Solar Water Heating


  • Solar Power is Inexhaustible
    • Solar heating is a very simple concept in which a solar boiler gets hot from solar rays and has water pipes running through it. The heat is the transferred to the pipes, which in turn heat up the water or air
    • There are low-, medium-, and high-temperature collectors. Low-temperature boilers are generally used for applications like swimming pools. Medium-temperature systems are generally used to heat water or air for residential and commercial use. High-temperature boilers are made by concentrating the sunlight using mirrors or lenses and are generally used for electricity generation

Green Energy:

  •  “Free Energy”
    • Hot water is the second highest energy costs in a typical household, and in some cases, especially in colder climates, it could be the highest expenditure
    • The heat collected using boilers isn’t exactly free as it requires electricity for a pump to operate, but the amount of electricity it requires is miniscule in comparison to the energy required to heat water using conventional methods
    • Most systems also include a PV cell which could power the pump for most of the day
  • Environmentally friendly
    • Solar boilers are very environmentally friendly as the use of electricity or gas will be dramatically lowered. They do not produce any emissions and the savings in electricity or gas also mean they help lower households overall emissions

Canadian Perspective:

  • Energy provided
    • Since 2007 there have been an estimated 544,000 m2 of solar collectors operating in Canada
    • Most of these are collectors for pool heating (~71%) and most of the rest are used for air heating of commercial buildings (26%)
    • These systems displace an estimated 38,000 tonnes of CO2 annually

Technology Advancement:

  • Solar thermal heating has been around since 1896 when it was invented in United States. Since then there have been many advances which have led to its wide use
  • By 1909 William Bailey invented the first thermosyphon system which placed the tank on the roof and collector beneath. By the 1930s this led to widespread use of solar water heating systems in California and Florida
  • The biggest boom to the solar heating advancements came in the 1970s when the price of oil started to rise and when the space program decided to use solar power. This was also the time when initial connections between fossil fuel use and climate change were being made
  • Improvements to the system came from use and storage in milder climates, and the use of antifreeze
  • The larger high-temperature systems have seen the largest advancements as they result in commercially usable electricity. Countries across the world have started implementing systems which concentrate sunlight onto a boiler, creating steam to be used with generators. Spain implemented Europe’s first commercial solar tower, which uses molten salt storage systems to ensure power is available 24 hours a day