This video explores flow-through heaters (FTHs), a relatively new heating technology used in espresso machines. The speakers discuss how FTHs work, their advantages (faster heating, better temperature consistency, energy efficiency), disadvantages, and their evolution within the espresso machine market, highlighting various models that utilize this technology.
Flow-Through Heaters (FTHs) Explained: FTHs are small, efficient heating elements that heat water quickly and precisely. They offer significant advantages over traditional boilers and thermoblocks in terms of speed and energy efficiency.
Historical Overview of FTHs: The technology originated around 2007 with a company called Pharaoh, initially used in pad machines. Sage (Breville outside of Europe) was an early adopter, integrating FTHs into machines like the Bambino Plus and Barista Pro.
Comparison with Boilers and Thermoblocks: Boilers are inefficient due to the large volume of water they heat, leading to high energy consumption. Thermoblocks are a faster alternative but still heat a larger mass than FTHs. FTHs heat only the necessary amount of water, making them significantly more energy-efficient and faster.
Advantages of FTHs: Instantaneous heating, energy efficiency, precise temperature control, and ease of descaling are key advantages.
Market Adoption and Future Trends: Many espresso machine manufacturers have adopted FTH technology, with improvements in control systems leading to even better performance. The video mentions several machines using FTHs, highlighting the Zura and Maro as examples of superior implementation.
The two main heating elements commonly used in espresso machines besides the flow-through heater are boilers and thermoblocks. Boilers, often dual boilers in some machines, can range from slightly smaller (around one liter or less) to much larger capacities (8-10 liters in some gastronomy machines). They heat a large volume of water, leading to significant energy consumption and slower heating times. Thermoblocks, typically found in fully automatic machines, heat a smaller mass of aluminum (300-500g), resulting in faster heating than boilers, but still heat more mass than FTHs and use more energy than FTHs.
Flow-through heaters (FTHs) offer several key advantages over boilers and thermoblocks in terms of heating time and energy efficiency. FTHs provide instantaneous heating, reaching boiling point in one or two seconds, significantly faster than boilers or thermoblocks. Because FTHs heat only the precise amount of water needed for each brewing cycle, they are far more energy-efficient than boilers which heat a much larger volume of water. The video estimates that FTHs use double, triple, or even quadruple less energy than boilers.
