2. Types of energy
There are two major categories of energy resources:
Non renewable ( finite, stock or capital resources)
•
fossils fuels e.g. Coal, oil, gas and nuclear.
•
These energy sources have built up over time.
•
Once the stock has been used up, there is no more due to the slow rate of
formation.
Renewable (flow or income resources)
•
Solar, HEP, geothermal energy, wave/tidal power, wind power and biomass
•
Yield a continuous flow that can be consumed in any given time period
without endangering future consumption, as long as current use does not
exceed net renewal during the same period.
4. Renewable energy can be subdivided
Critical:
Sustainable energy resources from forests, plants and animal waste which require management
Some renewable resources may be depleted by heavy use or misuse. The lifestyle of the
resources is restricted e.g. Wood. Wood is a renewable resource however critical because
trees take a while to grow and if there is heavy usage then the stock may be depleted.
Non-critical:
Everlasting resources such as tides, waves, running water and solar power
5. Primary & secondary
Primary resources can be renewable and non-renewable:
Primary energy is released from a direct source. E.g coal, oil, wood
and Uranium.
Secondary energy is primary energy converted into a different
form e.g. When heat energy is used to generate electricity or
Petrol.
Secondary energy tends to be for commercial and industrial use.
This is increasing due to urbanisation.
6. Energy mix- UK
Describes the combination
of primary resources a
country uses
Now
Coal: 17.7 % (fall)
Oil: 31.9% (fall)
Gas: 42.3% (rise)
Nuclear: 7.6% (rise)
7. Energy mix more detail- UK
non renewable
The depletion of oil and gas reserves has caused
the UK to depend on imports. In 2004, the UK
became a net importer for the first time since
1993.
2005:
* 76% energy from fossil fuels
*19% Nuclear
*4.5% renewable
RENEWABLE ENERGY
FACTS
82% of renewable energy
was biomass (2006)
Aim: by 2020, 20% will be
renewable energy