb converts electrical energy into light energy and heat energy. If it has a power of 100W what does this mean?
It transfers 100J of energy every second
The total energy transferred by an appliance depends on how long the appliance is on and its power. What is the formula for energy transferred?
Energy transferred(J) = power(W) x time(s)
What is the formula for electrical power?
Power = Voltage x Current
Reducing heat transfer it stops energy being wasted. Give examples of ways to reduce heat loss
Installing cavity wall – and loft insulation, double glazing and draught-proofing.
How can you reduce the amount of it electricity you use?
You fishing efficient appliances and energy saving lightbulbs, as always by simply switching things off when you’re not using them. Also washing clothes at lower temperatures and turned on the heating can help.
What responsibilities do workplaces and the government to help save energy?
Work places can save energy by not printing and photocopying unnecessarily. They can also offer there employees incentives for using energy efficient ways to travel to work such as cycling or using public transport. Government can encourage people to save energy by offering grants better than installation, running schemes for trading in old boilers and more efficient ones and by improving public transport.
What does the power an appliance tell you?
How fast it transfers energy from the charge passing through it. Power is usually measured in watts(W) or kilowatts(kW).
What are non–renewable sources?
Fossil fuels: oil, natural gas. Nuclear fuels (uranium and plutonium). They do damage to our environment.
What are renewable sources?
Wind, waves, tides, hydroelectric, biofuels, geothermal, solar. They will never run out. They do damage to the environment but in less nasty ways than non-renewables.
How is nuclear energy made?
By nuclear fusion. In nuclear fusion, atoms in the nucleus of you – e.g. Uranium – are split into, releasing lots of heat energy. Water is then used as a coolant to take away the heat produced by the fitting process. This heat is used to produce steam to drive a turbine and generator. The generator converts the movement of the turbine - kinetic energy – into electricity.
What are the advantages of nuclear power?
Nuclear reactions release a lot more energy than chemical reactions and a nuclear power station doesn’t produce CO2 when making electricity. Also nuclear fuel is relatively cheap.
What are the disadvantages of a power?
It produces radioactive waste. – This can be very dangerous and it’s difficult to supposal this proposal as it emits ionising radiation and stays radioactive for long time. UK power needs extra safety precaution – waste needs disposing of carefully, and the surrounding area needs to be tested for contamination of the soil and water and workers need to be tested if they have been exposed to too much radiation.
