Components of a typical solar hot water system include:

  • Solar Collector
  • Controller
  • Drainback Tank
  • Heat Exchanger
  • Solar Fluid
  • Heat Storage Tank
  • Water Pumps
  • Solar District Heating is now a reality in many parts of Europe Solar District Heating is now a reality in many parts of Europe
  • Solar heating panels are easy to install and provide cost-free solar heat from sunlight! Solar heating panels are easy to install and provide cost-free solar heat from sunlight!
  • Payback is quick and there are many government incentives Payback is quick and there are many government incentives
  • The principle is simple, reliable and proven The principle is simple, reliable and proven
  • Solar hot water preserves the environment Solar hot water preserves the environment
    

What Equipment Is Needed?

A solar hot water system is added to your existing boiler water heating system. It is typically used to preheat the cold waters flowing into the buildings normal not water tank.

This makes it ideal for retrofitting into existing buildings. There are only a few components that are needed:

Solar Collector These sit on the roof, typically on a steel structure supported by the parapets. It is worth noting that the tubes themselves hold no water, but merely conduct heat, making the panels light enough to be supported in almost all applications.
Controller This the the brains of the system. The controller decides when to turn pumps and valves on and off to collect heat from the sun. It is worth noting that in todays world, there are typically several levels of computer control, from the low-level controller, to a monitoring and HMI (human machine interface) and SCADA (supervisory control and data acquistion) system.
Drainback Resevoir This holds the solar fluid when the system is turned off. That way it won't boil inside the tubes
Heat Exchanger This transfers the heat from the panels on the roof or the heat storage tank to the buildings existing hot water system
Solar Fluid This is fluid that circulates inside the collectors and heat exchangers to transfer heat from the rooftop to the building. It is typically a mixture of propylene glycol (a non-poisonous anti-freeze) and water
Heat Storage Tank This tank holds a large amount of water (thousands of gallons) to store heat collected from sunlight during the day and release it at night to the building

A solar hot water system works by circulating the solar fluid between the collectors on the roof and the basement. In the basement, the heat from the solar fluid heats the cold water supply line to the building's boiler.

On a sunny day, when there is excess heat, the surplus is used to heat the fluid in the heat storage tank. That way, heat is available not just during the day, but at night as well. Heat can then be drawn off the storage tank to provide heat for showers, dishwashing and laundry at any time.