An integral part of modern heating systems of any buildings is a heat accumulator. This device (tank or buffer tank) is designed to accumulate and store thermal energy received from various sources, and then use it as needed in heat and water supply systems. At the same time, the heat accumulator almost completely prevents heat loss and significantly reduces resource consumption.
Short description
In fact, the buffer tank of the heating system is a huge thermos in the form of a vertical steel tank - a cylinder with insulated walls. Its height, as a rule, is much greater than the diameter (3-5 times). Heat-resistant foam insulation reduces heat loss through the tank walls.
In the heating system, the heat accumulator occupies a place between the heat circuit and the heating devices, so that the heated water first enters the tank, and only then into the radiators and other heating devices.
Benefits of buffer tanks
The heat accumulator (buffer tank) allows you to efficiently use the energy of heat sources that may be temporarily unavailable. For example, solid fuel boilers give off heat only during the burning of wood or coal, heat from solar systems can only be used on sunny days, energy from an electric boiler or heat pump is best used at night at a reduced rate in order to save money. While these sources are working, the heat is supplied regularly, but what to do when the firewood burns out or the sun hides behind the clouds? In this case, the main advantage of buffer storage is manifested: accumulating excess thermal energy during intensive operation of heat sources, the buffer capacity stores it for quite a long time (up to 6 days) and, as necessary, spends it on the needs of the consumer.
The thermal accumulator makes it possible to correctly and clearly coordinate the processes of generation and release of thermal energy in terms of power, time and temperature. In addition, the buffer tank protects the heating system from boiler overheating.
Working principle
The principle is really simple. A heat generator of any kind during operation gives off its thermal energy to a buffer tank (associated with a battery, a charging process takes place). The heat is then used by the heating system to maintain a comfortable temperature in the rooms (discharging process).
Buffer tank is a necessary element of a combined heat supply system, high-temperature (gas boilers, solid fuel, electric) and low-temperature (heat pump power plants, solar collectors) heat sources can be simultaneously connected to it.
Calculation of buffer capacity
It is quite difficult to calculate the volume of the storage tank so that the room has a comfortable temperature with the smallest possible tank size, only a heat engineer can do it. Practice shows that the smallest capacity volume can be taken at the rate of 25 liters per 1 kW of boiler power (but not less), the optimal volume is twice as much.
The feasibility of using heat accumulators (buffer tanks) has been proven by European experience both in economic terms and in terms of safety and reducing the risk of overheating of the coolant. The only drawback is the large volume of the tank and the need for additional space for its installation. Nevertheless, at present, the storage tank is not just a profitable option, but an essential element in combined heat supply systems.
