1500 Walnut Street in Philadelphia is a 22-story, 275,210 SF professional office building with a 160-car parking garage. The original 22-story tower of the property was constructed in 1926 and a second 20-story tower and 4-story parking garage was added in 1965. The two towers are fully connected with seamless floor plans in the first through 20th floors.

Facing a failing HVAC system and declining tenant satisfaction, the building’s management team decided to install CALMAC’s IceBank® thermal energy storage tanks and two 300-ton chillers. The new tanks are assisting in saving 1500 Walnut Street $40,000 in energy costs per month during the warmer months and generating an additional $10,000 of revenue per year through utility incentive programs.

1500 Walnut PhiladelphiaSince the upgrades were installed three years ago, total annual savings are at about $200,000 per year plus greenhouse gases are estimated to have been reduced by 900 tons annually. The building has become a “virtual power plant,” preparing it for the smart grid for the same cost of the existing outdated system.

“The system we had in place was an energy hog that was affecting bottom-line revenue for the owner,” said Gene O’Donnell, the building manager at 1500 Walnut. “There was no question we needed a new system, but we also couldn’t burden the tenants while we installed it.”

The new thermal energy storage system, which was installed at the recommendation of Tozour Energy Services for the same cost of the existing outdated system, allows ice to be created at night, when power is less expensive and generated more efficiently. It is then used the next day to cool the building during peak demand hours, which has significantly reduced operating costs. The thermal energy storage tanks were also paired with Viridity Energy’s VP Power software to provide additional flexibility. With this upgrade to the building controls, CALMAC’s tanks are able to function as a part of a real-time demand response system that utilizes data from the utility company.

“Viridity Energy can forecast where prices due to congestion will be for the next day on an hour-by hour basis and provide a schedule to the building operator through the building automation system, which the ice system is tied into to make ice or burn ice,” said H.G. Chissell, vice president, NE region and strategic accounts at Viridity Energy. [pullquote]There was no question we needed a new system, but we also couldn’t burden the tenants while we installed it.

- Gene O’Donnell, Building Manager[/pullquote]“When they are using ice they are not using their chillers and their load drops. We can then make sure that the grid operator knows that this load is dropping during these hours and they don’t have to go to a power plant. The grid operator diverts the income or the money to the building.”

“1500 Walnut has turned into a ‘virtual power plant’,” said Mark MacCracken, CEO of CALMAC. “If the utility company can pay a building to reduce their load at a cheaper price than it costs them to generate the extra electricity, they would much rather do that. It becomes a win-win for the building and the utility company.”

When referring to the additional revenue O’Donnell added, “We don’t need one square foot of space in this building to make this money, and the tenants in this building see no change at all. We’re as happy as pigs in mud. The system works ”

CALMAC Manufacturing Corporation is transforming how energy is used at buildings to the time energy is used. Widely recognized for promoting peak energy conservation and energy cost savings CALMAC is a member of the U.S. Green Building Council (USGBC), the California Energy Storage Alliance (CESA), and the Texas Energy Storage Alliance (TESA). CALMAC is the manufacturer of IceBank® Energy Storage equipment, with over 4,000 Ice Storage installations worldwide. IceBank systems are a valuable component of the smart grid, enabling energy, including renewable wind energy that mainly blows at night, to be efficiently stored for use during periods of high demand.

About Tozour Energy Systems
Tozour Energy Systems is a full-service HVAC and building automation provider based in King of Prussia, Pa., and is a franchise of Trane, a business of Ingersoll Rand. The company provides customers with a diverse range of solutions including building automation, equipment services, energy conservation services, green building design, controls, parts, supplies and responsible technical support throughout Pennsylvania and New Jersey. Tozour Energy Systems is a member of the Delaware Valley Green Building Council. For more information, visit www.tozourenergysystems.com.

About Viridity Energy
Viridity Energy is paving the way for a new generation of demand response through its innovative demand-side management solutions. Viridity Energy provides large energy consumers with intelligent tools to reduce their energy spend by increasing energy supply cost savings and/or creating energy revenues through its unique and flexible VPower™ platform. VPower™ enables customers to reduce overall energy spend by dynamically managing energy load and integrating advanced energy technologies. Headquartered in Philadelphia, Pennsylvania, Viridity Energy was founded in 2008 by former executives of PJM Interconnection. For more information, visit: www.viridityenergy.com.