(Mahida Hirenkumar Ranjitsinh)
Mechanical Engineering Department
Principles of Energy Conservation and energy
• Energy conservation means reduction in energy consumption but without making
any sacrifice quality and quantity of production.
• In other words, for the same energy consumption, higher production.
• It does not prevent you to use of energy by fixing some limits quantitavely within
the agreement but insists for use efficiently thus decreasing the cost of production
to some extent by way of reduction in the energy bill.
• Thus energy saved is the money earned which would be used in other productive
• It is therefore imperative that electricity which is in shortage, be utilized efficiently
and the areas of where the energy is wastefully used are to be identified and
corrective measures are searched for adoption. This could be done by “Energy
• Energy audit is a technical survey of a plant in which the machine wise, section
wise department wise pattern of energy consumption is studied and attempts to
balance the total energy input correlating with production.
• As a result of the survey , the areas where the energy is wastefully used and the
improvements are felt are identified and corrective measures are recommended
for adoption on short term / long term basis giving priorities so that the overall
plant efficiency could be improved.
• While doing so, a clear picture of financial involvement is given for each type of
recommendation measure supported by payback period to facilitate the easy
• Like capital, labour and material, energy is one of the production factors used e to
produce final goods and services.
• Energy conservation can be defined as the substitution of energy with capital,
labour, material and time.
• This definition also covers the substitution of scarce type of energy (oil) with
abundant type of energy (coal) or substitution of energy with convenience.
• There are mainly two principles for the governing of energy conservation.
1. Maximum thermodynamic efficiency
2. Maximum cost effectiveness in energy use.
• Energy conservation is the energy demand management that aim at increasing the
efficiency of use.
• An energy audit helps to understand more about the ways different energy sources
are used in the industry and helps to identify areas where waste can occur and where
scope for improvement may be possible.
• The energy audit would give positive orientation to the energy cost reduction,
preventing maintenance and qualify control programmes which are vital for
production and utilities activities.
• Energy audit is one of the concepts used in the energy management industries and it
involves methodological examination and comprehensive review of energy use in
• Energy audit is the starting point of energy management.
• Energy audit broadly covers the following questions.
1. How much energy are we consuming?
2. Where is the energy consumed?
3. How efficiently is the energy consumed?
4. Can there be improvements in energy use?
• The energy audits result in energy conservation proposals or projects. Initially the
proposal with minimum investment are identified.
• The criteria used for ranking proposals are saving obtained from a project
compared to the investment needed for achieving that savings.
• The energy measurement and energy monitoring are the basic necessary steps for
Types of Energy Audit:
• The primary objective of energy audit is to determine ways to reduce energy
consumption per unit of product output or to lower operating costs.
• The extent and the type of energy audit should result in gains commensurate with
• There can be two types of energy audit:
1. Preliminary Audit
2. Detailed Audit.
• The action plan towards the achievements of energy conservation through energy
audit may be drawn up into three phases.
1. Short term.
2. Medium term.
3. Long term.
Energy Conservation Approach/ Technology:
• Conservation of energy is using energy more efficiently by substituting time,
convenience, labour and capital, for effective optimization of costs.
• Steps towards energy conservation requires 3 level of efforts:
1. Formulation of administrative and information programme. (on the operators and
low level managers)
2. Re- equipping, Retrofitting and Re-cycling through small incremental investments
for gaining 5 to 10 % ( Middle level managers )
3. Major production process changes through large capital expenditure.