Main Street Lofts
Main Street Cupertino Lofts is part of a newly created, mixed-use neighborhood in Silicon Valley known as Main Street Cupertino. Construction of the Loft residence building occurred during Phase 2 of the development’s buildout. The property includes a two-level, below-grade, 92,000 square foot garage. NES commissioned its system in February 2018.
The Savings Opportunity
The Lofts garage is ventilated by two exhaust fan-motors possessing a combined 47.5 horsepower. With no means of control in place and running 24/7, they would consume slightly more than 333,200-kilowatt hours (kWh) per year, with a correlating peak kilowatt (kW) demand greater than 38 kW. The property’s utility rate is $0.205/kWh, so after factoring for fan runtimes and total HP, the annual cost to ventilate the garage (with no means of control) amounts to more than $68,000.
The NES Solution
NES deployed its Digital TR Series system in the Lofts garage. 23 BACnet-communicating, carbon monoxide (CO) sensors mounted throughout the garage provide instantaneous feedback to the NES controller, which then relays speed commands via Danfoss VLT® variable frequency drives (VFDs) to the two exhaust-fan motors, increasing and decreasing motor speeds based on CO concentrations at a given time.
Baseline energy consumption cut by 324,000 kWh, providing a recurring cost savings > $66,000
NES garage DCV system is limiting the fan motors’ combined kWh consumption to just 9,200 kWh/year. As a result, property management’s energy bill for ventilating the Main Street Cupertino Lofts garage is reduced from $68,300 a year (or $5,700 a month) to just $1,900 per year, i.e., $150 a month. "We couldn’t be more pleased with the results,” notes Mike Rohde, General Manager of Main Street Cupertino.