Energy-Efficient Solar HVAC Units
iAIRE’s patented Solar HVAC units are the most efficient package Roof Top units (RTUs) and split systems in the world. iAIRE’s Solar HVAC units harness the sun’s energy to create an HVAC system that can be up to twice as efficient as any other units currently in the market. This technology can be applied to both residential and commercial HVAC equipment.
How Solar HVAC Works
To help describe how the iAIRE patented system works, iAIRE will give a brief explanation of how a standard HVAC system works and then discuss how the iAIRE Solar HVAC system works.
In an HVAC system temperature and pressure are directly correlated. Whenever there is an increase in pressure in the HVAC system, there is a corresponding increase in temperature. If there is a decrease in pressure, there is a decrease in temperature.
There is a compressor in the system that pressurizes the refrigerant to move it through the system and heat the refrigerant. This refrigerant then travels through the condenser (the unit that is normally sitting outside your house) where the hot temperature is emitted to the atmosphere to help cool the refrigerant down. The refrigerant is then piped over to the evaporator coil. This coil is located in the Air Handling Unit (AHU) that is normally inside your house. Warm air from the house is passed across the cool coil. This cools down the air and in many cases also removes moisture. The warmer refrigerant is then returned back to the compressor and the cycle is repeated over and over again.
How iAIRE Solar HVAC Systems Are Different
iAIRE is utilizing Solar HVAC in a way that has not been utilized before in HVAC systems. A solar panel is installed on the HVAC unit. The solar panel can be installed either between the compressor and the condenser, or in between the condenser and the evaporator. In lieu of generating electricity with the solar panel, the solar panel on the iAIRE Solar HVAC is used to generate heat. A solar panel is installed on the HVAC condenser unit.
The compressor in the HVAC system has a Variable Frequency Drive (VFD) installed on the compressor. The Solar HVAC unit utilizes the sun’s energy to put heat into the refrigerant. Putting the heat into the refrigerant replaces a portion of the energy the compressor would normally put into the system from the electrical system in the building.
There are sensors in the condenser unit that sense pressure or temperature and provide feedback to the HVAC controls indicating how the system is operating. As the solar panel adds more heat to the system, the VFD will back down the speed of the compressor to keep the system running at its normal operating pressure. As the compressor runs slower, it is utilizing less electricity to operate. The compressor is normally the item in the HVAC system that uses the most energy. In many cases, the compressor will utilize less than ½ the energy that is normally consumed to operate an HVAC system.
iAIRE’s Solar HVAC unit also provides an additional energy saving on top of the reduced electrical load of the compressor. Because there is a VFD installed on the compressor, when the compressor is first turned on, it will have what is called a “soft” start-up. In lieu of the compressor turning on at full speed and having a momentary inrush of current, the compressor will speed up slowly to speed. This large reduction in the inrush of current reduces the utility company demand (maximum current draw of the system) and helps additionally save energy and utility dollars.
iAIRE Solar HVAC Results
Part of the amazing results that iAIRE’s Solar HVAC achieve are because of the solar film that is used in iAIRE was developed by the National Renewable Energy Lab and is much more efficient than the film used in standard solar panels. This film does not need direct sunlight to produce heat. It utilizes all the spectrums of light to produced by the sun to generate heat. iAIRE’s solar panel produces the most energy in direct sunlight. However, as long as the sun comes up (even if it is a cloudy day) the solar panel will be providing some heat to the system since this film operates even with ambient light. This is different than most standard solar panels that need direct sunlight to operate.
iAIRE’s 5-ton solar panel is about the same physical size as a single solar panel that is normally installed on a house roof. A solar panel on a house is providing approximately 1.34 amps when it is sunny outside. iAIRE’s solar panel does not provide electricity. It reduces the amount of electricity consumed by the compressor. On the same sunny day that a standard solar panel produces 1.34 amps, the iAIRE solar panel is reducing almost 15 amps of draw on the compressor. To get the same result, a homeowner would have to install 10+ solar panels on their rooftop. This is an amazing amount of additional energy provided by the same size solar panel.
IS SOLAR HVAC COST EFFECTIVE?
Solar HVAC has a substantial on-going utility savings over conventional HVAC equipment. This savings usually amounts to 40 – 50% of the energy that is used by the HVAC equipment, along with the fact that since the Solar HVAC has an inverter on the compressor, the in-rush current is low and if the utility in the area has peak demand electrical charges, these are eliminated or minimized by Solar HVAC.
In addition to the Solar HVAC utility savings, there are many incentives that federal, state, and local governments are providing for solar projects. There are also many utility incentives for these projects. For a complete list of these programs, go to https://www.dsireusa.org/. This website was created by NC State University and has Federal, State, local and power company provided incentives for every state around the country.
The federal government currently offers a federal tax credit of 26% of the installed cost of a solar system. Current legislation is moving through Congress that would move this up to 30% on all solar panels and an additional 10% for American made Solar Panels.
Plus, an additional 20% for Solar Projects on low-income housing. Since iAIRE makes our solar panels in the US, iAIRE would be eligible for a 40% Federal tax credit on normal jobs and 60% on low-income housing if this legislation gets through Congress. iAIRE has written a document to show both businesses and homeowners how to obtain this tax credit.
The tax code also allows for an accelerated depreciation schedule on solar projects. At the current rebate rate of 26%, a business could depreciate 87% of the cost of the equipment and installation the first year. Also, most states are not charging sales tax on solar projects.
The up-front cost for Solar HVAC is more than conventional equipment. Because of this, most people believe there is still a long payback period to pay for the additional cost of utilizing Solar HVAC over conventional equipment. Below iAIRE will show a couple of examples of the use of Solar HVAC compared to conventional equipment to show that the payback on projects can be seen as rapidly as the first year.
This chart is an example of a 5-ton packaged roof top unit replacement on a store in Orlando Fl.
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This analysis assumes a 26% Federal Tax credit, no sales tax, and a $0.13/kwh cost for power. The numbers show that this customer would experience a first-year savings of $524.66 and then the ongoing savings from installing Solar HVAC will save this customer $16,065.92 over the first 7 years of the HVAC equipment’s life.
This chart is an example of a large commercial new construction job where the customer chose Solar HVAC over conventional equipment in Columbus, IN.
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This analysis assumes a 26% Federal Tax credit, no sales tax, and a $0.12/kwh cost for power. The numbers show that this customer would experience a first-year savings of $286,400.34 and then the ongoing savings from installing Solar HVAC would save this customer $424,517.53 over the first 7 years of the HVAC equipment’s life.
As shown above, Solar HVAC can have a payback as quickly as the first year. In almost all cases, the payback on Solar HVAC is 3 years or less when installed on new equipment. Please contact iAIRE for more information or to discuss your specific project or questions.
Solar HVAC Documents
Model “C” Condenser Only Units:
Model “Z” ultraRes Units: