Energy conservation

Nation's Restaurant News, August 26, 1985

ENERGY CONSERVATION

The kitchen is more than just the hub of activity in a restaurant. It's also the place with the most energy requirements --expensive energy, considering that the cost of energy has gone up from a fraction of a per cent to between 4%-6% of a typical restaurant's annual gross sales. But unlike some other overhead factors --food costs, say--over which the operator can exercise little control, technological advances have made energy usage a prime area for operating cost savings. Best, each dollar saved in energy costs goes directly to the bottom line.

Nation's Restaurant News spoke about energy conservation projects with Robert Doering, Ph.D., P.R., Professor of Engineering in the Department of Industrial Engineering and Management Systems at the University of Central Florida in Orlando. Doering specializes in energy systems at food-service operations and has worked as a consultant for a number of restaurant companies and operators, including Red Lobster and the Epcot Center in Florida.

Q. Dr. Doering, let's start with some basics. What's the best primary source of energy for a restaurant --gas or electricity?

A. Overall, gas is typically more cost effective, in the areas of space heating and hot water generating. Electricity is needed for lighting and motors. Many times, though, natural gas is not available at a specific site, and any energy selection should be made only after considering all projected energy costs, rate structure and operational requirements.

Q. An electric power bill is frequently heavily impacted by the demand charge. What can a restaurateur do to reduce that charge?

A. Demand charge is a basic cost component that reflects maximum connected load, kw or KVA, over any 15- to 30-minute period each month. Because of operational requirements, the peak power demand will vary randomly over those periods as equipment cycles on and off. It's quite probable that at one time in this metered interval, all loads will connect at the same time, and this high peak demand will translate into a high energy bill.

A good way to mitigate this problem is by installing a demand control system, which is available from a number of manufacturers. The system includes a load sensing device that monitors demand and controls it to a set point limit through programmed control of equipment. Demand controllers can be programmed to know which equipment can be shut down and for how long on a priority system to keep the demand below the set point.

Demand controllers are still not used as widely as they should be, though, and that's mostly because until recently they've been too expensive for the typical restaurant to install. But now we're finding that a 300-seat restaurant, for example, can put one in for about $3,000 or $4,000, with a typical two or three year payback. I predict that demand controllers will become more popular in the restaurant industry because of recent relatively large increases in rates.

Keep in mind that it's generally less costly to install a demand controller when you're building your restaurant, not after. But some stores do have a central point of control for their air-conditioning and other support equipment which facilitates a retrofit installation of a demand control system. And the systems are fairly maintenance free, as long as people don't diddle with them.

Q. Controlling temperature loss to the outside and interdicting solar heat gain pose one obvious challenge. What are the options for a restaurateur?

A. First you make sure that you have the proper structural insulation. That should happen when you design the building; otherwise it becomes too difficult to do much about it that is cost effective. If you follow your particular state's energy code, you're pretty sure that you're putting in everything that needs to be done in terms of proper insulation.

As far as preventing solar heat gain, mostly through windows, a good way to do so is by placing something outside building openings--in other words, shading them, for example, with natural vegetation, such as trees. If you can't do that, one of the most effective methods of reducing solar radiation heat gain is with solar film, which you put on the inside of the window glass and which is relatively inexpensive and cost-effective. There are some architectural and marketing considerations to be taken into account with solar film--it produces a one-way mirror effect when it's lighter outside than inside the restaurant-- but on the whole solar film works very well and is relatively low cost.

Q. In an article in The Consultant magazine last year, you talked about "human factor considerations' in comfort conditioning systems. What are those factors in a restaurant/kitchen environment?

A. I'm saying that there are different comfort conditions, depending on what people are doing, how they are dressed and so forth. You'll always have a dichotomy of comfort conditions preferred by the waitresses who are busy serving the tables and the seated customers. Typically, I believe, buildings are kept too cool, because operators want to satisfy their workers first. This makes customers uncomfortable. I think it should be the other way around. First of all, it costs more money to maintain the cooler condition. One solution would be to put in a waitress alley where you could control the distribution of conditioning to satisfy the waitresses and bus boys while the dining area is controlled to please the customers. My basic argument is that the guest is the most important factor in a restaurant, and his comfort should not be compromised.