Industrial Utility Efficiency    

Manitoba Hydro’s Performance Optimization Program

 

Good morning. Please describe Customer Engineering Services at Manitoba Hydro.

Good morning. We are part of the Industrial and Commercial Solutions Division which is part of the Customer Care and Marketing Business Unit at Manitoba Hydro. Customer Engineering Services has a staff of approximately 35 people. Our role is to provide value added engineering services to help our industrial and commercial customers use the power we produce more wisely – with a high priority given to energy efficiency.

 

What is your role?

My role is to assist customers in optimizing their compressed air systems, this occupies my time almost exclusively, as well as one of my collegues. I work with Hydro’s Performance Optimization Program. It mainly deals with systems using motor driven rotating electrical machinery, with some process optimization. A few years ago we added a natural gas program to our portfolio.

 

Please describe the Performance Optimization Program and why it’s been so effective.

The Power Smart Performance Optimization Program provides industrial and large commercial customers with the technical support and financial incentives that are necessary to identify, investigate and implement system efficiency improvements throughout a facility. The program promotes energy efficiency through the optimization of three phase electrical power end-use systems including compressed air, pumps and fans, industrial refrigeration, process heating, electro-chemical processes and plant-wide energy management systems. The result is lower operating costs and improved system performance.

The network of contacts we maintain is key reason why we do so many projects with compressed air systems. In the compressed air market, you have to be there in the mind of the customer when the need to improve a compressed air system arises, usually after the failure of some equipment or when failure is imminent.

Of course when there is a problem with a system the first place a customer will call is their compressed air service provider, so we have set up communication networks with all the compressed air suppliers in Manitoba so we can be quickly made aware of any improvement opportunities. Often to properly size future equipment and to set a base case for incentive calculation purposes a system assessment needs to be done, if this is the case the customer has the option of using the compressed air suppliers or have Manitoba Hydro do the assessment. We then directly pay the service providers to do data logging of the plant and perform basic data collection and end use assessment so the service is at no cost to the customer. When we receive this data from the air compressor service provider, we then have a very good baseline for the system and a foundation on which to make a savings prediction and an incentive offer if future efficiency measures are implemented.

This system works very well and captures a high percentage of all compressed air equipment replacements in Manitoba because all the suppliers are on board with the program. Most suppliers cover territory not covered by Manitoba Hydro and report the take-up of energy efficiency measures in those areas without incentives or assistance is strikingly different.

 

What are the financial incentives offered?

A basic assessment is done at no cost to the customer. If a customer wants a full feasibility study done, we cover 50% of the first $10,000 of the cost of the study, plus 25% of the remaining cost, up to a maximum of $15,000 per study.

Project incentives are paid at 10 cents/kWh for first-year savings - plus $200 per kW on winter-demand and $200 per kW on summer-demand.

There are limits. We don’t pay more than 50% of the total project cost. We don’t pay on projects with less than a one year simple payback. We feel one year payback projects are “no-brainers” and don’t need incentives. Our incentive limits are $250,000 per project, although we will fund higher levels for large special projects.

 

How is measurement and verification of energy savings done?

Measurement and verification (M&V) is currently done on 100% of our projects. We have our suppliers return to the facility when the project is complete and do the logging again to verify results. This is very important because often a simply screw-driver adjustment or incorrect push of a button can change the system control characteristics and cause the system to operate less efficiently. Unfortunately, some suppliers and equipment operators don’t care so much about the system efficiency after the sale and installation justification, so it often becomes our responsibility to make sure the system is working from an energy standpoint and the operators are trained on how the system should be set up.

For M&V we use ACR data loggers (an amp logger) and calibrate them to equivalent power to compensate for power factor changes at different loading levels. We also use a power meters, but amp logging is the safest and most convenient method because you don’t usually have to shut down the compressors for safe installation because no live voltage connection required. Many systems cannot be shut down during normal working hours so it saves us our nights and weekends.

 

What have the results been for compressed air system assessments?

It’s been excellent. In 2009, our group did 97 Performance Optimization projects on all processes including compressed air, blowers, pumps, refrigeration, energy management (demand control), and fans. Compressed air optimization projects represented 86 of the 97 projects done in 2009 – that’s 89% of the total projects! Compressed air projects also received 89% of the total 2009 incentive payout of $2.5 million dollars.

We are pleased to see the growth of all performance optimization projects supported by Manitoba Hydro. We did 45 projects in 2006, 65 projects in 2007, 85 in 2008, and 97 projects in 2009. We are on track to continue to grow the project number in 2010.

 

Any advice for other incentive program managers looking to do more compressed air projects?

My advice is to be “Johnny on the Spot.” and “Keep it Simple” You have to be there in the minds of the customer with an efficient solution to their issues when the inevitable problems happens. In Manitoba, most plant engineers and compressed air suppliers know that when their air system crashes, Hydro is there to assist with substantial funding! For the system to work best good communication with the suppliers and customers through marketing and training is critical.

The incentive program needs to be simple enough for customers to understand and apply to without taking an inordinate amount of the customer’s time. We’ve found the most effective way to increase participation is to cut through most of the red tape on behalf of the customer. In most cases all they have to do is ask for equipment quotations and sign the application papers. We currently do the most of the study and assist the customer in understanding what equipment they need and how it should operate; even following through as long as it takes to ensure the system ultimately works correctly.

 

Where are the main compressed air optimization opportunities?

For very large compressed air systems, the main opportunity is usually reducing compressed air leaks and eliminating inappropriate end uses. For small single-compressor systems, the primary opportunity is most often changing the compressor control mode. Matching the control mode (modulation, load/unload, variable speed drive) with the demand environment will then unlock extra savings potential gained from leak and end use reduction. For example if you reduce leaks and decrease your system demand by 10% and have a modulating compressor, the resulting turn-down of power consumption will only be about 3%.. But if the system is converted to VSD or a start-stop control, a 10% reduction in flow will provide a near linear 10% reduction in energy, thereby unlocking an extra 7% in extra savings.

Reducing the pressure differential in dryers, filters, piping and distribution components also makes a big difference. We often see undersized piping and big pressure drops across filters, connectors, and hoses causing the customer to jack up the main compressor pressure to compensate. A good experiment I like to peform to illustrate the concept with plant personnel is to make a “piping T” with an installed pressure gauge and quick connectors and connect this various air tools. When the tool is not operating there is no pressure drop across it’s associated supply piping because there is no flow, so the gauge reads line pressure. Pull the trigger on the tool and then see what happens, quite often the customer is surprised to see a 30 to 40 psi pressure drop!

We also commonly make the following recommendations:

  • Use bigger compressed air filters. We recommend low-pressure drop mist eliminator filters and/or double-sized filters. This reduces pressure drop significantly and reduces problems like excessive cycling of load/unload air compressors. Install no-loss drains on the filters.
  • Use efficient air dryers with lower pressure differentials and cycling or dewpoint dependent controls.
  • Large control storage (air receivers) should always be installed for better control of all types of compressors, even VSD style, with the bulk of the volume located after the air treatment products for “dry storage”.
  • Regulate the plant pressure using flow control valves at the main compressor rooms.
  • Keep the piping velocity under 30 feet per second in worst case conditions, never blindly size the piping at the same size as the compressor or dryer outlet. This usually means larger pipes but significantly less pressure differential.
  • Recover your compressor heat, this displaces heating loads in winter.

 

What advice do you have for Energy Managers?

Learn more about your compressed air systems by taking courses from the Compressed Air Challenge®. The CAC seminars are excellent and will help you understand the cost of compressed air and what you can do about it. Once you understand the issues, then call in an expert to make a system assessment.

We find the most important compressed air system adjustment is often “between the ears” of the system operator; in making them aware of the high cost and level of waste. System operators and end users need to be aware of the financial implications of compressed air energy issues, so once you are done your training, pass that knowledge on to your people. The Compressed Air Challenge® courses are product neutral so as not to favour any one manufacturer, and are now very accessible due to the development of the CAC’s new web-based training – allowing you to learn at your desk even while you munch your sandwich!

Manitoba Hydro hosts very well attended face-to-face Compressed Air Challenge® training sessions once a year, a key component to the marketing and awareness success of the program.

 

What advice do you have for the equipment manufacturers of compressed air products?

In general, I applaud the recent advancements the air compressor and air treatment manufacturers have made in increasing the efficiency of their equipment. I also commend the Compressed Air & Gas Institute’s (CAGI) efforts in making equipment data sheets available and implementing of the performance verification program. These efforts will continue to help drive up the efficiency of the products and ensure end users can make more efficient choices.

All manufacturers should make sure that their distributors are aware of all the opportunities to save energy in compressed air systems. I know Kaeser Compressors, for example, does some in-house Compressed Air Challenge® training for their own people, I think this training changes the mindset of sales professionals and promotes the offering of better, more efficient projects for their customers.

Some things I’d like to see improve involve integrated air dryers housed within compressor enclosures. We are seeing non-cycling air dryers incorporated into expensive energy-efficient VSD air compressors, in some cases, in the case of lightly loaded systems with low operating hours the dryer can consume more energy than the compressor! I’d like to see the introduction of more efficient cycling, thermal mass or VSD style dryers into these packages.

I’d also like to see air compressor manufacturers stop loading their compressor motors into the service factor. For some time now most manufacturers have been pushing the motor capacity limits to get full load flow cfm numbers up for sales reasons. For example, a typical100 hp compressor motor might consume over 88 kW when the unit is fully loaded at rated pressure, the equivalent to 118 HP. This uses more energy, negatively affects the life of the motors and when ambient temperatures go up – bad things can happen.

 

Thank you for your insights.

 

For more information visit the Compressed Air Challenge® website or contact Ron Marshall, Marshall Compressed Air Consulting, tel: 204-806-2085, email: ronm@mts.net.