DT Flashcards
what are the types of finite energy sources?
- turbines and generators
- fossil fuels - finite
- shale gas and fracking
- renewable energy sources
- wind turbines
- solar energy
- tidal energy
- biofuel
- hydroelectric power (HEP)
- nuclear power - radioactive
definition of turbines and generators
Process:
fossil fuels are burned to create heat that superheats the water. the steam is then used to rotate turbines which are linked to a generator to provide us with a supply of electricity
definition of fossil fuels (finite)
most heat we use to generate electricity is from fossil fuels (coal, oil) these are finite resources as they were formed over many millions of years and cant be replaced if run out.
definition for shale gas (+ fracking)
a natural gas that is trapped within areas of shale in the Earths crust.
Fracking is the controversial process of extracting gas from the shale
EXTRA:
- shale is sedimentary rock that can be rich in petroleum and natural gas.
- fracking is drilling into earths crust and sending high pressure water sand and chemical mix into rock to release trapped gas, which travels up drilled shaft and collected at well head.
definition for renewable energy sources
energy that comes from planets non finite resources is considered to be renewable
(wind, wave and tidal, hydroelectric, geothermal, biomass and solar energy)
definition for wind terbines
produce more power in winter moths when demand is higher but have some drawbacks. do not produce power when not windy or when too windy, can harm wildlife and not aesthetically pleasing.
are however a relatively cheap option
definition of solar energy
The photovoltaic cells captures sun rays and coverts them into electrical energy. the cells only produce energy during the daytime and production is less in winter.
definition for tidal energy
relies on movement of water to turn turbines which drive the generators that produce electricity. There are different varieties. benefits include more predictable and more consistent energy production but repairs and maintenance are difficult due to areas in which they need to be located
definition of biofuel
oil and starch producing crops are grown, harvested and refined into a number of products including biodiesel. The process is known as biomass energy productionn. The term biomass can include other solid biofuels ie wood chips and farm waste.
definition of hydroelectric power (HEP)
A reliable source of renewable energy. has high initial set up costs both financially and environmentally as vast area of land needs to be flooded to create a reservoir. more efficient during heavy rainfall
definition of nuclear power (radioactive)
considered a clean and efficient energy source although controversial. provides over 11% of world’s electricity. process harnesses nuclear reaction that takes place inside reactor vessel. control rods are moved in or out of reactors core to regulate amount of power generated. reaction generates vast amounts of heat which superheats water and generates power by driving turbines and generators.
definition of composite materials
a type of material that is formed when two or more different materials are combined to create a new material with improved properties and functionality. E.g. concrete
examples of composite materials
- glass reinforced plastic (GRP)
- carbon fibre reinforced plastic (CRP)
- Technical textiles
- Gore-Tex (condensation)
- Kevlar - aramids
- conductive fabrics: e-textiles
- heat resistant fabrics / flame retardants
- microfibres and micro-encapsulation
gears and ratios
key factors
- if two gears are touching the gears (teeth) engage with the teeth on other gear - how driver gear runs and makes driven run
- if driver gear is running in one direction, the driven gear will be rotating in the other direction (opposite)
