Solar air conditioners - how solar can cool your home

house with solar panels on roof

Summer’s nearly here, making now the best time for home and business owners to start thinking about how they’re planning to keep their spaces cool in the hot summer sun, cost-effectively. Solar power has evolved to the point where people can harness the sun to power low-cost and environmentally-friendly air conditioning.

Solar air conditioning is a viable option to consider whether you’re looking to replace your existing air conditioning units or adding them to a building for the first time. After all, the Department of Energy says that high-efficiency air conditioners can reduce air conditioning bills by up to 50%. Since heating and cooling comprise about a third of a home’s energy bills, this solar-powered alternative leads to a lot of savings.

Image source: Department of Energy

Harnessing solar power to cool the home

Solar power can help to cool homes and buildings in three primary ways. The most common is through the use of photovoltaics (PV). In these systems, solar panels collect solar energy and use it to power an air conditioning unit or central heating and cooling system (also known as an HVAC system). 

The other two types of solar powered air conditioning systems are passive systems and solar thermal systems. Passive systems incorporate building design, insulation – even landscaping. Solar thermal systems use the sun’s thermal energy to provide cooling through heat pumps.

What is typical of most – if not all solar air conditioners – are high seasonal energy efficiency ratio (SEER) numbers. What this means is, once installed, they are highly efficient and will help bring down the cooling costs on electric bills in a big way.

A look at solar hybrid air conditioning

Solar hybrid air conditioners are usually electronic air conditioners that are powered by PV solar panels. These systems can be designed to work alone or as part of a home’s solar energy system. 

For instance, Lennox’s SunSource systems are built to provide power to an air conditioner or heat pump first, then bringing power to a home or building directly, thereby providing excess electricity to the electric grid.

Other air conditioning options exist, as well. Many solar hybrid air conditioning units being advertised are mini-splits. These are systems fashioned with a compressor on the outside and are connected with a blower or air handler on the inside that provides cooling for rooms. Some systems can accommodate multiple air handlers, essentially allowing users to cool multiple rooms in a building, without cooling the entire building.

The PV systems powering mini-splits can be grid-tied or altered for remote applications, such as in a mountain cabin with no electric grid access. PV systems like these also have the ability to come equipped with energy storage, allowing for operation at night or when sunlight isn’t available.

There are kits that exist for solar hybrid air conditioning systems, as well. Solar installers can help size a system appropriately and provide professional solar installation services. Not only that, they can provide long-term warranties and help maximize the incentives for solar air conditioners.

Exploring passive solar cooling systems

Passive systems are the most innocuous form of solar cooling. Proper insulation, siting, and architectural design can go a long way in reducing a building’s energy use for heating, cooling – even lighting. 

So, too can landscaping. Using deciduous trees such as maples or elms near a building can provide shade during hot months to help reduce some cooling needs. 

Similarly, insulation can help maintain the temperature in a building, keeping it stable throughout the year. However, it’s easier to properly insulate a new building than retrofit insulation in an existing building. 

solar irradiance heating solar panelsImage source: Science Direct

Understanding solar thermal air conditioning systems

Unlike PV systems, solar thermal AC uses the sun’s thermal energy, rather than electricity, to provide cooling through a heat pump.

In solar AC systems that use absorption, a refrigerant is used (as it is with a regular air conditioner). However, instead of using electricity to power the compression and heating of the refrigerant, solar thermal panels are used to heat the medium up. It’s then evaporated and pumped through coils to absorb heat and moisture, just as a normal air conditioner does.

Historically, solar thermal air conditioners were meant for larger applications, namely commercial buildings. But in recent years, residential solar heat pumps and thermal systems have been developed.

Solar thermal air conditioners still do require electricity in order to power the pumps and fans that move the air and refrigerants. Because they use solar energy to heat the refrigerants, however, it takes much less electricity to move them than the power that a traditional air conditioning unit demands.

Keeping cool for the summer with solar

All of these eco-friendly options help reduce electric costs, making going solar an undisputed way to start saving on electric bills. When coupled with solar air conditioning, it’s simply a cool way to green your summer chilling.

Author: Chris Meehan

Learn more at: https://www.solarreviews.com/blog/how-solar-power-can-cool-your-home