Don't Buy a Home Battery System Until You Watch This!
Spirit Energy
82,437 views
The battery is the single most expensive piece of hardware in a solar and battery storage system and the decision you make at the point of installation shapes everything that comes after it. Your EV charger, your app, your tariff management, your ability to earn income from the grid: all of it flows from the system you install first. The choice you make now needs to still be the right choice in ten years' time.
In this video, we compare the three best home battery storage systems available in the UK right now: the Tesla Powerwall 3, the Sigenergy SigenStor, and the Fox EVO. Spirit Energy has been installing solar and battery storage since 2010. We installed the first Powerwall 3 in the UK and are a leading Sigenergy installer. We go through every metric that matters — not just the headline specs, but what each one actually means for your home, your bills, and your long-term return.
The Powerwall 3 gives you 13.5 kWh per unit with DC expansion packs available. The SigenStor uses a modular stack system — mix and match module sizes to hit almost any capacity target. The Fox EVO offers 9.73 kWh per unit with up to three units in parallel. On inverters, the key difference is the Powerwall 3's fully software-configurable output rating — if your DNO allowance changes after installation, there's no hardware swap needed. The Fox EVO charges and discharges at the full 10 kW rate in both directions and charges from flat in approximately 58 minutes, which is considerably faster than the other two.
On power cut protection, the SigenStor is the only one of the three that can back up a three-phase supply, and both the Fox and Sigenergy can operate completely off-grid — something the Powerwall 3 cannot. All three apps offer comprehensive monitoring and AI-driven scheduling. The Powerwall 3 leads on thermal management with predictive preconditioning based on weather forecasts. The Fox EVO actively manages temperature in both directions; the SigenStor's approach is more passive. Both the Fox EVO and SigenStor can participate in the Axle Energy virtual power plant scheme right now, paying £1 per kWh during grid stress events. Tesla's equivalent is coming when it launches as a UK electricity provider, and at Tesla's scale it has the potential to be the most significant of the three.
On price, the spread between all three systems is less than 4% when measured on cost per usable kWh including the backup gateway. The Fox EVO is the most affordable, the Powerwall 3 roughly 3% higher, the SigenStor around 4% above the Fox. At that margin, the decision comes down to capability, flexibility, and warranty — 10 years on the Powerwall 3 with no throughput limit, 10 years extendable to 15 on the SigenStor, and 12 years on the Fox EVO.
Get a quote from Spirit Energy: https://www.spiritenergy.co.uk/reques...
Battery comparison table:
https://info.spiritenergy.co.uk/batte...
Design your own solar & battery system:
https://www.spiritenergy.co.uk/solar-...
Chapters
0:00 Introduction — Tesla Powerwall 3 vs Sigenergy SigenStor vs Fox EVO
2:22 Battery capacity and expandability
5:33 Inverter performance and solar input
11:39 Charge and discharge rates
13:39 Power cut protection and backup
16:40 App and software
20:16 Thermal management
22:38 EV charging compatibility
25:57 Build quality, fire safety, and special features
30:58 Price and warranty
34:33 Verdict — which battery is right for you?
Request a quotation from Spirit Energy: https://www.spiritenergy.co.uk/reques...
Watch on of our client's solar journey which shows the process of getting solar from point of enquiry through to the design, survey, modelling, project management, installation, and handover: Sam's Solar Journey
Visit our website - https://www.spiritenergy.co.uk/
Try our Free Solar Calculator - https://www.spiritenergy.co.uk/solar-...
Try our Free Battery Storage Calculator - https://www.spiritenergy.co.uk/solar-...
Follow us on LinkedIn - LinkedIn: spirit-solar-ltd
Follow us on Instagram - Instagram: spiritenergy_uk
Follow us on Facebook - Facebook: SpiritEnergyUK
Follow us on X / Twitter - https://x.com/SpiritEnergy_UK
20 Comments
It’s a shame you don’t cover my area.
My biggest takeaway from this video, given that I am very interested in the energy arbitrage aspect and other ways of earning money from energy supply to the grid when it is seeing heavy demand, is that I might wait to see exactly what happens when Tesla enters the UK energy supplier market because if what’s on offer in the UK is anywhere close to those USA numbers you mentioned that might be an overwhelming advantage for the Powerwall vs the others (at least for me).
Don't Buy a Home Battery System Until You Watch This!
Spirit Energy
82,437 views
The battery is the single most expensive piece of hardware in a solar and battery storage system and the decision you make at the point of installation shapes everything that comes after it. Your EV charger, your app, your tariff management, your ability to earn income from the grid: all of it flows from the system you install first. The choice you make now needs to still be the right choice in ten years' time.
In this video, we compare the three best home battery storage systems available in the UK right now: the Tesla Powerwall 3, the Sigenergy SigenStor, and the Fox EVO. Spirit Energy has been installing solar and battery storage since 2010. We installed the first Powerwall 3 in the UK and are a leading Sigenergy installer. We go through every metric that matters — not just the headline specs, but what each one actually means for your home, your bills, and your long-term return.
The Powerwall 3 gives you 13.5 kWh per unit with DC expansion packs available. The SigenStor uses a modular stack system — mix and match module sizes to hit almost any capacity target. The Fox EVO offers 9.73 kWh per unit with up to three units in parallel. On inverters, the key difference is the Powerwall 3's fully software-configurable output rating — if your DNO allowance changes after installation, there's no hardware swap needed. The Fox EVO charges and discharges at the full 10 kW rate in both directions and charges from flat in approximately 58 minutes, which is considerably faster than the other two.
On power cut protection, the SigenStor is the only one of the three that can back up a three-phase supply, and both the Fox and Sigenergy can operate completely off-grid — something the Powerwall 3 cannot. All three apps offer comprehensive monitoring and AI-driven scheduling. The Powerwall 3 leads on thermal management with predictive preconditioning based on weather forecasts. The Fox EVO actively manages temperature in both directions; the SigenStor's approach is more passive. Both the Fox EVO and SigenStor can participate in the Axle Energy virtual power plant scheme right now, paying £1 per kWh during grid stress events. Tesla's equivalent is coming when it launches as a UK electricity provider, and at Tesla's scale it has the potential to be the most significant of the three.
On price, the spread between all three systems is less than 4% when measured on cost per usable kWh including the backup gateway. The Fox EVO is the most affordable, the Powerwall 3 roughly 3% higher, the SigenStor around 4% above the Fox. At that margin, the decision comes down to capability, flexibility, and warranty — 10 years on the Powerwall 3 with no throughput limit, 10 years extendable to 15 on the SigenStor, and 12 years on the Fox EVO.
Get a quote from Spirit Energy: https://www.spiritenergy.co.uk/reques...
Battery comparison table:
https://info.spiritenergy.co.uk/batte...
Design your own solar & battery system:
https://www.spiritenergy.co.uk/solar-...
Chapters
0:00 Introduction — Tesla Powerwall 3 vs Sigenergy SigenStor vs Fox EVO
2:22 Battery capacity and expandability
5:33 Inverter performance and solar input
11:39 Charge and discharge rates
13:39 Power cut protection and backup
16:40 App and software
20:16 Thermal management
22:38 EV charging compatibility
25:57 Build quality, fire safety, and special features
30:58 Price and warranty
34:33 Verdict — which battery is right for you?
Request a quotation from Spirit Energy: https://www.spiritenergy.co.uk/reques...
Watch on of our client's solar journey which shows the process of getting solar from point of enquiry through to the design, survey, modelling, project management, installation, and handover: Sam's Solar Journey
Visit our website - https://www.spiritenergy.co.uk/
Try our Free Solar Calculator - https://www.spiritenergy.co.uk/solar-...
Try our Free Battery Storage Calculator - https://www.spiritenergy.co.uk/solar-...
Follow us on LinkedIn - LinkedIn: spirit-solar-ltd
Follow us on Instagram - Instagram: spiritenergy_uk
Follow us on Facebook - Facebook: SpiritEnergyUK
Follow us on X / Twitter - https://x.com/SpiritEnergy_UK