Demystifying Thermal Energy: Your Guide to Decarbonizing Heat in Homes and Buildings
Evan DeMarco
May 5, 2025
đĄď¸ Heating Is the Elephant in the (Boiler) Room
When people talk about clean energy, most of the conversation centers on electricity. But if weâre serious about tackling climate change and building for the future, thereâs a bigger and more immediate challenge hiding in plain sight: heat.
Heating and hot water systems account for over 40% of global energy use, and most of that still comes from fossil fuelsânatural gas, oil, and outdated electric resistance systemsăsource: IEAă.
To create buildings that are truly sustainable, we must decarbonize heatâand that means rethinking how we generate, store, and deliver thermal energy.
đĽ What Is Thermal EnergyâAnd Why Does It Matter?
Thermal energy is the energy associated with heat. In the built environment, it powers:
Space heating
Domestic hot water
Radiant floor systems
Industrial and commercial HVAC loads
Unlike electricity, heat is harder to store efficientlyâespecially over time. Most legacy solutions rely on brute-force heating (think: hot water tanks or boilers) that waste energy and struggle to integrate with renewable systems.
Thatâs where thermal energy storage (TES) comes in.
đ Understanding Thermal Energy Storage Methods
Thermal energy storage systems are essential for stabilizing supply and demand, particularly with intermittent renewable energy sources like solar. But not all TES systems are created equal.
Hereâs how the most common systems stack upâand where they fall short.
1. Sensible Heat Storage
How it works: Stores energy by increasing the temperature of a material (like water, concrete, or molten salts) without changing its phase.
Drawbacks:
Significant heat loss over time due to temperature gradients.
Requires large physical volumes to store meaningful energy.
Efficiency: 50â90%, depending on insulation and usage designăsource: EESIă.
2. Latent Heat Storage Using Traditional PCMs
How it works: Uses the phase change (solid â liquid) of materials to absorb and release heat.
Benefits:
Higher energy density
Stable temperature control during phase change
Drawbacks:
Low thermal conductivity leads to slow heat transfer
Some PCMs degrade over time, reducing efficiency
Efficiency: Up to 90% in ideal setupsăsource: SolarPACESă.
3. Thermochemical Storage
How it works: Uses reversible chemical reactions to store and release energy.
Potential:
Extremely high energy density
Great for seasonal storage and long-duration applications
Challenges:
Expensive, complex, and still under development
Efficiency: Highly variable; not yet practical at scale.
â ď¸ The Problem with Traditional TES Systems
Despite decades of development, most thermal storage systems struggle with:
đĽ High standby losses (especially in tank-based systems)
𧹠Bulky infrastructure thatâs hard to retrofit
â ď¸ Material fatigue and degradation
â Poor integration with renewables or smart home technology
They were designed for a world before carbon mandates, gas bans, and climate accountability.
đ Soltheraâs PCM-Based Thermal Battery: Designed for the Future
Solthera leverages advanced phase change material technologyâbut improves on traditional PCM systems with:
Engineered thermal conductivity enhancers for faster charging/discharging
Non-toxic, non-flammable PCMs with long cycle lives
Integrated insulation and compact design that dramatically reduces heat loss
How It Works:
Solthera absorbs heat (from solar, heat pump, or grid)
PCM material meltsâstoring energy
When hot water is needed, PCM solidifiesâreleasing that heat
The cycle repeats, efficiently and silently, with no moving parts
đ At a Glance: How Solthera Outperforms Other TES Systems
â
đ Real-World Ready for Residential + Commercial Projects
Soltheraâs thermal battery is already being deployed in:
Smart campuses
All-electric homes
Federal and state buildings
High-performance green projects
Itâs especially valuable in jurisdictions with:
Gas appliance bans
Electrification mandates
ESG goals and carbon reporting requirements
â A Clear Path to Decarbonized Heat
Solthera is more than a productâitâs a building block for the clean energy transition.
With up to 95% system efficiency, zero emissions, easy installation, and tight integration with renewable energy sources, it delivers what older systems canât:
