Thermal energy storage (TES) enhances the efficiency of heating and cooling buildings by storing thermal energy when it is abundant or inexpensive and releasing it when needed, thereby better matching energy availability with demand. This approach reduces peak loads, improves energy use efficiency, and enables integration with renewable energy sources.
How TES Enhances Efficiency in Building Heating and Cooling
- Time-shifting thermal energy use: TES systems store heat or cold when it is available, often off-peak or from renewable sources like solar or wind, and release it later when heating or cooling demand occurs. This reduces the need to generate or purchase energy at peak times, lowering costs and grid strain.
- Peak load reduction: By offsetting heating and cooling demands during peak periods, TES reduces the maximum energy consumption, allowing HVAC systems to operate more efficiently and potentially downsizing system capacity requirements.
- Improved HVAC system performance: TES can provide a more stable thermal source for heat pumps and other HVAC equipment, improving their coefficient of performance and overall energy efficiency.
- Use of phase change materials (PCMs): TES often involves materials that store/release heat at near room temperature through melting and freezing cycles. These phase changes help maintain comfortable indoor temperatures with less electric energy needed for active heating or cooling. For example, a PCM that melts and freezes around 70°F can absorb excess heat when indoor temperature rises and release heat when temperature drops, naturally smoothing temperature fluctuations.
- Long-term and seasonal storage: Some TES technologies, such as storage using dehydrated salts, can hold thermal energy for prolonged periods without significant losses, enabling seasonal storage of heat or cold and better utilization of intermittent renewable energy resources.
- Thermal mass utilization: The building structure itself or dedicated storage tanks can act as thermal batteries, storing heat or coolness and releasing it slowly, which increases indoor comfort and reduces HVAC cycling.
Summary
| Benefit | Explanation |
|---|---|
| Time-shifting of energy | Stores thermal energy when available, uses it when needed, balancing supply and demand |
| Peak load reduction | Lowers peak HVAC energy demand for better system efficiency and smaller equipment sizing |
| Enhanced HVAC operation | Provides stable thermal conditions, improving heat pump and system efficiency |
| Use of PCMs | Absorbs/releases heat at near-room temperatures for temperature regulation with less energy use |
| Seasonal storage | Enables long-term storage of heat/cold, supporting renewable energy integration |
| Thermal mass storage | Utilizes building materials or tanks as thermal batteries for comfort and energy savings |
In essence, TES technologies turn buildings into thermal batteries, enhancing comfort and reducing energy consumption and costs associated with heating and cooling. This makes TES a key component in advancing energy-efficient, sustainable building designs.
Original article by NenPower, If reposted, please credit the source: https://nenpower.com/blog/how-does-thermal-energy-storage-enhance-the-efficiency-of-heating-and-cooling-buildings/
