Smart Grid / Energy and Water Terms

Energy and Water Terms

Time-of-Use rates are common in other parts of the U.S., but new to the Mid-South. The concept requires understanding a few terms that also may be new to you.

  • Conservation: An action that results in less energy or water being consumed. Examples of energy conservation include: raising your thermostat for cooling, turning off unnecessary lights and electronics, closing the exterior door when the furnace or air conditioner is operating,and closing the refrigerator door quickly.  Examples of water conservation include: fixing a leaky faucet, toilet or showerhead, setting outdoor sprinklers to not run after (or during) a rain shower, and using a broom instead of the hose to clean off the driveway.
  • Efficiency: A purchase of equipment, appliance or material that uses less energy or water than the unit it replaces. Examples: replacing your old air conditioning system with a newer version, adding attic insulation, replacing standard incandescent lights bulbs with compact fluorescent light bulbs or LEDs, and replacing windows and doors with more energy-efficient ones. Buying an Energy Star refrigerator would also apply, but only if the old refrigerator is discarded. (Moving the old one to the garage or utility room actually consumes more electricity, so consider whether the convenience of two units is worth the higher MLGW bill!)  Examples of water efficiency include installing a low-flow showerhead or EPA Water Sense-labeled toilet, which uses significantly less water.
  • Demand Response, also known as Load Shifting or Peak Shaving: An action that results in changing the time during which electricity is consumed, often without changing the total amount of electricity consumed. Typically involves moving consumption from on-peak periods (when demand and costs are higher) to off-peak periods (when demand and costs are lower). Household examples: running the dishwasher at bedtime instead of immediately after dinner or washing and drying clothes on weekends instead of weekday afternoons. Many local businesses, organizations and schools participate in the TVA/EnerNOC Demand Response program, where they adjust thermostats and lighting systems, change production schedules and make other operational decisions when alerted of the need to lower TVA system peak demand during specific hours on specific days. Find tips to maximize your residential load shifting strategy for Time-of-Use rates
  • Generation Costs: The cost of generating electricity varies on a daily—and even hourly—basis, depending on the fuel source, total electric demand and weather. MLGW's power generator, TVA, actually owns generation plants that operate for only a few hours a year in order to meet peak demand. Peak demand typically occurs on weekday afternoons in the Summer when temperatures are highest, driving air conditioning use in both homes and businesses. (A smaller peak demand occurs on Winter weekday mornings and is attributed to electricity use for heating and water heating across the region.) When TVA generation isn’t enough to meet peak demand, TVA also buys power from other suppliers. Learn more about TVA generation and purchased power here.  MLGW's retail electric rates have always reflected the average cost of TVA power, whereas the Time-of-Use rate option recognizes when power is needed and rewards customers who consume less electricity during expensive on-peak hours and more electricity during off-peak hours.
  • Hundred Cubic Feet (CCF):  Unit of measure for natural gas and water usage.  One CCF of natural gas is equal to roughly one therm, which is another common unit of measure.  One CCF of water is equal to 748 gallons.  Natural gas and water usage on your MLGW bill are shown in CCF.
  • KiloWatt (kW):  Unit of measure for electric demand, also called electric load. 
  • KiloWatt-Hour (kWh):  Unit of measure for electricity usage.  One kWh equals 1,000 watts of electricity consumed over a one-hour period, or 100 watts over a 10 hour period, as well as other combinations.  Your MLGW bill shows kWh in the Usage column for electricity.