Padmashree Prof. Dr. P. K. Jena in Bhubaneswar, July 30, 2021: The industrial sector deals with production and processing of various types of goods. These include mining of minerals, extraction of metals and alloys, production of various types of organic and inorganic chemicals, refractories, cement, pulp and paper, manufacturing of various machines and equipment, agricultural implements, production of renewable and non renewable energy etc. For all these activities, a lot of energy is being consumed. Most of the energy used in industrial sector are being derived from fossil fuels which are limited in reserve and their cost is also escalating very fast.

In view of this, during the last 25 to 30 years, increasing efforts are being made to improve the efficiency of energy used in industries particularly in energy intensive ones. All over the world, research and development programmes have been taken up to bring better efficiency in energy consumption by using improved technology, developed equipment and reactors, recovering and using waste heat, better energy audit etc.

For example, in iron & steel and pulp & paper production, it has been possible to cut down about 40% of energy consumption. Similarly, in production of petrol, diesel, and aluminium smelting and cement production, it has been possible to reduce energy consumption by 25%. It is reported that, these energy conservation measures have largely been possible by recycling waste materials and using waste heat through co-generation equipment for electricity production and heating. The application of suitable high temperature insulation materials to drastically cut down the heat loss, is becoming important because of rise in cost of energy. It has been possible to reduce energy consumption to about 50% compared to old fashioned industrial insulation.

All over the world, energy consumption is increasing rapidly and it is estimated that during the period 2010 – 2030, its increase may be 33% more of the present figure. Worldwide industrial energy consumption is expected to increase by approximately 50% from 191 quadrillion Btu in 2008 to 288 quadrillion Btu in 2035. It is suggested that, by taking the following measures it would be possible to cut down the energy consumption to a large extent.

 Creating energy awareness,
 Facility to constantly monitor energy consumption,
 Effecting energy efficiency at all levels,
 Controlling Production,
 Energy Optimization and
 Energy Aggregation.

In most of the developing countries including India, the industrial sector uses about 50% of total commercial energy and in most of these sectors the energy consumption per unit production is much more compared to other industrialized countries. It is essential to take immediate steps to conserve substantial amount of energy by utilizing better technology, modern equipments and recovering the waste energy.

In industrial sector, the major consumers of energy are iron and steel, aluminium, fertilizers, textiles and cement industries. It has been estimated that, by taking various steps like using better technology and equipment, recovering the waste heat etc., it would be possible to conserve around 25% of energy used at present.

With upgradation of technology and modernization of various operations, introduction of control instrumentation and efficient energy audit, it would be possible to conservation energy appreciably. At the same time, the Government should also give fiscal incentives in various ways like reduction on import duty for specific items, giving tax benefits to energy saving devices and systems etc. As a result, it would be possible to encourage the industry to conserve energy resources.

For example, the coal industry is a source of energy as well as a consumer of energy. By using modern mining technology, better coal beneficiation process and efficient power production in modern thermal power plants, there is a great scope for reducing energy consumption. Similarly, in iron and steel, aluminium production as well as cement and other energy intensive industries, it would be possible to reduce energy consumption by adopting modern technology for production and heat recovery. In other areas like chemicals, pulp and paper etc., better technologies have to be identified and utilized in order to conserve energy. In general, the following three measures should be followed to conserve energy appreciably.

1) Formulation of administrative and informative programmes which are relatively easy to be implemented like tune ups, light turn offs, small adjustment in production process etc. These can reduce current energy consumption to the extent of 3 to 7%.

2) Re-equipping, retrofitting and recycling through small incremental investments for gaining about 10% saving of energy and.

3) Major production process changes through large scale capital expenditure for obtaining a saving from 20% to 30% gain, depending upon the nature of operations and facilities involved.

It is expected that the following five objectives can be achieved through energy conservation:

1) Reduction of imports of fossil fuels and thus curtailing drain on foreign exchange;
2) Improvement in exports of manufactured goods or energy or both;
3) Reduction of environmental pollution;
4) Reduction of the cost that pollution incurs and
5) Generally to relieve shortage of materials and effect further developments.

In order to achieve these objectives the following short term, medium term and long term measures are suggested.

1. Short Term Measures (Potential saving of 5% to 10% of energy)

 Meeting operational improvements requiring negligible capital investments
 Improved fuel storage, handling & preparation practices.
 Insulation of steam lines & pipes.
 Housekeeping & scheduling of process equipment.
 Minimizing radiation losses through opening
 Improved load factor.

2. Medium Term Measures (Potential saving of 15% to 20% of energy)

 Waste heat recovery.
 Installation of waste heat recovery devices.
 Reducing heat losses in furnaces with better insulating materials.
 Better instrumentation of furnaces & process house.
 Power factor improvement.
 Optimization.

3. Long Term Measures (Potential saving of 20% to 25% of energy)

 Fuel substitution, modernization of equipment, process as well as utilities, (capital intensive).
 Replacement of old inefficient boilers / equipment.
 Substitution of fuel oil to coal in boilers and other equipments
 Modernization of drives.
 Standardization.
 Use of correct size motors.
 Optimization.

By undertaking various measures as indicated above, it would be possible to save 20 to 30% of the energy consumed. The policy of the company in general should be from energy conservation to energy efficiency. In many industries, the employees lack in skills, knowledge about update technology and incentives to monitor and evaluate the energy used. They must be trained and given incentives to take enough care to reduce energy consumption in different areas of their operation. For example, the employees should take necessary steps to reduce consumption of water, air, gas, electricity and steam (WAGES) wherever possible in the system. Some important activities in this regard are as follows:

a) The first thing is to bring awareness among the workers to reduce energy consumption wherever possible.

b) Secondly, company should monitor and assess the facility level energy consumption and do the needful.

c) Lowering of energy uses is possible through scheduling production intelligently. For example, timing of the equipment change, over use of more efficient equipment and design improvements in order to use the waste heat.

d) The automation in industry can improve not only production safety but also energy conservation.

e) Energy management becomes more meaningful when the companies model, simulate and analyze energy as an economic factor.

In recent years, in order to make industry sustainable, all over the world various efforts are being made to bring down the energy consumption by adopting improved technology, using energy efficient equipments, reusing the wastes, conducting regular energy auditing, using trained personnel etc.

*Former Director General, CSIR, India