The power went out across three northern European countries last April. In most homes, nothing worked. In some, the lights stayed on, the fridge kept running, and the router stayed connected. The difference was not luck or location. It was a home battery sitting in the corner of a room, fully charged.
That gap is going to widen. Europe’s grid is under more pressure than it has been in decades, not because of one cause but because of several at once: ageing infrastructure, more variable weather, and rapidly growing demand from heat pumps, EV chargers, and data centres. The grid will not fail every day. But it will fail more often than it did ten years ago, and the cost of being unprepared when it does is no longer abstract.
This guide compares three home battery systems priced for a serious home, not a camping kit: the EcoFlow DELTA Pro original (EUR 1,699, close-out pricing), the Bluetti AC500+B300S (EUR 2,799), and the EcoFlow DELTA Pro 3 (EUR 3,299). All three can run a household through a multi-day outage. All three are priced as capital goods, not gadgets. The question is which one earns its place in the house you live in now.
What all three get right
Every unit in this comparison uses lithium iron phosphate chemistry. LFP is the right choice for a battery that will sit in a hallway or utility room and cycle daily for years. It does not run away thermally, it degrades far more slowly than nickel manganese cobalt, and it retains its capacity through several thousand charge cycles with minimal loss. If you are spending more than EUR 1,500 on a home battery, LFP should be the floor, not a premium feature. All three units meet it.
All three also offer genuine expandability. The AC500 scales to 18,432Wh with six B300S batteries attached. The DELTA Pro 3 reaches 12kWh with additional modules. The original DELTA Pro expands beyond its 3.6kWh base with EcoFlow’s Smart Generator or extra battery units. None of these are units you outgrow quickly. If your energy needs grow, your hardware grows with them.
And all three support substantial solar input, which matters more than most buyers consider when they first look at home batteries. A battery that cannot be recharged from renewable sources is only useful during a short outage, not a prolonged one. Solar input is what converts a backup appliance into an energy-independent installation.
Where they differ
The DELTA Pro original is a previous generation that EcoFlow is clearing at EUR 1,699, down from EUR 2,199. The core specifications remain solid: 3.6kWh base capacity, up to 7,200W AC output, LFP chemistry, and EcoFlow’s established service network across Europe. The problem is availability. It was sold out on eu.ecoflow.com at the time of writing. If it returns to stock, it represents strong value for a smaller home or as a first unit in a future multi-unit setup. If it does not, the price advantage disappears entirely and there is nothing left to recommend.
The Bluetti AC500+B300S is the current sweet spot. At EUR 2,799 for the combined unit, you get 3,072Wh of usable storage, a 5,000W inverter rated for continuous use, and 10,000W peak output for motor-heavy appliances like washing machines and heat pumps that pull hard on start-up. The B300S battery module includes automatic heating, which matters in Nordic and Alpine conditions where unheated storage spaces drop cold enough to affect LFP performance in winter. The system expands to 18,432Wh with additional B300S units, which is the widest expansion path in this comparison. The standard warranty is four years. Bluetti’s European distribution runs partly through specialist importers rather than a direct EU storefront, so check lead time and post-sale service responsiveness before you commit. The unit is available to order through poweroak.eu now.
The EcoFlow DELTA Pro 3 is the premium option and the most capable unit for a permanent installation. At EUR 3,299 it costs EUR 500 more than the Bluetti. For that premium you get a newer platform: 4kWh base capacity expandable to 12kWh, a 4,000W continuous inverter with X-Boost handling up to 6,000W for high-draw appliances, 2,600W solar input, and a switchover time of 10 milliseconds that keeps NAS drives and sensitive electronics from registering the outage at all. It operates at 30 dB at a 2,000W load, which is quiet enough for a living room. It charges from flat to 80 per cent in under an hour, which matters when you need to top up before a forecast storm. The standard warranty is five years. The limitation at the time of writing is the same as the original: sold out on eu.ecoflow.com. EcoFlow restocks on a regular cycle. If you need a unit this week, this is not it. If you can wait, it is worth waiting for.
The recommendation
The Bluetti AC500+B300S is the right choice for most buyers at this price point. The 3,072Wh capacity handles a European family home through a 24 to 48-hour outage with sensible load management. The 5,000W inverter covers real domestic loads. The expansion path to 18,432Wh is the widest in this comparison. It is available to order now at a confirmed EU price.
If the EcoFlow DELTA Pro 3 returns to stock and lead time is not a concern, the EUR 500 premium is justified for a permanent installation: a newer platform, five-year warranty, faster recharge, and quieter operation. For a long-term buy, it is the stronger asset.
The DELTA Pro original at EUR 1,699 is worth considering if stock returns. Do not plan around it.
Why this matters now
A home battery is not a luxury item. It is infrastructure for a grid that is becoming less reliable, not more. The materials inside these units – lithium, iron phosphate, copper, aluminium – are rising in cost as demand from EVs, industrial storage, and data centres compounds year on year. The EUR 2,799 you spend today buys more capability per euro than the same unit will cost in three years.
The engineering that designed these systems gets cheaper with every model cycle. The metals that built them do not.
For more context on how to think about your home’s energy resilience, see our piece on what energy sovereignty actually means. If a portable solution better fits your situation, our portable battery buying guide for 2026 covers the EUR 500 to EUR 1,500 range.
Check current availability and price: Bluetti AC500+B300S at poweroak.eu
Check current availability and price: EcoFlow DELTA Pro 3 at eu.ecoflow.com
Links above route to manufacturer sites. Affiliate tracking is pending programme confirmation; no commission is currently earned from this guide. Full disclosure policy.