What Is a Thermal Battery—and Why You’ll Never Go Back to Traditional Water Heaters

Evan DeMarco
July 15, 2025

What Is a Thermal Battery—and Why You’ll Never Go Back to Traditional Water Heaters

Why Hot Water Needs a Smarter Solution

Most homes and commercial buildings still rely on outdated technologies—tank or tankless water heaters—to deliver hot water. These systems waste energy, suffer from inconsistent temperatures, and often require frequent maintenance. Worse, they run during peak electricity hours, driving up energy costs and placing unnecessary stress on the grid.

What Is a Thermal Battery?

A thermal battery is a device that stores energy in the form of heat rather than electricity. Instead of heating water on-demand, it absorbs energy from sources like solar, grid power, or heat pumps and stores that energy in a Phase Change Material (PCM). When hot water or heat is needed, the battery releases that stored thermal energy instantly and efficiently.

Why SolThera Is Different

SolThera’s thermal batteries use a stable, non-corrosive PCM that provides decades of reliable performance—unlike older systems that rely on salt-based materials. Each unit is NSF-61 certified for potable water, includes full onboard diagnostics, and seamlessly integrates with solar, heat pumps, and radiant systems. SolThera stores energy off-peak and releases it exactly when it’s needed—reducing both your energy bills and your carbon footprint.

Tank vs. Tankless vs. Thermal Battery: What the Numbers Say

Traditional tank systems constantly reheat water, leading to standby losses and inefficiency. Tankless heaters improve on this but still rely on high-draw electric or gas inputs. SolThera’s thermal batteries, by contrast, operate with over 95% efficiency and drastically reduce peak energy usage. Over a 10-year period, the cost savings can be thousands of dollars—not to mention reduced maintenance headaches.

Thermal Batteries Are the Future of Water Heating

As we transition to a decarbonized, electrified grid, thermal batteries are a necessary upgrade—not just a luxury. They align with electrification codes, ease the burden on HVAC systems, and position your home or building for long-term energy resilience. SolThera is leading the charge with a smarter, safer, and more sustainable solution.


Call to Action:

Ready to upgrade your water heating system? Explore SolThera’s smart thermal batteries today and take the first step toward clean, efficient energy.