NexRev Inc: DrivePak HVAC Efficiency Retrofit | NexRev, Inc.
“A simple solution to save energy and extend the useful life of existing HVAC systems. Solid examples show real world results for a number of clients.”
--Energy Manager Today Awards judge
DrivePak is an energy-saving upgrade for existing packaged rooftop air conditioning units. DrivePak brings variable speed technology to standard RTU and blower motors in the 3-5 horsepower range. Using preset speeds – without considering the actual air delivery of an existing piece of equipment – can result in unsafe airflows and potential unit damage. By matching the supply fan speed to run only as fast as the actual load requires, the reduction in energy consumption is automatic, and the savings impact of reduced motor speed is exponential, according to NexRev.
Equipment added consists of two components – a VFD and interface board. Existing controls remain in control of the heating and cooling. It is a conversion of a constant (full) speed motor to multiple-speed operation. No software or microprocessor programming or maintenance. An operational check of each unit is performed prior to installation. The method of implementation–utilizing test and balancing methods and specific set points for each individual unit–allows the unit to be commissioned at safe air flows. NexRev provides a compressor and heat exchanger warranty on units ten years old and newer that pass our minimum operating standards.
Total fan energy is typically reduced by over 70%, total unit energy usage by up to 50%, with project simple payback of 2 years or less. Additionally, the latent cooling capacity of the unit is increased, improving dehumidification and resulting in lower humidity levels in the space for improved occupant comfort. Reduced maintenance is also achieved, as DrivePak creates a “soft start” of the blower motor, reducing stress on belts, pulleys, shafts and bearings. Air filters see a lower total volume of air, extending their life, NexRev says.
NexRev cites numerous successes, including: More than 5,500 Cinemark Theatres’ RTUs in 300+ locations have been upgraded with DrivePak meeting Cinemark’s target of a 10-15% total energy reduction across the board; IRR for this investment sits at 40%; DrivePak is installed on 1,330 JC Penney RTUs on 131 standalone stores throughout the US, with savings results over 19 months showing a 14% reduction in overall building energy consumption in KWH translating to over $3.6M in annualized savings.
One judge was impressed by the product’s ease of installation, transportability, and wide market applicability.