09/15/2010

The Walkthrough Survey for an Energy Audit

Use a walkthrough as an early step in an energy audit

By Eric Woodroof, Ph.D., CEM, CRM

 

Last week I toured a 6 million square-foot facility that had a $21 million annual energy bill. Nevertheless, this facility had no dedicated full-time energy manager.

Does this surprise you?

I have seen many facilities that are willing to spend millions of dollars on energy, with little or no oversight or management. Many facility managers perceive energy as a necessary evil and believe there is little to be done about it.

This is amazing when you consider that with some basic oversight, a 10% savings is highly probable for many facilities, especially if there has been no energy management practice within the last 5 years. A 10% savings on $21 million is $2.1 million, which should be enough to fund an energy department and even some capital improvements … every year.

So the potential for savings can be enormous, not only in reducing consumption but also shifting load to off-peak hours. Many facilities have a "ratchet clause," which means that they pay all year for their high demand during a few peak hours. I have discussed energy issues with people from thousands of facilities, and many have reported that demand charges are 20% to 30% of their total electric bill … sometimes higher! (See table.)  

 


The Cost of Demand Charges
Actual Bill


 


ENERGY


DEMAND


kWh

MMBtu

kWh Cost

kW

Cost

 




($)


($)

 

Dec-08

1,020,600

3,482

22,690

2,678

18,777

 

Jan-09

970,200

3,310

21,082

2,678

18,748

 

Feb-09

1,050,000

3,583

22,220

2,678

18,909

 

Mar-09

1,031,800

3,521

21,122

2,678

18,825

 

Apr-09

1,096,200

3,740

23,721

2,678

18,893

 

May-09

1,311,800

4,476

29,314

2,678

19,199

 

Jun-09

1,369,200

4,672

31,069

2,678

19,281

 

Jul-09

1,482,600

5,059

34,166

2,678

19,458

 

Aug-09

1,449,000

4,944

34,542

2,646

19,066

 

Sep-09

1,229,200

4,194

28,936

2,601

18,733

 

Oct-09

1,367,800

4,667

34,893

2,410

17,602

 

Nov-09

1,157,800

3,950

26,954

2,410

17,482

 

 

14,536,200

49,598

$330,709

 

$224,973

 

 

Good energy practice calls for continual monitoring. A walkthrough survey is a key component of monitoring.

Begin by Collecting Data before the Walkthrough
If you are lucky and can get bill data for similar facilities, you can benchmark your facility against peers and see how they compare. For office or school buildings, it can be easy to get good data. For other building types, such as manufacturing facilities, it may be very is difficult or impossible to get bill data for a facility with similar processes, operation hours, and location.

Other pieces of information to collect before the walkthrough are a list of primary energy-consuming equipment and a plant layout on an 8 1/2 x 11 sheet of paper. Sometimes a fire escape plan can provide the layout and allow you to take notes on it. During the walk-through, I usually note the operation hours of each area (office, shipping, café, etc.) and where the large pieces of equipment are located.

On the day of the walkthrough, I usually spend 1 to 2 hours meeting with the plant manager. I try to discover the facility's material and personnel flows so that I don't recommend something that is infeasible or out of alignment with the long-term plans. It is also critical to understand the hurdle rate, minimum acceptable rate of return, or financial criteria that the facility manager expects for energy projects. This information helps you eliminate projects that are beyond the payback period.

Then I walk the site until lunchtime. At lunch, the survey team will formulate a list of opportunities, confirm the opportunity list with the facility manager, and then spend the rest of the day quantifying the opportunities and collecting measurements.

Understanding maintenance is key to long-term energy success. If the maintenance team doesn't understand a system, energy will be lost. An analogy is the microwave oven in my kitchen. It can do all sorts of cool functions, but I have no idea how to do those and I get by with the basics: open the door, input the time and push start. If a maintenance team is getting by without training on things like economizer controls, waste heat recovery, etc., opportunities for improvement exist. Also, if a facility does not have a maintenance policy about compressed air leaks, motors, chillers, etc., that lack of policy usually creates a lot of opportunities … and 5% to 15% savings!

Finally, safety is important if you want to survive to the next walkthrough. Safety glasses, ear protection, and hard hats in construction areas are good things to have in your toolbox. Don't touch electrical systems (high voltage buses, etc.), be aware of potentially very hot surfaces in the mechanical room, and never wear a necktie, especially around motors. If a facility staff does not supply you with adequate safety gear, it probably won't make energy management a priority either.

In next month's newsletter I will talk about advanced auditing techniques and data collection.

 

Eric Woodroof, Ph.D., is the Chairman of the Board for the Certified Carbon Reduction Manager (CRM) program and a board member since 1999 of the Certified Energy Manager (CEM) Program. He is a strategic advisor, corporate trainer, keynote speaker, and founder of ProfitableGreenSolutions.com.


 


 


Visit our website today to learn about the design flexibility of a Morton building and the endless possibilities of partnering with our designBUILD team.


Wood construction is both cost and energy efficient. Check out Morton Buildings and our designBUILD team online today to discover all the benefits of post-frame construction.


When choosing a metal-clad building for your next construction project, consider Morton Buildings, Inc., and their designBUILD team, we’ll make your dream a reality.

We Can Help You Reduce Energy by 30%

Our mission is to help our customers manage their buildings' energy costs, improve reliability, and enhance performance while having a positive impact on the environment.
CLICK HERE to find out how.

Bluebeam® Revu® simplifies digital facilities document management from design review to leveraging as-builts, maintenance manuals and O&Ms submittals.

 


Visit our website today to learn about the design flexibility of a Morton building and the endless possibilities of partnering with our designBUILD team.


Wood construction is both cost and energy efficient. Check out Morton Buildings and our designBUILD team online today to discover all the benefits of post-frame construction.


When choosing a metal-clad building for your next construction project, consider Morton Buildings, Inc., and their designBUILD team, we’ll make your dream a reality.

We Can Help You Reduce Energy by 30%

Our mission is to help our customers manage their buildings' energy costs, improve reliability, and enhance performance while having a positive impact on the environment.
CLICK HERE to find out how.

Bluebeam® Revu® simplifies digital facilities document management from design review to leveraging as-builts, maintenance manuals and O&Ms submittals.

 


 
comments powered by Disqus

Related Products

Sponsored Links