TOPIC COLLECTION
Independent energy
A focused path through related explanations and calculation tools.
LEARN THE SYSTEM
Guides in this topic
Build a power plan that survives a cloudy week.
Separate energy, peak power and autonomy before sizing solar, batteries and backup.
Choose backup power around the loads that must run.
Understand running power, motor starts, safe placement and the connection to the house.
Plan domestic hot water as an energy system
Estimate heating energy, then account for peak demand, recovery, storage and safety.
Plan how an off-grid battery gets recharged
Connect usable deficit, charger power, source limits, losses and recovery time.
Plan off-grid energy through several low-sun days
Build a period energy balance, preserve battery reserve and define when backup generation starts.
Plan useful hot-water storage for a household
Translate tank litres into delivered hot water by checking temperatures, peak draws, recovery time and energy availability.
USE THE NUMBERS
Calculators in this topic
Generator running & starting load
Check one documented motor start against other running loads.
Daily electricity budget
Add three appliance groups using power and actual daily running time.
Solar array energy balance
Estimate DC array size from daily energy and a monthly solar assumption.
Battery autonomy
Convert a daily load into nominal battery capacity with stated losses.
Energy to heat water
Estimate heat and input energy for a known water volume and temperature rise.
Shower water, energy and running cost
Estimate water use, water-heating energy and combined operating cost for a household shower pattern.
Battery recharge time
Estimate ideal recharge time between two states of charge.
Generator fuel runtime
Convert usable stored fuel and measured consumption into a simple operating-time estimate.
Solar energy balance over a low-sun period
Compare estimated solar production with critical-load demand over several days.
Generator-assisted battery recharge plan
Estimate recharge time, generator-side demand and fuel for a stated battery deficit.
Battery autonomy after load shedding
Compare battery runtime before and after reducing the daily critical-load budget.
Pump electricity use and operating cost
Estimate electricity and cost from measured input power, daily run time and a chosen period.
Hot-water recirculation energy and cost
Estimate annual pump electricity and the energy needed to replace heat lost from a hot recirculation loop.
Hot-water tank recovery time
Estimate the energy, cost and ideal time needed to heat a stored volume between two temperatures.
Usable hot-water storage
Estimate the mixed-water volume, shower time and stored heat available from a hot-water tank.