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Stevens Institute Chiller
A natural gas engine driven chiller


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“Selecting American DG Energy’s On-Site Utility energy solution was one of the easiest executive decisions I’ve ever made.”

President and CEO
Nursing & Rehabilitation Facility

Natural Gas Chiller Cooling Systems

American DG Energy offers several natural gas chiller system options in the size range from 50 to 1,200 tons. Unlike conventional chiller systems, which use an electric motor to power a compressor driven chiller, a natural gas engine driven chiller uses an internal combustion engine to power a similar compressor in a refrigeration loop. This simple change in how the chiller cooling system is powered creates high efficiency along with heat recovery opportunities for the natural gas engine driven chiller system. Plus, it reduces demand on the grid which can help alleviate high summer electric costs, seasonal blackouts and electricity shortages, which are primarily caused by electric chillers.

While absorption chiller cooling systems also use natural gas, their efficiency and performance have been disappointing relative to engine driven chiller systems. Although a compressor driven chiller is a very efficient system for cooling a building, using a natural gas engine to drive the compressor makes it even more efficient – 2.5 times more efficient than the most efficient absorption chiller. As a result, a natural gas engine driven chiller cooling system provides greater comfort and savings.

Benefits of Engine Driven Chillers

There are several benefits to implementing natural gas engine driven chillers versus absorption chillers or electric chillers, including efficiency, system footprint and the use of natural gas fuel.

The primary benefit of a natural gas engine driven chiller is its high efficiency. As an example, a 200 ton system has a COP of 2.6, which is significantly more efficient than most absorption and electric based chillers on the market. And, certainly is much more efficient than your current system.

A natural gas engine driven chiller cooling system provides superior efficiency due to its the heat recovery capability. The heat from the engine which powers the compressor can be captured through a heat recovery system and then utilized within the building for various applications. The recovered heat can be used to heat domestic hot water, laundry hot water or to provide heat for swimming pools and spas.

Taking advantage of the heat recovery capability of a natural gas engine driven chiller provides significant fuel efficiency resulting in lower energy costs, reduced operating costs and reduced carbon emissions. Additional benefits, if converting from an electric chiller, include avoidance of on-peak electric demand charges and time of day rates.

Another benefit of a natural gas engine driven chiller is its compact size. An engine driven chiller is smaller than your absorption system and has the same footprint as your electric chiller. Replacing your existing system won’t require additional square footage.

In addition, a natural gas chiller cooling system can continue to operate during blackouts and brownouts throughout an emergency. Loss of power will not prevent the natural gas chiller from running. Though you still require some electricity to run pumps and fans, the amount of back-up power required is dramatically less than with other cooling systems.

Finally, our natural gas chiller cooling systems can also be modified to supply ice for rinks or process applications.

Chiller System Installation

Chiller system installation costs are not insignificant. Once the system is in place, the property owner is responsible for its operation and maintenance, requiring either internal man-hours or a third party service contract. For businesses with limited budgets and competing capital improvement projects, obtaining the cash or financing for a turnkey installation of a natural gas chiller cooling system can be difficult. In most cases an On-Site Utility is the best option.

Chiller System Candidates

The following qualifying criteria can help determine whether or not your property is a good candidate for a chiller system. bullets:

  • The property has more than 120 beds, rooms or units
  • Natural or propane gas is available on site
  • Cooling is supplied from a central chilled plant greater than 50 tons
  • The average electric rate from all suppliers is greater than $0.10 per kWh