Backup gear is unusual to review, because the thing you're buying is behaviour during an event that hasn't happened yet. A unit can look excellent for eleven months and disappoint the one night it matters.
Everything in home backup reviewed here was bought at retail and kept in service. Here's how I score it and what the spec sheet won't tell you.
How I score a product
- Does it carry the loads it claims? Measured against a real appliance list, not a capacity figure.
- Switchover behaviour. How fast, whether it's automatic, and whether anything sensitive — a desktop, a router, a medical device — actually notices the transition.
- Living with it. Standby drain over months, noise in a space people occupy, how much of the display and app you end up using.
- Honest value at installed cost. Including the electrical work, since that's what you'll actually pay.
- What breaks the deal. Usually expansion pricing, or a recharge limitation that only surfaces in a long outage.
Scores cluster between 4 and 5 because I don't buy systems I expect to be bad. The gap between a 4.3 and a 4.6 is where the useful information sits — the rubric is in how I rate products.
What a spec sheet won't tell you
Standby drain. A backup battery spends almost all its life sitting full and waiting. A unit that quietly loses charge over months is a poor backup device however large its battery is, and this figure is rarely published.
What expansion actually costs. Modular systems advertise the capability, not the price. Expansion modules that cost nearly as much as the base unit change the entire value case, and you only find that out at checkout.
Whether it recharges from solar while the grid is down. Not the same as being solar-compatible. Some systems only accept solar input while grid-connected, which is precisely backwards for outage use, and it's the specification most worth confirming directly.
Noise where it lives. These units are bigger than portable stations and their fans are correspondingly louder. If it's going in a hallway or a bedroom closet, that matters more than any spec.
Which review you want
If you're looking at the top of the ladder — whole-home capability, expandable capacity, automatic switchover — read the EcoFlow Delta Pro Ultra review. It's the system that most directly competes with a permanently installed wall battery, and the review covers where that comparison holds up and where it doesn't.
If you haven't yet decided whether you need this class of system at all, read home battery vs portable power station first — it's the cheaper question to answer. To size before you shop, use my home backup buying guides, and to sanity-check any capacity claim against your own outage, the home backup calculators.
