Radiant heating, cooling systems paired with geothermal boost efficiency (video)

A recent study by the New Buildings Institute found nearly half of the zero-energy buildings in the United States incorporate radiant systems to meet their energy goals. The study also notes that these systems are often integrated with ground-sourced heat pumps to achieve zero energy as part of a cost-effective package.

Hydronic radiant heating and cooling systems combined with downsized air-handling systems can reduce HVAC energy consumption and initial investment costs while increasing thermal comfort in commercial buildings. When further integrated with a renewable energy source, such as the REHAU RAUGEO ground loop heat exchange system, REHAU radiant heating and cooling systems make a significant contribution toward high-performance and net-zero commercial building.

The company featured the heating solution at the recent AHR 2016 in Orlando.

Radiant heating and cooling systems work by circulating fluid through a network of RAUPEX O₂ Barrier crosslinked polyethylene (PEXa) pipes placed in the floors, walls or ceilings. When the circulating fluid is warm, heat is gently radiated from the panel, warming the surfaces, objects and occupants in the room and eliminating drafts and hot spots. When cooled fluid is being circulated through the pipes embedded in the building structure, radiant cooling evenly absorbs heat energy, cooling the space to a comfortable temperature.

Used in combination with a downsized air-handling system, a hydronic radiant heating and cooling system can condition a space very efficiently. By reducing the load on the air-handling system with more efficient hydronic energy transfer, radiant systems can not only reduce energy costs by 30 percent or more, but can also lower initial investment costs by allowing the air-handling system to be downsized.

In addition to saving energy, radiant heating and cooling systems that use moderate water temperatures pave the way for integrating a water-to-water geothermal heat pump system for maximum efficiency. Geothermal systems exchange energy from the earth to heat and cool at a fraction of the operating costs of traditional HVAC. According to the International Ground Source Heat Pump Association, ground source heat pumps can reduce energy consumption by up to 50 percent when compared to conventional systems.

The REHAU RAUGEO ground loop heat exchange system provides numerous advantages over traditional geothermal systems. The RAUGEO crosslinked polyethylene (PEXa) piping system offers superior flexibility and abrasion resistance, while pre-formed double U-bends require up to 30 percent less borehole footage than a single HDPE U-bend. RAUGEO ground loops usually begin and end at a balancing manifold that, unlike the typical reverse-return header, allows each ground loop to be individually controlled for system optimization.