UA solar system consists of the solar collector, the storage subsystem, the system energy transport (pipelines, pumps, heat exchangers) and the system of Service or consumer system of solar energy captured. In their design must take into consideration that, as important as the correct selection of the elements of each subsystem, the correct integration of all in the system and the selection of strategies for control and operation regulations.

With all this,the annual performance of the system, which will depend on the technology used, will depend primarily on the following factors:

  • Collector: operating parameters η0 (optical efficiency, solar energy gain) and UL (thermal losses).
  • Design flow rate: Low flux and stratification.
  • Heat exchanger: efficiency.
  • Pipes: length, diameter and insulation.
  • Storage: volume and stratification.
  • Control: differential temperature, radiation, variable flow, etc.
  • Operation and assurances: expansion, clearers, safety valve, etc.
  • Design criteria.

Boletín Eléctrico

DHW heating with solar energy

In shared-user facilities, DHW production Solar will preferably be centralized, that is a unique system for capturing, sharing and solar accumulation.
In DHW production facilities, it means that the accumulation of water heated by the solar system will be connected to the cold water inlet of the installation. The water preheated by the solar system will move then, according to consumption, the conventional heating system (DHW heated boiler modulating instantaneous water heater, electric water heater, etc.) occurs.

In this type of scheme there is a first tank where water enters the system network directly and is heated by the solar system. The boiler heated tank is placed in series, and its input the output of the solar tank. For installations with consumption of 1000-3000 l / day, the scheme is usually solved by interaccumulators for both the solar system and the conventional. In systems with higher consumption of 5.000 l / day, solar accumulation is solved, usually with accumulators and external plate exchanger. For higher consumption it is often interesting to perform solar accumulation in closed circuit through two plate heat exchangers.
Thus, it significantly saves the initial investment in solar accumulation, to be able to use carbon steel tanks uncoated.

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