Home energy guides
Transparent formulas, practical examples and limitations.
How to read an electricity bill
Charges, periods and readings without guesswork.
GuideEnergy supply vs distribution
Why a bill contains several different types of charges.
GuideFixed and variable energy charges
What saving one kWh changes and what it does not.
GuideHow to calculate the real kWh cost
All-in rate, marginal rate and when to use each.
GuideHow to track meter readings
Dates, corrections, replacements and data consistency.
GuideMonthly energy analysis
How to compare periods of different lengths.
GuideHow to detect increased energy use
Trend, seasonality and unusual events.
GuideHow to use a plug-in energy meter
Measure cycles, standby and variable operation.
GuideHow to calculate appliance cost
Power, time, cycle and actual measurement.
GuideStandby energy cost
A small continuous load can matter over a year.
GuideHow to import energy CSV data
Columns, units, time zone and gaps.
GuideHow to analyze a daily load profile
Base load, peaks and overnight usage.
GuideHow to compare electricity tariffs
Your load profile matters more than a tariff name.
GuideSingle rate vs time-of-use tariff
When shifting usage changes the result.
GuideDynamic electricity tariffs
Hourly prices, risk and automation.
GuideHow to shift energy use to cheaper hours
Appliance constraints and household comfort.
GuideHow to calculate electric heating cost
Useful heat and unit energy rate.
GuideHow to calculate gas heating cost
Efficiency, billed kWh and fixed charges.
GuideHow to compare heating systems
The same useful heat requirement across fuels.
GuideWhat heating efficiency means
Limits of a simple model and seasonal data.
GuideWhat heat pump COP means
A single operating point is not a seasonal result.
GuideWhat SCOP means
How to use the metric without false precision.
GuideHow to estimate heat pump cost
Heat demand, SCOP, backup heater and tariff.
GuideHow to calculate hot water energy
Temperature, volume and storage losses.
GuideHow to analyze home solar
Production is not the same as savings.
GuideSolar self-consumption
Definition, measurement and ways to improve it.
GuideEnergy self-sufficiency
A different metric from self-consumption.
GuideHow to read inverter data
Production, import, export and missing channels.
GuideHow to analyze solar export
Export value depends on the actual settlement method.
GuideHome battery basics
Capacity, power, reserve and efficiency.
GuideBattery round-trip efficiency
Why you do not recover all stored energy.
GuideHome EV charging
Wall energy, losses and tariff.
GuideEV cost per 100 km
Vehicle consumption and charging efficiency.
GuideHow to plan an energy upgrade
Cost, scope, dependencies and sequence.
GuideSimple payback period
A simple metric with important limitations.
GuideNPV for energy upgrades in plain language
Time value of money and analysis period.
GuideHow to compare energy scenarios
Consistent assumptions and sensitivity analysis.
GuideHow to prepare a home energy report
Scope, sources, period and limitations.
GuideHow to protect energy bill data
Local processing, minimization and safe exports.
GuideHow to back up an energy project
ZIP, encryption and restoration testing.
GuideCommon energy calculation mistakes
Units, periods, efficiency and double counting.
GuideThe difference between kW and kWh
Power and energy are different quantities.
GuideConverting GJ, MJ and kWh
Correct conversion factors and billing context.
GuideHow to document a change in energy use
Before-and-after comparison without oversimplified conclusions.