Field notes
Electricity cost guides
Learn how to create estimates you can audit, update, and compare without confusing an estimate with a utility bill.
How to Calculate Appliance Electricity Cost
A complete, auditable method for converting watts and operating time into daily, monthly, and annual electricity costs.
Read the guide Practical guideHow to Measure Appliance Wattage
Learn when to use a nameplate, EnergyGuide label, plug-in meter, or utility data for a defensible energy estimate.
Read the guide Practical guideUnderstanding Appliance Duty Cycle
Understand why thermostatic and compressor-driven appliances draw rated power only part of the time.
Read the guide Practical guideHow to Read an EnergyGuide Label
Use the yellow EnergyGuide label correctly, including annual kWh, estimated cost assumptions, and comparison ranges.
Read the guide Practical guideHow to Find Your Electricity Rate
Find a useful cents-per-kWh estimate on a bill and understand fixed fees, tiers, taxes, and time-of-use pricing.
Read the guide Practical guideHow to Compare Appliance Energy Use
Compare appliances fairly by normalizing cycle length, frequency, quantity, duty cycle, and electricity price.
Read the guide Practical guidePlanning for Seasonal Appliance Costs
Build summer and winter scenarios without pretending one month represents a full year of appliance use.
Read the guide Practical guideWhy Your Electric Bill Changes
Separate usage, price, weather, billing-period, and fixed-charge effects before blaming one appliance.
Read the guide