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CHAPTER II LITERATURE REVIEW
2.1 Demand of electricity
2.1.1 Demand
Demand means the quantity of a given article which would be taken at a
given price. Supply means the quantity of that article which could be had at that price. Defines that demand is the amount of a particular economic good or service
that a consumer or group of consumers will want to purchase at a given price. The demand curve is usually downward sloping, since consumers will want to buy
more as price decreases. Demand for a good or service is determined by many different factors other than price, such as the price of substitute goods and
complementary goods. In extreme cases, demand may be completely unrelated to price, or nearly infinite at a given price. Along with supply, demand is one of the
two key determinants of the market price Aemo, 2012.
2.1.2 Electricity
According to electricity is the set of physical phenomena associated with the presence and flow of electric charge. Electricity gives a wide variety of well-
known effects, such as lightning, static electricity, electromagnetic induction and electrical current. In addition, electricity permits the creation and reception of
electromagnetic radiation such as radio waves. While based on. electricity is a form of energy resulting from the existence of charged particles such as electrons
or protons, either statically as an accumulation of charge or dynamically as a current.
Based on both describtion of demand and electricity, we could take a conclution to give the meaning that electricity demand is the amount of electricity
being consumed at any given time Aemo, 2012. Electricity supply is instantaneous, which means it cannot be stored and
supply must equal demand at all times. Electricity demand is measured by perpustakaan.uns.ac.id
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demand this way is that it includes electricity used by customers, energy lost transporting the electricity network losses, and the energy used to generate the
electricity auxiliary loads.
Figure 2.1- shows the high-level topology of the electricity transmission network connecting supply generation and demand customers Aemo, 2012
It also shows the different points at which supply and demand are measured as well as the relative contribution of different types of generation.
The electricity energy supplied by a generator can be measured in two ways: Aemo, 2012
a Supply „as-generated‟ is measured at the generator terminals, and represents
the entire output from a generator. perpustakaan.uns.ac.id
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Supply „sent-out‟ is measured at the generator connection point, and represents only the electricity supplied to the market, excluding a generator‟s
auxiliary loads. c
The basis for projecting energy and maximum demand d
Energy is presented on a sent-out basis. This means that the energy projections include the customer load supplied from the network and
network losses, but not auxiliary loads. e
Maximum demand is presented on an as-generated basis. This means that the maximum demand projections the highest level of instantaneous demand for
electricity during summer and winter each year, averaged over a 30-minute period include the customer load supplied from the network, the network
losses, and the auxiliary loads.
2.1.3 Power distribution system