Power Generation/Introduction/Intro 2

Energy is defined as the ability to do work. We can simplify the forms in which we encounter energy in our daily life into three forms as follows:

1 Mechanical energy (Measured in N.m → Newton-meter = Joule):

• Ability to move things.

2 Thermal energy (Measured in Cal or KCal → Calorie or Kilocalorie):

• Ability to heat things.

3 Electrical energy (Measured in Watt.sec → Watt-second):

• Ability to use electricity to do work.

All the above forms of energy are interchangable since they can be used to do work and thus can be expressed using the same unit of measurement. The Joule!. The following table summarizes the relationship among energy units

Table 1:relationship among energy units

Energy form Comparison	Unit	Calorie equivelence	Joule equivelence
Heat→Mech	.	1 calorie	4.18 Joules
Heat→Mech	1 C.H.U	453.6 calories	1896 Joules
Heat→Mech	1 B.TH.U	252 calorie	1053 Joules
Elec→Mech	1 Watt.sec	0.24 calories	1 Joule
Elec→Mech	1 Kwh	860 KCal	$3.6\times 10^{6}$ Joules

Calorific value of fuels

The following list of external sites shows a comparison of various types of common fuels and their calorific value:

1. Calorific values at wikipedia
2. Calorific values at kaye & labby

Comparison of Solid fuels v/s Liquid fuels

Table 2: Comparison between Solid fuels and Liquid fuels

Solid Fuels	Liquid Fuels
Cheap	Expensive
Minimal odours	unpleasant odours
Requires simple burners	requires sophisticated burners
No climate constraints	Cold climates need regulation