THE BACKUP POWER LIBRARY · From THE BUY CHECK

The number on the box is
not the number you get

Capacity is quoted at the battery, not at your outlet. Output is a peak the unit holds for a fraction of a second. Two books that tell you which figures actually decide whether it runs your fridge.

62
Field Notes
121
Pages
13
Diagrams
30-Day
Money Back
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Most people size against the wrong number

They buy by the biggest figure on the listing, then find the fridge runs for four hours instead of twelve — or will not start at all — and conclude the brand lied. It did not. Rated capacity is measured at the cells, and roughly fifteen percent goes to the inverter and the battery's protective reserve before anything reaches your outlet.

Surge is the other one. A compressor can demand two to three times its running watts for a fraction of a second. A unit with plenty of watt-hours and a weak inverter will refuse to start the one appliance you bought it for, and no amount of battery fixes that.

None of this is hidden. It is in the specification sheet and the manual, published and free. These two books teach you to read them — before you pay, and then for the years afterwards.

I

The Backup Power Library

Two books, 121 pages on portable power stations: everything that decides whether the one you are looking at is the right one — and whether it still works in five years.

BOOK ONE Buyer's Guide Before you pay

The Power Station Buyer's Guide

Sizing, chemistry, output and solar — the specifications that decide whether it does the job.

78 pages · 42 field notes across 7 parts · 8 schematic diagrams · sizing worksheet · spec comparison sheet · watt table
$47$27Save $20
  • The number on the box is not the one you get — about 15 percent goes to the inverter and the battery's reserve, which is why sizing on the rated figure leaves people hours short.
  • The surge that stops your fridge starting — a compressor can ask for close to a thousand watts for a fraction of a second, and capacity does not help if the inverter cannot supply it.
  • LFP or NMC decides how many years you get — same watt-hours, same price, and a cycle rating that can differ by a factor of five.
Get Book One — $27
Instant PDF download · 30-day money-back
BOOK TWO Owner's Guide After you pay

The Power Station Owner's Guide

The habits that decide how long it lasts, and the outage plan that makes it useful.

43 pages · 20 field notes across 5 parts · 5 schematic diagrams · outage plan · runtime log · symptom table
$77$47Save $30
  • Storing it at 100 percent is aging it — two free settings, a quarterly reminder, and the difference is measured in years.
  • Most faults are not the battery — a symptom table that separates a $40 charger from a dead pack before you replace anything.
  • Owning one is not having a plan — load priority tiers, fridge cycling and a rehearsed refill route, written down and taped to the unit.
Get Book Two — $47
Instant PDF download · 30-day money-back
BEST VALUE — BOTH BOOKS
BOTH BOOKS The Backup Power Library Buy it right, keep it working

The Backup Power Library

Both books in one purchase — the whole life of a portable power station, from the spec sheet to the recycling bin.

121 pages · 62 field notes · 13 schematic diagrams · every worksheet from both books
$124$59Save $65
THIS ONE PURCHASE INCLUDES BOTH BOOKS:
✓ Book One — The Buyer's Guide$47
✓ Book Two — The Owner's Guide$77

Both PDFs delivered together, instantly. You do not need to buy them separately.

  • Size it, then test it — a worksheet that turns your own appliances into a watt-hour number, and a day-one test plan to run inside the return window.
  • Compare any three units honestly — a spec comparison sheet that reorders most shortlists once it is filled in from the spec sheets rather than the listings.
  • Make it last — storage charge, temperature, the quarterly routine and an annual runtime log that becomes your evidence in a warranty claim.
Get Both Books — $59
Instant PDF download · 30-day money-back
III

What getting it wrong costs

Every figure on the left comes from a field note in these books.

The expensive mistakes

What people actually spend

A unit that cannot start your fridge$500–$2,000
Sizing on rated instead of usable capacity15% short
NMC where LFP belonged, cycled weeklyyears of life
Panels that exceed the input limits$200–$600
Expanding piecemeal instead of buying right$300–$1,000
Storing at 100% in a hot garageyears of life
One of these, once, and the books have paid for themselves several times over.

What the books cost

One payment, keep the files

Book One — Buyer's Guide$27
Book Two — Owner's Guide$47
Both books, The Backup Power Library$59
The method does not expire. Brands here change cell suppliers and abandon model ranges within a year or two, so a list of the best units goes stale fast. The questions in these books do not — including for units that do not exist yet.
IV

Built from the spec sheets, not from listicles

Where the content in these books comes from.

Manufacturer documentation

Specification sheets, manuals and warranty terms — including the figures that appear in the manual but never on the listing.

Published safety standards

The testing-laboratory marks you can verify yourself, and the carbon monoxide standards that matter if a generator is part of your plan.

Arithmetic you can check

Every worked figure in these books is shown with its calculation, so you can repeat it against your own appliances and your own electricity rate.

V

A real page from Book One

Every field note follows the same shape: why it matters, what to do, a non-obvious refinement, and what it saves you.

Output · Field Note

Surge rating and the fridge that will not start

Compressors and motors demand a brief burst far above their running watts.

Appliances with motors or compressors — fridges, freezers, pumps, some power tools — draw a starting surge commonly two to three times their running watts, and sometimes more, for a fraction of a second. A fridge that runs on 150 watts can therefore demand close to a thousand at the instant the compressor kicks in. If the inverter cannot supply that, the fridge fails to start and the unit may cut out, even though its capacity is barely touched.

Check the surge rating against the starting requirement of your most demanding appliance. Starting watts are sometimes on the rating label, sometimes only in the manual, and sometimes obtainable from the manufacturer.

What it saves you: prevents discovering during an outage that a unit bought for the fridge cannot start the fridge.
VI

Both books, one purchase

Your download arrives by email right after checkout. Print the worksheets and keep them with the unit.

Book One — The Power Station Buyer's Guide (78 pages)$47
Book Two — The Power Station Owner's Guide (43 pages)$77
Listed separately: $124
You pay today$59
Get Both Books — $59

Instant PDF download · one payment · 30-day money-back guarantee
The files are yours to keep and print

Our promise

Try the books for 30 days. If they never earn their keep, one email gets you a full refund — and you keep the files. No forms, no questions.

Write to vantsantk@gmail.com.

VII

Common Questions

Everything worth knowing before you order

Which book do I need?+

Shopping right now? Book One. It covers sizing, chemistry, output and surge, charging and solar, and what the whole thing really costs — everything up to the moment you pay. Already own one? Book Two is the habits that decide how long it lasts, plus the outage plan and troubleshooting. Both together are $59, which is less than the two separately.

Do these cover generators?+

Not as a subject of their own. Both books are about portable power stations. Generators appear as a comparison — there is a full field note weighing the two honestly — and as a charging route, since a modest battery plus a small inverter generator is often the strongest household setup. A dedicated generator guide will join The Backup Power Library later.

Do you recommend specific brands and models?+

Deliberately very few. Manufacturers in this category change cell suppliers, launch and abandon model ranges, and are replaced by new entrants within a year or two, so a list of the best units is unreliable by the time you read it. Instead you get the questions to ask of any unit, a spec comparison sheet to fill in for your own shortlist, and a way to judge a manufacturer's platform rather than its marketing.

I have not bought anything yet. Is this too technical?+

No. Book One starts by building a load list from your own appliances, which is arithmetic you can do with a plug-in watt meter and a calculator. Every term is defined in the glossary, every worked figure shows its calculation, and the reference section includes a sizing worksheet and a ten-point check you can run on your phone in the store.

Is this US-specific?+

Mostly not. The sizing, specifications, chemistry and maintenance work anywhere. Prices are in US dollars, electricity-cost examples use US rates, and the safety certifications named are the US ones. Readers elsewhere should check their own national marks in place of those.

What format are the books in?+

PDFs, downloadable immediately after purchase. Read them on any device or print them — the worksheets, checklists and runtime log are designed to be printed and kept with the unit. No subscription, no app. Once you have the files, they are yours.

Read the spec sheet. Then buy.

Both books, 121 pages, delivered instantly.

Get Both Books — $59