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Solar Space Heating


Solar Ontario has designed & installed solar space heating systems. The systems work and people are happy with them. However, we want people to know that solar space heating can only supply a portion (typically a small portion) of the space heating load. (Solar heating systems require full-size backup heating systems.) Solar space heating systems are not inexpensive and the payback can be very long.

Solar Ontario favours the use of PV-based solar space heating systems over anti-freeze- based or air-based solar heating systems. Many of the components used in solar space heating applications are also found in solar domestic water heating systems.

There are air heating solar collectors designed to deliver heat directly into a living space when the sun is shining. These products do not (and cannot) incorporate any form of heat storage - so when the sun goes  down, they  can no longer deliver heat. Most of these systems will deliver less than $20-$25 dollars worth of (natural gas) heat a year per 4' x 8' collector. (Based upon natural gas costs in Ontario September 2017.) 

This fact flies in the face of all of the claims made by the manufacturers of these products. Most of these wall-mounted products claim energy savings of $500+ dollars a year per 4' x 8' heater. These claims are utter nonsense - even under ideal circumstances. The "$500" figure comes from the product needing to have a 5 year or less payback if it's going to sell. The reality is a good quality window of the same size will capture as much heat, cost about the same to install and allow you to see outside!

30+ years ago, solar air collectors were built with rock heat-storage systems. There were many issues with moulds and heat leakage that caused the concept to be abandoned. The cost of running the electric fans used for moving the heat around also tended to cancel out a large part of the savings.

Water or anti-freeze based solar space heating systems are often incorporated into radiant floor heating systems, but these systems can become quite complex. The new PV powered solar heating inverter from CyboEnergy can be used to heat water, air or a electrical radiant-floor directly. Also it has the potential to be easily repurposed when the space heating load is met. This product will radically change how solar space heating is done!

For more information on the CyboInverter for solar heating click here.

We have prepared a  Solar Space Heating FAQ, to view it please click here.