As the UK accelerates towards net-zero emissions, with heat batteries gaining traction in the renewable energy market, Sunamp Thermino stands out as a leading solution for efficient hot water storage. Searches for "best heat batteries UK" and "solar compatible hot water systems" are surging, reflecting growing interest in eco-friendly alternatives to traditional cylinders. In this expert guide, we'll explore the Sunamp Thermino range, detailing how it works, its key features, and seamless integration with solar PV systems. Whether you're a homeowner upgrading your heating or an installer seeking reliable, space-saving options, Thermino offers premium performance backed by positive Sunamp reviews for energy savings and sustainability.
What is the Sunamp Thermino Heat Battery?
The Sunamp Thermino is an innovative thermal energy storage system that replaces conventional hot water cylinders with compact, high-efficiency heat batteries. Using patented phase change material (PCM) called Plentigrade, it stores thermal energy for on-demand hot water, making it ideal for UK homes transitioning to low-carbon heating. The range includes:
- Thermino ePlus: Direct water heaters powered by grid electricity or solar PV, available in 70L, 150L, 210L, and 300L equivalent sizes.
- Thermino xPlus: Indirect water heaters compatible with boilers, heat pumps, and solar PV, in 150L, 210L, and 300L equivalents.
Over 30,000 units have been installed across homes and commercial buildings, praised in reviews for their compactness—up to four times smaller than traditional cylinders—and low maintenance. This makes Thermino perfect for space-constrained properties, new builds, or retrofits.
How Does the Sunamp Thermino Heat Battery Work?
At its core, the Thermino uses phase change technology to store and release heat efficiently. Unlike traditional water tanks that store hot water directly, Thermino employs Plentigrade PCM, which absorbs heat as it changes from solid to liquid and releases it when reverting to solid. This allows it to store up to four times more energy than an equivalent volume of water, with ultra-low heat losses—up to four times lower than conventional cylinders.
Here's a step-by-step breakdown:
- Charging Phase: The battery is heated by an embedded electric element (2.8kW rating) or external sources like a heat pump or boiler. For ePlus models, it connects directly to the grid, shifting demand to off-peak tariffs for cost savings. xPlus models use a heat exchanger coil for indirect heating.
- Storage: The PCM melts at around 58°C, storing thermal energy densely without the need for large volumes. A simple user interface shows charge status.
- Discharging Phase: When hot water is needed, cold mains water flows through a high-powered heat exchanger, absorbing stored heat to deliver instant, mains-pressure hot water at high flow rates (up to 25L/min).
- Backup and Control: An internal heating element provides backup, ensuring constant supply. The system includes a thermostatic mixing valve for safe temperatures and can integrate with timers or building controls.
This process minimizes energy waste, with standby losses as low as 0.48 kWh/24h for smaller models, compared to 1.344–3.336 kWh in older cylinders. Reviews highlight its quiet operation and reliability, with no mandatory annual maintenance and a 10-year warranty on the element and core.
Watch this explainer video for a visual demonstration of the Thermino in action:
Key Features and Components
Sunamp Thermino boasts installer-friendly design and robust components:
- Compact and Flexible: Plumbing exits on three sides for versatile orientation; modular setup allows series/parallel connections for larger capacities.
- Energy Efficiency: A+ rating for xPlus models, C for ePlus; low legionella risk due to no stored water.
- Components: Includes high-quality brass push-fit connectors, expansion vessel, pressure relief valve, and optional Sunamp timer.
- Compatibility: Works with any energy source via Optimino keys—simple upgrades without replacing the unit.
In hard water areas, a water conditioner like Hydroflow HS38 is recommended to maintain warranty.
Solar PV Compatibility: Maximizing Renewable Energy
One of Thermino's standout features is its seamless integration with solar PV systems, addressing rising searches for "solar compatible hot water systems UK". By adding the Optimino PV key (ePV for ePlus or vfPV for xPlus), the battery captures surplus solar energy that would otherwise be exported to the grid, storing it as heat for hot water.
- How It Integrates: Solar PV panels generate electricity, diverted via a device like MyEnergi Eddi to charge the battery. Off-peak grid top-ups ensure reliability.
- Benefits: Increases self-consumption, reduces bills, and cuts carbon emissions. Reviews note up to 50% lower heat loss than standard cylinders, enhancing solar efficiency. Pair with heat pumps for even greater savings.
- Future-Proofing: Easy key swap for PV addition, making it ideal for homes with existing or planned solar setups.
This compatibility unlocks renewables, with users reporting significant cost reductions and eco-friendly performance.
Benefits of Sunamp Thermino Heat Batteries
- Space and Cost Savings: Up to 4x more compact, freeing cupboard space; shifts to off-peak tariffs for lower bills.
- Energy Efficiency: Reduces consumption by 80% in heating-focused homes; A+ efficiency cuts emissions.
- Reliability and Low Maintenance: 10-year warranty, no annual servicing, minimal legionella risk.
- Versatility: Suits flats to family homes; scalable for larger demands.
Sunamp reviews consistently praise its performance with solar and heat pumps, noting quick installations and value for money.
Technical Specifications at a Glance
| Model | Type | Heat Storage (kWh) | Equivalent Cylinder (L) | V40 Volume (L) | Standby Loss (kWh/24h) | Efficiency Rating | Dimensions (H x W x D mm) | Flow Rate (L/min) |
|---|---|---|---|---|---|---|---|---|
| Thermino 70 ePlus | Direct | 3 | 74 | 105 | 0.48 | C | 575 x 365 x 440 | 6 |
| Thermino 150 ePlus | Direct | 6 | 142 | 199 | 0.68 | C | 650 x 365 x 575 | 15 |
| Thermino 210 ePlus | Direct | 9 | 212 | 301 | 0.77 | C | 860 x 365 x 575 | 20 |
| Thermino 300 ePlus | Direct | 12 | 306 | 436 | 0.84 | C | 1070 x 365 x 575 | 25 |
| Thermino 150 xPlus | Indirect | 7 | 142 | 185 | 0.68 | A+ | 650 x 365 x 575 | 15 |
| Thermino 210 xPlus | Indirect | 10.5 | 212 | 300 | 0.77 | A+ | 860 x 365 x 575 | 20 |
| Thermino 300 xPlus | Indirect | 14 | 284 | 370 | 0.84 | A+ | 1070 x 365 x 575 | 25 |
Why Choose Aizo Quality Heating for Your Sunamp Thermino?
At Aizo Quality Heating, we specialize in Sunamp supply, ensuring seamless service from purchase to delivery. Our accredited team handles everything, including removal of old systems if required. Due to the units' weight (up to 75kg net), we provide specialized delivery—carefully transporting and even carrying upstairs if needed, avoiding DIY hassles. With positive feedback on our professional, efficient service, we're your trusted partner for heat batteries UK.
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