Bills & Rates
Time-of-Use Electricity Rates: When Timing Changes Your Costs
Time-of-use electricity rates charge a different price per kilowatt-hour depending on when you use power, usually more during peak hours and less off-peak. They can…
Explore. Understand. Put it into practice.
The home energy library
Clear explanations, useful examples, and practical next steps. Find a guide for the energy question on your mind.
28 results
A little knowledge for your next decision
Appliance Costs
How Much Electricity Does a Refrigerator Use?
A refrigerator typically draws roughly 300–800 watts while its compressor is running, but it does not run continuously. Its daily energy use is often much…
Solar & Storage
How to Compare Solar Quotes Using the Same Assumptions
To compare solar quotes fairly, recalculate every proposal with the same household consumption, production-modeling method, self-consumption share, import and export rates, incentive treatment, financing basis,…
Bills & Rates
How to Calculate Your Effective Electricity Rate from a Bill
To calculate your effective electricity rate, divide the current billing period's total electric charges by the kWh used in that same period: effective rate =…
Appliance Costs
How to Use a Plug-In Energy Meter to Measure Appliance Costs
Plug the meter into a grounded 120 V outlet, plug the appliance into the meter, and let it log a representative period. Read the kilowatt-hours…
Appliance Costs
How Much Does a Space Heater Cost to Run?
A 1,500-watt space heater running at full power costs about 25.5 cents an hour at 17 cents per kWh—roughly $2.04 for an 8-hour day and…
Energy Explained
Standby Power Explained: Which Devices Still Use Electricity?
Standby power is electricity a device uses when it is switched off or not doing its main job. Many devices with electronics still draw it—clocks,…
Appliance Costs
Why an Appliance’s Rated Watts Do Not Equal Its Daily Energy Use
An appliance’s rated watts describe its power draw under specified conditions; daily energy use is that draw multiplied by actual operating time, converted to kilowatt-hours.…
Energy Explained
kW vs kWh: What the Numbers on Your Electricity Bill Mean
A kilowatt (kW) measures power—how fast electricity is used at a moment—while a kilowatt-hour (kWh) measures energy—the amount used over time. Residential bills usually charge…
Bills & Rates
How Billing Days Can Distort a Month-to-Month Energy Comparison
A bill labeled monthly can cover a different number of days than the previous bill or the calendar month, so total kWh can rise or…