Learn before you buy
Better decisions begin with the basics.
18 independent guides to energy, power, compatibility and equipment selection.
Water & Resilience
Getting started
Buying guides
Technical guides
Backup power
Batteries
Solar
Inverters
Generators
EV charging
Electrical basics
Marine
Industrial
All guides
How to size a backup battery
Battery capacity starts with an energy budget. A large Ah number is not enough to tell you what will run, for how long, or whether the battery can start the load.
How to choose an inverter
An inverter has to satisfy the appliance, battery and installation at the same time. Continuous watts are only the first screening criterion.
LiFePO4 versus lead-acid
Compare the energy you can repeatedly use, charging constraints and system changes—not just two Ah labels.
12 V, 24 V or 48 V?
System voltage changes current, cabling and compatibility. Choose it before buying the inverter and battery bank.
How many kWh do I need?
Power tells you what can run together; energy tells you how long it can run. Keep both columns in your planning sheet.
Solar panel sizing
Size solar from daily energy and location-specific seasonal yield. Panel wattage is a test rating, not a daily energy forecast.
MPPT versus PWM controllers
The controller connects two different operating ranges: the PV array and the battery. Select the interface, not just the acronym.
Understanding inverter surge power
A compressor can fail to start even when average power is well below the inverter rating. The complete DC-to-AC path must support the event.
Calculate battery runtime
Runtime is an estimate based on usable energy and real load. Explain the assumptions before treating the result as a purchasing requirement.
Plan an apartment backup system
A practical planning guide: define the job, work through the energy and compatibility constraints, then prepare a supplier brief.
Plan a home backup system
A practical planning guide: define the job, work through the energy and compatibility constraints, then prepare a supplier brief.
RV solar basics
A practical planning guide: define the job, work through the energy and compatibility constraints, then prepare a supplier brief.
Marine battery system planning
A practical planning guide: define the job, work through the energy and compatibility constraints, then prepare a supplier brief.
How to choose a DC-DC charger
A practical planning guide: define the job, work through the energy and compatibility constraints, then prepare a supplier brief.
Generator or battery backup?
A practical planning guide: define the job, work through the energy and compatibility constraints, then prepare a supplier brief.
Home EV charging basics
A practical planning guide: define the job, work through the energy and compatibility constraints, then prepare a supplier brief.
Cable and protection basics
A practical planning guide: define the job, work through the energy and compatibility constraints, then prepare a supplier brief.
Industrial motor and VFD planning
A practical planning guide: define the job, work through the energy and compatibility constraints, then prepare a supplier brief.
Choosing a water system
Start with the source and the job, then verify the exact model. This guide is a selection checklist, not a declaration that your water is safe to drink.