It’s easy to get kilowatt-hours (kWh) and kilowatts (kW) mixed up when talking about energy consumption. The main difference between kilowatts and kilowatt-hours is in what they measure.
What is Demand? from SE on Vimeo.
Understanding Your Energy Use
What is a Kilowatt-Hour (kWh)?
A kilowatt-hour (kWh) measures the amount of energy your home or business uses over time. For example:
- Running a 1,000-watt vacuum cleaner for 1 hour uses 1 kWh.
- Watching a 100-watt LED TV for 10 hours uses 1 kWh.
- Using a 2,000-watt clothes dryer for 30 minutes uses 1 kWh.
The front of your billing statement shows your energy use in kWh for the current month, the previous month, and the same month last year. To reduce your electric bill, use devices that consume fewer watts or limit their usage time.
What is a Kilowatt (kW)?
A kilowatt (kW) measures power, indicating the volume of electricity your home or business uses at a specific point in time. 1 kilowatt equals 1,000 watts. Because watts are small, kilowatts are used for measuring whole-house electricity use.
What is Demand?
Demand, measured in kW, represents the rate at which electricity is consumed at any given moment during a billing period. At Salem Electric, the peak demand is averaged over a 15-minute interval and displayed on your billing statement, even if your rate class doesn’t charge for demand.
Reducing demand helps keep rates low for everyone. During busy times or extreme weather, the power grid can be strained. Simple actions like using timers to run appliances at night help ensure energy availability when it’s needed most.
How Does Demand Affect My Energy Bill?
If your rate class includes a demand charge, it can significantly impact your bill.
- High electricity use over a short period increases your demand charge.
- Consistent electricity use keeps the demand charge smaller.
Example:
- Company A: An auto repair shop open 30 hours a week uses 40 kW over 120 hours per month. They require 100 kW for one hour monthly to start their machines. This results in 4,800 kWh of energy use and a peak demand of 100 kW. In addition to their energy charges for the 4,800 kWh, they will also pay demand charges for the 100 kW.
- Company B: A printing business open 40 hours a week uses 20 kW over 160 hours per month. Their energy use is 3,200 kWh with a peak demand of 20 kW. In addition to the energy charges for the 3,200 kWh, Company B will also pay demand charges for the 20 kW.
Tips for Managing Demand
By understanding and managing your energy use, you can make informed decisions that help reduce your electric bill and contribute to a more efficient power grid.
- Check Salem Electric’s Rate Schedule (PDF) to identify your rate class and monthly demand charge
- Track and manage your energy use through SmartHub where you can set up custom alerts to notify you if your energy consumption exceeds normal usage
- Commercial members:
- Evaluate your operations to reduce demand
- Shift energy use to less busy times
- Stagger the use of heavy equipment
- Use equipment at lower intensities
- Install energy-efficient equipment to help lower demand
- Contact Salem Electric for information on Incentives