Promoting energy efficiency in industries:

technologies and case-studies

CTCN Regional Forum for NDEs

Prosanto PalTERI, New Delhi

prosanto@teri.res.in

UNCC, Bangkok

11-13th July 2016

Why energy efficiency

Improving energy efficiency is the

cheapest, most effective and least

politically controversial way of

achieving sustainable energy

consumption in the future

Improving energy efficiency is the

most important means to mitigating

climate change

According to the IEA (International

Energy Agency), improving energy

efficiency must account for more than

50% of the measures needed to win

the battle against global warming

Option Payback,

years

Solar 10-15

Wind power 20-30

Energy efficient

equipment

2-5

Adoption of

energy-efficient

options

Process

technologies

Cross-cutting

technologies

Fuel switch

options

Recycling and

use of secondary

materials

Melting/heating

Drying

Evaporation

Distillation

Pumps

Fans

Compressors

Air conditioning/ refrigeration

Drive motors

Natural gas

Biomass

Awareness creation/capacity

building/knowledge sharing

Performance assessments for identification

of potential energy efficiency options

Incubating (developing & demonstrating)

EE technologies (for SMEs)

Technical assistance during

implementation of recommendations

Financial linkages (bankable DPRs)

Common types of response plans

and implementation support

‘Areas’ and ‘Levels’ of energy efficiency

improvement

Area 1

Plant auxiliaries

Area 2

Process

Level 1

Good housekeeping

measures

Reduce leaks (air,

steam etc)

Furnace

operation

Level 2

Retrofits and

revamps

Install variable

speed drive

Install

WHR

Level 3

New plant or process

designs

Install new

equipment

Install new

furnace

Energy audits

First step in identifying energy efficiency

improvements

Involves technical and economic study of major

potential areas/ applications for saving energy in an

industry

Actual plant measurements/data are taken wherever

possible

Inadequate plant instrumentation and inaccessibility

for measurement may be a challenge

Level 1: Good housekeeping

measures

Damper adjustment

Before:• O2 level – 9.2%• Dry flue gas

losses –4.03%

After:• O2 level – 3%• Dry flue gas losses –

2.6%• Annual NG savings –

2252 SCM• Payback period – 2

months

1 tph natural gas fired boiler

Plug compressed air leakages

Energy saving 7%

Before After

17% compressed air leaking observed out of

260 cfm generation

Leakage was plugged to minimize the losses

Reduce bends in compressed air network

Energy saving 3%

Before After

Multiple bends were observed in compressed air network

Network piping was modified to reduce bends

Level 2: Retrofits and revamps

Reheating Furnaces in steel rerolling mills

in Indonesia

Technology - pusher hearth type furnace

Fuel used: Natural Gas

Accounts for 85% of total energy

consumption

Efficiency of furnace is 49.6%

Primarily reasons for poor efficiency

Poor automation and control system

High dry flue gas losses

Poor insulation and damaged refractory

Poor loading

Automation and control system to

improve Air to fuel ratio in reheating

furnace

Avoid the heat losses from

combustion air supply

Improve thermal insulation of

furnace

Optimization of furnace zones and

billet temperature

EE technologies

Support during implementation:

Ceramic module for relining

Energy saving 7%

Before After

9.5% loss was observed in brick

lined gas-fired shell baking

furnace

A layer of ceramic module was

retrofitted to bring losses down

to 2.4%

Change of burner change

Before• CO level – 94000 PPM• Dry flue gas losses –

18.5%

After• CO level – 0 PPM• Dry flue gas losses – 5.1%• Simple payback period – 1

year

Replacement of oil fired boiler –with same fuel

Before• Efficiency – 58%

After• Efficiency – 85%• Payback period – 3 years

Replace inefficient compressor with efficient ones

Energy saving 26%

Before AfterTwo belt-driven piston-type air compressor

to meet compressed air demandReplaced with a screw compressor with

variable frequency drive

18

Replace old pumps by energy efficient pumps

Level 3: New plant/process designs

Energy efficient glass furnace with

WHR for SMEs in India

Power generation from Waste Heat

in FeSi plant in Bhutan

Parameters Unit ValuesFlue gas exhaust temperature - at hood 0C 460Flue gas flow rate kg/hr 87,342Waste heat energy available kcal/hr 8,638,168Power generation potential MW 3.3Payback years 3

Submerged Electric Arc Furnace 18 MVA