Serious ROI

Energy efficiency and sustainable retrofits typically reduce energy consumption by 10-20%. However, by taking an integrated, whole-building design approach, the team was able to predict savings of almost 40%. Energy analysis (eQuest energy modeling) predicts an ongoing annual energy savings from the super-insulated windows alone of more than $412,000.

Whole-Building Energy Efficiency

With an initial estimated project cost of $20 million, additional savings and redirection of expenditures originally planned in the building's upgrade program, plus additional alternative spending in tenant installations, the Empire State Building will save $4.4 million in annual energy savings costs, reduce its energy consumption by close to 38%, repay its net extra cost in about three years, and cut its overall carbon output. Based on the phasing-in of the recommended projects, it is estimated that over 100,000 metric tons of carbon will be saved over the next 15 years. This is equivalent to the annual emissions of 17,500 cars (source: SolveClimate.com) or the use of approximately 11 million gallons of gasoline (source: RMI).

Peak Electrical Usage

Electricity costs in New York City fluctuate depending on demand, and are highest during peak demand hours in summer when everyone is using their A/C. Under the proposed retrofit plan, peak electrical usage will also be reduced by 3.5 megawatts, from its current peak and capacity of 9.6 megawatts to just over 6 megawatts. The super-insulated windows can take credit for a large proportion of these savings because SeriousGlass will cut inbound heat from direct sunlight by more than half. By reducing electricity consumption during these peak hours the Empire State Building can avoid purchasing the most expensive electricity of the year.

Enhanced Tenant Environment and Comfort

In addition to reducing energy and CO2 emissions, the super-insulated windows play a critical role in providing increased occupant comfort:

• Improved thermal comfort – keeping cool during the summer and warm during the winter
• 99% blockage of UV rays, keeping furniture and artwork from fading and enhancing human health
• Warmer glass temperature in winter months and cooler glass temperature in summer months will make occupants more comfortable, particularly those working at the perimeter of the building near windows. In addition, the super-insulated windows are expected to result in higher thermostat set points in the summer and lower set points in the winter, reducing overall heating and cooling demand, particularly during peak energy hours.