A movement that began in the 1950s and has grown more widespread over the years is the mega-church. Mega-churches are large churches that have 2,000 or more worshippers for a typical service. These churches have large structures and parking lots that are able to accommodate the huge numbers of worshipers they attract. Many mega-church facilities are more akin to a theater or arena, with high-tech lighting, sound and video systems. In addition to a sanctuary/worship space, mega-church facilities can contain other space types such as retail, restaurant or office.
Because of their size and/or use of multiple facilities, mega-churches offer unique challenges with regards to energy efficiency when compared to a regular congregational facility. It is still important to use energy-efficient products and equipment whenever possible. However, the proper controlling of those energy-efficient products and equipment is going to be crucial in saving energy.
The two systems that are most important to focus on with regards to controlling are the lighting and HVAC systems. These systems account for a large portion of the energy used in a facility and can be a prime area for energy-efficiency upgrades.
There are lighting controls beyond the basic light switch that give you better flexibility in lighting usage and can save energy. Examples of these controls are occupancy sensors, dimmers, and daylight sensors.
Zones: lights are switched on corresponding to the use and layout of the lit areas, in order to avoid lighting a large area if only a small part of it needs light.
Time control: to switch on and off automatically in each zone to a preset schedule for light use.
Passive Infra-Red (PIR) Occupancy sensing: in areas that are occupied intermittently, occupancy sensors can be used to indicate whether or not anybody is present and switch the light on or off accordingly.
Light level monitoring: this consists of switching or dimming artificial lighting to maintain a light level measured by a photocell.
Bi-level switching: a strategy that allows for better control of individual rooms/spaces. For example, specified areas are provided with two wall switches near the doorway to control the lights. In a typical installation, one switch would control 1/3 of the fluorescent lamps in the ceiling lighting system, while the other switch would control the remaining 2/3 of the lamps. This allows four possible light levels: OFF, 1/3, 2/3 and FULL lighting.
More information is available on these controls under "Lighting Controls" in the "Lighting" section of this Guide.
To improve the efficiency of the heating and cooling systems in your congregational facility there are control strategies that you can incorporate that will run these systems only when necessary. Common control strategies include programmable thermostats, multiple zones, and CO2 demand sensors for ventilation control. More information is available on these control strategies under "Control Systems" in the "HVAC" section of this Guide.
Congregational facilities might consider installing network thermostat systems, not only because of their simplicity and power, but also because they are affordable and allow for the system to expand as budget, time and the size of the facilities grow. With these systems you can control and monitor a single thermostat, or an entire building or multiple-building site using a personal computer.
Computerized management of lights, heating, cooling, and other systems can be worthwhile for larger facilities like mega-churches. Energy management systems are computer-based tools that allow you to monitor, track, analyze, control, and optimize the performance of systems in one facility or for multiple locations and help reduce your energy consumption. This can even be done remotely from a computer that is not onsite. By combining EMS with the proper energy-efficient equipment, your facility can be on the road to saving energy, reducing pollution, and saving financial resources.
Simple identification and measurement techniques can be the first step toward eliminating waste and saving money. For example, you may discover that your peak electricity use occurs during a time of year when rates are at their highest. Using energy mapping tools can help identify issues like these and allow you to take action toward savings.
Mega-churches are large enough that they may be susceptible to high demand charges from their electric utilities. In order to minimize this cost consider Demand Response Controls.
Digital demand controllers (DDCs) are small, relatively inexpensive energy-management devices that can simultaneously control the operation of a large number of equipment items, preventing all or most of them from operating simultaneously. The objective is to avoid the creation of power-demand "spikes" (i.e., short periods when power demand is unusually high), which often leads to high monthly demand charges.
The operation of some electrical loads in a facility (such as internal lighting) cannot be interrupted without causing a disruption. But many others - typically those that have some thermal-energy storage associated with them, such as water heating, air-conditioning, electric space-heating units, or refrigeration equipment - can be interrupted for periods of 10 to 30 minutes without occupants being aware of the interruption. These are the loads selected for peak-demand-limiting controls via a DDC.
DDC units can also be used to reduce electrical demand during periods when the utility grid is challenged and in danger of overloading, or when electricity prices are unusually high. Many utilities offer financial incentives to customers who install DDC units or other equipment that enable the utility to reduce the customer's load at these times.