Most people can probably remember the days when McDonald’s products came packaged in polystyrene. As public awareness of polystyrene’s damage on the environment grew, so did the pressure for McDonald’s to stop using the material more commonly known as Styrofoam. McDonald’s finally realized that the public, and the planet, deserved a more environmentally friendly packaging material for their food products and discontinued the use of polystyrene. That was several years ago, and now McDonald’s has taken a new initiative in making their environmental impact an example for others to follow as they proudly unveiled “The Energy-Friendly McDonald’s.”

The project began with an agreement. In late 1996, Michigan’s largest power company Detroit Edison announced a long-term power supply contract with McDonald’s Corp. and its 63 franchisees in southeastern Michigan.

Under the contract, Detroit Edison agreed to provide power to the more than 200 McDonald’s restaurants served by the utility, including those operated by the franchisees.

One of the more important points of the contract called for Detroit Edison to assist McDonald’s in the design and development of an energy-efficient prototype restaurant. The utility offered their expertise in energy efficiency and suggested energy-efficient products and techniques that were available for commercial applications at a reasonable cost. Plus, a Detroit Edison Energy Engineer oversaw all energy-efficiency items that were used and installed.

Detroit Edison will also perform energy audits on McDonald’s existing restaurants to evaluate indoor and outdoor lighting, cooking equipment, refrigeration and energy-use patterns. In return for its 10-year commitment, McDonald’s will receive an immediate reduction in the price it pays for electricity, along with price certainty during the contract period.

Though the contract does not represent the first of its kind, it is the first in the United States with a major fast-service restaurant chain.

Deemed a “win-win” situation by both McDonald’s and Detroit Edison, construction on the Energy-Friendly McDonald’s began in October 1997 and was officially opened for business on December 30th of the same year. The restaurant, located in Westland, MI, just outside of Detroit, is the fifth such McDonald’s in existence in the United States. The restaurant itself is approximately 3,600 square feet in size with a 1,500-square-foot kitchen/dining area, in addition to a 1,200-square-foot, two-story Ronald’s PlayPlace. It has seating for 65 people.

Both Detroit Edison and McDonald’s will be comparing the costs of operations with an identical McDonald’s restaurant a few miles away in Northville, MI. The contrasting restaurant is similar is shape, size, configuration, and is even facing the same direction as the Westland location. The plan is to evaluate the equipment’s “moderately more expensive” initial costs versus the long term cost, profitability, and bottom-line savings.

Members of the construction team consisted of companies throughout the midwest including, Water Furnace in Fort Wayne, IN; SHG, Inc. in Detroit; Wisner Electric in Lansing, MI; and Groesbeck Glazing in Warren, MI.

The Earth’s Efficiency

The heart of the energy efficiency is the Geothermal Heating and Cooling System. Billed as the world’s most efficient heating and cooling system, the closed-loop vertical system utilizes the earth’s natural temperatures to heat and cool the building more efficiently. Also known as a Geoexchange, ground source, ground water, or earth-coupled heat pump, a geothermal system taps into the constant temperature of the earth to provide year-round heating and cooling at significantly lower costs than traditional technologies. Other benefits include enhanced comfort and control, space savings and the virtual elimination of dependence on fossil fuels. Studies have shown that a geothermal heating and cooling system uses 20% less energy and produces 50% less greenhouse gases than a conventional natural gas rooftop system.

The installation of a geothermal heating-and-cooling system basically requires three components: a heat exchanger for collecting the heat, a compressor to enhance the heat, and a fan to distribute the heated air through a standard ductwork system. The heat exchanger most often consists of a continuous loop of polyethylene pipe, buried in the ground, filled with an environmentally safe water/antifreeze solution, joined to the compressor (the indoor unit), and sealed. The pipe is made of the same material used for gas lines. Pipe joints are heat-welded, and the loop, which is totally inert in the ground, is pressure-tested. The ground heater exchanger and its associated piping is renowned for its ease of maintenance and features a life expectancy of at least 50 years.

In the case of this McDonald’s, three, 11-ton rooftop heat pump units are connected to the ground loop heat exchanger. The heat exchanger comprises 32 boreholes drilled 195 feet below ground. The system of piping connects to the three heat pumps on the roof.

The natural heat of the earth is absorbed by the solution in the loop system. The temperature of the earth remains relatively steady at 50°F. Of course, 50°F is not enough heat to properly warm a restaurant during Michigan’s winter months so increasing the temperature of the earth’s heat involves a cycle of evaporation, compression, condensation, and expansion.

As the water/antifreeze solution from the ground loops is pumped by the indoor unit, it flows over and around a smaller loop system, which is filled with refrigerant. The refrigerant is in a smaller, interior tube. The ground water flows through a larger, outer tube.

In gaseous form, the refrigerant travels through its loop to the compressor, where it is pressurized to a temperature exceeding 180 degrees, then the refrigerant is conveyed through the outlet tube to the radiator. A fan pulls air across the radiator coils where the air absorbs heat emitted by the pressurized gas. The heated air is then distributed via the restaurant’s ductwork system. With the heat extracted, the refrigerant returns to liquid form, and the cycle begins anew.

When the weather becomes warmer, cooling is effected by simply reversing the cycle. In the heating phase, the earth’s heat is brought into the restaurant. In the cooling phase, the heat is taken out of the restaurant and returned to the cooler earth.

Overall the system emits 20-30% less greenhouse gas than conventional fossil-based systems. Factory-sealed refrigeration systems don’t harm the ozone layer. Commercial applications typically reduce energy consumption by 25-35% and when installed as a retrofit, the system typically pays for itself in 5-10 years.

Shedding Light

The lighting needs of the McDonald’s were also carefully examined in order to select the most energy-efficient yet cost-effective means for illumination. Even though lighting requirements ranged from the parking lots to the bathrooms, each light fixture is state-of-the art and is expected to provide savings as much as 65 to 80 watts per fixture.

Kitchen and dining room areas use low-watt electronic fluorescent light ballasts while the Ronald’s PlayPlace and parking lot use low-watt metal halide lamps. Ultrasonic sensors are used to dim lights when rooms are unoccupied. Photoelectric sensors are used to dim other lights when natural sunlight is sufficient.

Low-watt Electronic Ballasts

The solid state electronics in these fluorescent lamps energize the low-pressure mercury vapor and inert gases within, elevating them to a higher level. As the gases revert to their naturally lower energy levels, they emit ultraviolet photons that react with the light’s phosphor-lined surface and emit visible photons or light. Electronic ballasts are 12.5% more energy efficient than older magnetic ballasts.

Low-watt Metal Halide Lamps

Low-watt metal halide lamps feature an oblong arc tube instead of the straight tube found in traditional metal halide lamps. This “football” shape allows an optimum temperature to form around the arc which reacts with the halide gas in the lamp and remits energy in the form of light. Uniform heating of the lamp gases produces more light with the same amount of energy. Low-watt metal halide lamps are about 20% more energy efficient and last 7% longer than regular metal halide lamps.

Ultrasonic & Photoelectric Sensors

Designers took great care to install sensitive lighting systems that could react to the environment. Automatic sensors connected to dimming ballasts in the fluorescent lights in the restaurant shut off lights when not needed. Ultrasonic sensors automatically activate bathroom lights when someone enters. The same sensors dim the bathroom lights when the room becomes unoccupied. Photoelectric sensors near the windows automatically dim the lights when a sufficient amount of natural sunlight is present. The advantages to such a system are obvious; the lights are only activated when needed. This feature helps to cut back on energy use, improves energy efficiency, extends bulb life, and eliminates the “human factor.”

Heat Mirror Insulated Glass

Designers utilized “sunglasses” for the windows to increase energy efficiency. The triple-unit glass used in the restaurant consists of a heat reflective coated film suspended inside a two-pocket insulating glass unit. The film reflects solar radiation, and the double air space reduces the conductive heat transfer, thereby minimizing heat transfer and maximizing cooling system efficiency. The savings this system offers is pronounced with 50% more efficiency in reducing thermal solar radiation and 36% more efficiency in reducing thermal conduction and convection.

High-efficiency Gas Water Heater

A high-efficiency burner and an expanded heat exchanger remove excess heat from flue gasses prior to venting. The hot gases are channeled through 37 feet of a specially designed helical heat exchanger, which transfers much of the flue gas heat to the stored water. The heater optimizes combustion efficiency and features extra insulation to minimize heat loss. The high-efficiency natural gas water heater is 20% more energy efficient when compared with regular water heaters.

High-efficiency Electric Motors

As typical electric motors convert electric energy to mechanical energy, the transformation loses energy through four mechanisms – ohmic heating, core losses, friction losses, and stray losses. Attempts to curb the losses at any of the mechanisms often increase the loss in another, and motor design modifications can result in unrealistic price increases. High-efficiency electric motors are carefully designed to balance motor mechanism energy loss at a cost-efficient price. These powerfully efficient electric motors are 5% more energy efficient versus ordinary electric motors.

What’s Next

While the total energy savings during actual restaurant operations has yet to be determined, both McDonald’s and Detroit Edison officials are confident the restaurant will prove itself as a plausible alternative to traditional construction techniques. Ultimately, further construction of more energy-friendly McDonalds’ will rest partly on the ability of the Westland restaurant to produce a bottom-line operational savings. One thing is certain, however, the McDonald’s and Detroit Edison partnership is one from which, once again, both the public and the planet should surely benefit.