Heating, ventilating, and air conditioning – HVAC — is a critical component of any modern structure, from a single-story ranch house to the tallest skyscraper. Typically, any power that an HVAC system needs to function is drawn directly from the electric grid, the same as other home systems. Only in recent years renewable energy has raised questions about the very need for outside power in the home.
Solar power has been a big part of a change that is sweeping the world, as millions of homes and businesses turn to alternative resources to supply at least a hefty percentage of their power needs. Solar is most famous for creating electricity and heating water. Yet its footprint in the HVAC sector is bigger than you might think.
Passive Solar
While the effect may be subtle, it is impossible to ignore the influence that passive solar design has on a structure’s HVAC system. A smart home design will harness the sun for heat during cold months and minimize that heat gain during the summer, both of which lessen the workload for the HVAC unit. Passive solar air heaters can also be used to heat rooms and fit right into a window or wall.
Heating
Most HVAC systems are active electric or gas systems, but there are active solar space heating systems out there as well which supplement or even eradicate the need for outside sources of power. Solar heating systems are solar thermal systems by nature and themselves may be active or passive and liquid or air-based. The high initial cost of solar heaters is really the only barrier to more widespread use. Given time, every system will eventually save money by reducing or erasing high and rising monthly power bills.
Air Conditioning
Space cooling is another application for which solar power shows promise. The idea may seem strange — using solar heat to cool a home — but it is really no different from other systems which use electricity or combustible gas. Solar space cooling is more complex than other solar thermal systems but is a viable air conditioning option nonetheless. Technology and innovation may make it even more appealing in the near future.
Ventilating
Any active or passive solar HVAC system will have ventilating components so that warm or cool air may get in while allowing unwanted air to escape. This is common for all types of HVAC systems and solar systems are unlikely to do it any differently than conventional ones. Usually pumps or fans are utilized to force air from the HVAC unit into the home.
Solar powered ventilation need not be a part of a solar HVAC system only. Solar attic fans, for one, help ventilate the house without any need for wiring. Again easing those monthly utility bills while serving a key function in the HVAC system. And when it comes to solar fans, the attic is not the limit.
Photo credit: Evan Esposito Solar