Buying guides

Choose a guide, check the worked example and continue to a calculator or equipment category.

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.

MPPT versus PWM controllers

The controller connects two different operating ranges: the PV array and the battery. Select the interface, not just the acronym.

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.

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