Several types of boilers vary in efficiency depending on their design, fuel type, and application. Here are some of the most efficient boiler types:
- Condensing boilers: Condensing boilers are highly efficient because they utilize the latent heat in the flue gases. They have a secondary heat exchanger that extracts additional heat from the exhaust gases, allowing them to achieve efficiency levels of over 90%. Condensing boilers are commonly fueled by natural gas or propane.
- Combi boilers (combination boilers): Combi boilers are compact units that provide both central heating and hot water on demand. They are highly efficient because they eliminate the need for a separate hot water storage tank, reducing heat loss and energy consumption. Combi boilers can be condensing or non-condensing, with condensing models being the most efficient.
- Biomass boilers: Biomass boilers use organic materials such as wood pellets, chips, or logs as fuel. They can be highly efficient and environmentally friendly, particularly if the biomass is sourced sustainably. Biomass boilers typically have high efficiency ratings and can provide both heating and hot water.
- Heat pumps: Heat pumps extract heat from the air, ground, or water and transfer it into a building for heating purposes. They can achieve high levels of efficiency, especially in moderate climates. Heat pumps are available in various types, including air source heat pumps, ground source heat pumps (geothermal), and water source heat pumps.
- Solar thermal systems: Solar thermal systems use solar collectors to capture sunlight and convert it into heat for water heating or space heating. While their efficiency depends on factors such as climate and system design, solar thermal systems can be highly efficient, particularly in sunny regions.