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Reference material on how off-grid systems actually work: what the specifications mean, what the trade-offs are, and where the expensive mistakes hide.
Batteries
How to Size an Off-Grid Battery Bank
A step-by-step method for sizing an off-grid battery bank, including days of autonomy, depth of discharge, inverter losses, and the cold-weather derate people forget.
Lithium vs AGM: Where Each One Still Wins
A direct comparison of lithium, AGM and flooded lead-acid for off-grid use, on usable capacity, cycle life, real cost per kilowatt-hour and cold weather behavior, including the two cases where lead-acid is still the right answer.
How off-grid batteries actually work: chemistry differences, usable versus rated capacity, cycle life, and how to compare real cost per kilowatt-hour.
The real hazards of an off-grid battery bank: short-circuit energy, hydrogen venting, thermal runaway, and the overcurrent protection that prevents all three.
Charge Controllers
Types of Solar Charge Controllers: PWM, MPPT and Sizing
What a charge controller does, how MPPT and PWM differ, how to size one correctly, and why panel voltage decides which type is worth buying.
Climate
Off-Grid Solar in Cold and Difficult Climates
How cold, snow, short winter days, and extreme heat affect an off-grid system, and how to size and site one so it works in the month that matters.
Generators & Backup
Generators for Off-Grid Systems
Choosing and sizing a generator for an off-grid system: why it charges the bank rather than running the house, why an inverter/charger can refuse dirty power, and why propane usually beats gasoline off-grid.
Inverters
What an off-grid inverter does, why pure sine wave matters, how to size continuous and surge capacity, and how off-grid, hybrid, and grid-tie inverters differ.
Panels
Working safely with solar panels: why an array is live whenever there is light, DC arc hazards, roof and ground-mount risks, and safe wiring practice.
How to read a solar panel datasheet, what monocrystalline and polycrystalline actually change, why panels never make their rated power, and how wiring them in series or parallel affects the rest of the system.
Solar Basics
How an off-grid solar system works end to end, the vocabulary you need to read the rest of the guide, and the order in which the decisions have to be made.
Solar Generator vs DIY Solar: What the Box Trades Away
A solar generator puts the battery, inverter and charge controller in one case. What that buys you, what it costs you in solar input, expansion and voltage, and which loads each shape of system suits.
Water
Solar Well Pumps: How They Work and How to Size One
How a solar well pump system works, the three things to find out before you buy, and how to size the pump and its solar array.
What Size Generator for a Well Pump: The Start Decides It
How big a generator a well pump needs: why the start sets the size, Franklin Electric's minimum generator for each submersible motor, and how to read a jet pump's code letter.
Wiring & Safety
DC Voltage Ratings: Why a 48V Switch Is Not for a 48V Bank
A 48 volt battery bank is never at 48 volts. Published maximum voltage ratings for common battery switches and fuses, why a part labeled 48V is the wrong part, and how to check a rating against the number that matters.
Fuse Interrupt Rating: 12V Is Not 48V
Interrupt capacity is the fuse specification most off-grid builds get wrong. Published AIC figures for Class T, ANL, AMG and MRBF terminal fuses, and why one of them changes verdict entirely between 12 and 48 volts.
Conductor sizing, voltage drop, overcurrent protection, grounding, and disconnects for off-grid DC systems, following the NEC.