Energy services, Electrical Energy Conservation, Electrical energy audits, Energy Conservation Cement and allied process plants,

ELECTRICAL ENERGY CONSERVATION IN CEMENT PLANTS

SUMMARY

"Energy Audit" is an effective control device for supervision and guidance of energy utilization. Conservation of energy means to save energy and avoid waste i.e., a more rational and scientific use of energy in order to reduce its amount to accomplish a given task. Energy Conservation is the need of the hour. It strengthens a Nation, and also industries and individuals.

In the changing industrial scenario, Energy Conservation Movement is picking-up, setting every cement plant its own norms keeping in comparison with identical plants. The Energy Conservation is a never-ending process, and may be continued for bringing down the Specific Power Consumption (SPC) levels lower and lower using the WILL POWER.

PREAMBLE

With spiraling costs of all inputs, most of which have fiscal controls, the Technocrats in major Industries all over the World continuously aspire for Energy Conservation, which is a never-ending game, but with profits all the time for better conservation. Whilst Energy would refer to both Electrical and Thermal or Fuel, we shall restrict our discussions here to 'Electrical Energy', which is acclaimed as panacea for all ills in Industries in the Country. Apart from the problem of getting uninterrupted and reliable supply, what is most pathetic is the "quality" of the power dished out by the Electricity Boards with the motto - "take it or leave it" . To the Technocrats it is always a loosing and frustrating game. In this scenario one can do no better than Conserve the available Energy, and it has to be understood and practiced from the Board Room to the shop floor. 'Efficiency' is doing a thing right, but 'Effectiveness' is doing the right thing right, and Energy Conservation is the most Effective tool for minimizing the power costs.

Presently about 70% power generation is from Thermal sources, mainly by burning Coal. Although, we have at present enough Coal deposits to last for next 100-150 years; the major problems are huge amount of CO2 generated, resulting in serious Green House effects world over and unsatisfactory disposal arrangements for millions of tons of fuel ash generated.

POWER ADVANTAGE GIVES YOU THE EDGE OVER YOUR COMPETITION

Your facility's Electricity Costs are a steady drain on your Company's bottom line. Most business Executives tend to view the Electricity Costs as an unavoidable budget line... something that has to be paid, but little can be done to reduce.

ENERGY SERVICES GROUP (ESG) is ready to show you a way to break free of the burden of these high Electricity Costs. And, just as our program has helped many manufacturing units in AP and neighboring States to find new profits where they had previously only seen a 'Fixed' cost, ESG can immediately put this new money back where it belongs for you...

It is important to understand that you already are forced to Budget to a steady, non-negotiable 'Fixed' expenses each and every month...Your Electricity Bill. This money is already in your budget, your cash flow projections, and anticipated in your P&L Projections.

By implementing an ESG Efficiency System, these planned costs would immediately plummet, by 5 to 10% or even more. That is real cash-in-hand you did not plan to have. ESG's work is paid for from this new cash.

You depend on your Electrical Equipment to operate without any interruptions and on peak performance, and for as little ongoing cost of maintenance and repair as possible. That's why ESG only recommends and implements effective Efficiency Solutions that improve the System Efficiency of your Plant.

YOUR MACHINERY & EQUIPMENT WOULD THEN RUN BETTER AND LAST LONGER.

By exactly tailoring the input electricity to the needs of each individual electrical device ESG would attend to, all of them would run cooler, last longer, have fewer incidences of failure, and require less unplanned maintenance.

ELECTRICAL ENERGY CONSERVATION:

Electrical Energy Conservation is a process comprising of:

Measurement of running load parameters of all the individual motors / equipment.

Analyzing the Data collected and measured for the possible Energy Conservation by various methods.

Implementing the recommendations derived from the analysis for positive results.

Based on the cost for implementation and the payback period the Energy Conservation methods may be classified as:

ZERO COST METHOD - Where the payback period is immediate and there is no cost involved for implementing

the Energy Conservation method.

LOW COST METHOD - Where moderate cost will be incurred to achieve the saving and the pay-back period is

less than 2 months

MEDIUM COST METHOD - Where the cost for implementation will have a payback period of 2-12 months.

HIGH / CAPITAL COST METHOD: In this method purchase of capital items to replace the existing one is

recommended and the payback period will be more than one year.

ZERO COST METHOD:

Energy Services Group has identified very good potential for Electrical Energy Conservation by Zero Cost Method.

The measures to be taken to ascertain the quantum of Energy Conservation are:

Measurement of the Running Load Parameters of all the individual motors.

Measurement of H.T & L.T incomer and distribution network Branch Loads

Measurement of incoming & outgoing of Power Transformer Load Parameters

Study of Capacitor Distribution for uniform Power Factor.

Generally Cement plants drive motors are over sized during the design to take care of any deviations that may defer from the calculations. Once the plant has been commissioned the over sized motors cause lower efficiency. It is also not practicable to fix all motors to the rated design for high efficiency.

In some plants the higher rated motors have been replaced by smaller capacity ones to achieve saving by increasing the percentage load on the motor and its efficiency. But in most cases with materials handling equipment viz., belt conveyors, elevators, screw conveyors one has been forced to revert back to original designed motor, as the reduced size of the motor was not able to meet the starting torque requirement of the loaded conveyor.

Without replacing with a smaller capacity motor the efficiency can be improved by effectively tuning the load parameters to the optimum. This has to be done by closely monitoring the characteristics and running load parameters of all the motors in the network distribution.

Tuning the Load Parameters to the optimum reduces Energy Consumption considerably and also results in prolonged life of the Machinery.

LOW COST METHOD:

This method mainly deals with uniform distribution of Capacitors by connecting across motors and re-location of Capacitor banks for achieving reduction in transmission and distribution losses. The low cost is due to present capacitor banks re-location / modification / cable layout / manpower cost etc., which can save considerable amount of Electrical Energy and the payback period will be less than 2 months.

During the Energy Audit the ESG will be noting the Power Factor at all branches of the network distribution. In most of the cases whilst the overall Power Factor of the plant may be found to be good, in the branch /section-wise there would be lot of deviations. For better and uniform Power Factor section wise Capacitor requirement should be calculated and the existing Capacitor banks re-arranged. Due to Capacitor re-arrangement the Power Factor from load end will improve uniformly all over the plant which in turn would reduce the flow of current thereby minimise the copper losses / heat losses.

POWER CAPACITORS CAN BE USED FOR

Improving the power factor, and Reducing energy losses in the power network distribution.

It has been observed that in many plants the Capacitors usage is limited to P.F improvement on overall basis so that the penalty for poor System P.F can be avoided. If the Capacitors are uniformly distributed in the plant according to the load, the overall P.F will be very good and also considerable energy saving can be achieved due to reduced current flow in the power distribution branches, there by reduced heat losses also.

With negligible cost the capacitors can be rearranged for getting the benefit of energy conservation by reducing or minimizing the transmission and distribution losses.

It is beneficial to improve Power Factor from the load end, so that the improved Power Factor reduces current flow in the circuit, thereby minimizing the copper / heat losses.

MEDIUM COST METHOD:

This deals with improvement of Power Factor by procuring New Capacitors to minimize the losses and introduction of various Energy Saving Devices that may be made to suit the equipment requirement. In this method the Cost incurred for the Energy conservation will have a payback period less than a year. In some cases where the fan outlet damper opening is less than 60% in normal operation the reduction of motor speed by Variable Frequency Drive, will save lot of energy, where the payback period will be less than a year.

HIGH / CAPITAL COST METHOD:

For implementing this method the plant has to procure New Equipment / Starters viz., Variable Frequency Drives, Lighting Energy Savers, Installation of high efficiency motors, Replacement of Air Lifts with Bucket Elevators etc., The payback period for high / capital cost method will be more than one year.

SCOPE FOR ENERGY CONSERVATION BY VARIOUS METHODS:

Zero Cost Method: The scope will be 3 to 6% of the overall power consumption.

Low Cost Method: The scope will be 0.5 - 1.0% of the overall power consumption.

Medium Cost Method : The scope will be 0.2 - 0.5% of the overall power consumption

Capital/High Cost Method: The scope will be 0.1 - 0.3% (This does not cover the process modifications or plant

up-gradation or Technological improvement by R&D)

Due to increasing cost of Electric Power most of the plants have procured already the items coming under Medium & High cost methods and installed, leaving very less scope in these areas for further Energy Conservation. It has been observed that there is a very good scope for Electrical Energy conservation by Zero / Low Cost methods, in which the cost for implementing the same is negligible compared to the saving.

ENERGY SERVICES GROUP

The "ENERGY SERVICES GROUP" (ESG) was founded in May 1998 by a group of Well - Qualified Electrical Engineers with vast experience both in India and overseas in large sized Cement Plants.

ESG's primary function is to provide Services for optimizing the Electrical Energy Utilisation by various practically proven and time-tested methods, by reducing Energy Wastage.

ESG has specialized in reducing Power Consumption by tuning of the load parameters of the Machinery / Equipment in Cement and Allied process industries.

ESG have done Detailed Electrical Energy Audit in many reputed major & mini Cement Plants and allied process plants all over India and the findings and recommendations have been well received, and implemented to reduce the Total Power Consumption and so save Energy.

ESG has state-of-the-art type specialised instruments for Measurement of the running load parameters of all the electrical equipment and motors in the plant, which help in arriving at innovative ideas for Energy Conservation.

On Implementation of ESG recommendations for Optimizing Electrical Energy Consumption, the Energy Saving can be noticed clearly from :

The Daily Power Consumption Report.

Units / hour consumption and

Instantaneous changeover from the tuned parameters to earlier parameters.

Arriving at the optimum operating load parameters need a lot of study and monitoring whereas maintaining the tuned optimum load parameters will be very easy and simple. Due to the fine-tuning of the load parameters the life of the machinery increases apart from the considerable Energy Conservation.

CONCLUSION

There is a good potential for reducing Power Consumption by optimizing the utilization of Electrical Energy by tuning the load parameters to suit the requirement. Every unit saved is a unit generated. Looking to the substantial capital involved in the generation and transmission of energy, it is necessary to reduce losses of every kind to the best possible extent, by making Energy Audit a routine rather than a one time exercise.

ESG's experience in conducting Energy Audits and tuning operational load parameters for optimizing Electrical Energy Utilisation, indicates that about 5-10% of Energy can be saved by Zero and Low investments by implementing the optimization of running load parameters by fine tuning and by improving the Power Factor of the entire plant by redistribution of the Capacitors maintaining uniform Power Factor in all the branches of the Power Distribution Network, at all varying load conditions.

In the changing industrial scenario, Energy Conservation Movement is picking-up, setting every Cement Plant its own norms keeping in comparison with identical plants. Energy Conservation is a sacred objective since it results in achieving increased long lasting resources of energy apart from the reduction in production cost. Minimizing the wastage is a continuous process, in which cumulative efforts are involved for bringing down Specific Power Consumption levels lower and lower.