Benefits of energy management in green building.

Based upon our experiences in developing The Solaire, New York's first green residential tower, and commercial buildings on Long Island, Albanese Organization would like to discuss three precepts we feel to be true:

1) Green buildings can be competitively developed in urban and suburban markets; 2) Seeking the goal of energy efficiency can also contribute to creating healthier micro (interior) and macro (community) environments, and; 3) The resultant economic and health benefits enjoyed by all occupants (resident, commercial tenant, employee, student) will produce a positive return on the building owner's green investment, as well.

In developing The Solaire, located in Battery Park City (it was the Battery Park City Authority, under the leadership of Tim Carey, which initiated the challenge to develop sustainably in accordance with their Residential Environmental Guidelines), our goal was to provide living spaces of extraordinary comfort that promoted energy efficiency, while providing healthier residential experiences.

The degree to which this was achieved was recognized when The Solaire was honored as the first high-rise residential building to attain a LEED gold rating. LEED and other green models advance recommendations in five areas of design: energy efficiency; indoor environmental quality; resource & materials conservation; operations & maintenance; and water conservation.

While all of these are important, we will concentrate here on the impacts of the first--energy efficiency.

Certainly energy efficiency starts with a tight building envelope, with sealed joints, high levels of insulation and high performance windows. However, as was learned, tight buildings without properly designed ventilation and conditioning systems can lead to "sick buildings' and poor indoor air quality. This highlights the holistic character of green design and the interdependence of energy management, systems design and air quality.

To manage energy effectively it is necessary to understand not just how much energy is consumed, but what type, where and when. Key to answering these questions is the building management system (BMS), which measures where energy is being consumed. By monitoring occupancy, activity and air quality, the BMS can adjust the flow of energy to meet demand.

The system controls the variable speed motors, fans, occupancy sensors, automatic dimming devices and other controls that promote wise energy use. It maximizes motor efficiency, and prompts timely periodic maintenance and filter changes, thus increasing component useful life. Also, its diagnostic capabilities pinpoint any malfunction, thus enhancing staff efficiency and lowering maintenance cost. Therefore, managing energy also saves on other operating costs.

Energy management is aided by providing local controls that promote comfort in occupied areas, while automating efficiency measures in unoccupied areas. These features include programmable thermostats, occupancy sensors, automatic dimming controls and energy efficient lighting, appliances and office equipment. These reduce demand on HVAC equipment, while increasing occupant comfort, health and productivity.

In some settings energy management involves making the user aware of the cost and a beneficiary of the savings. In this context dedicated HVAC systems and sub-metering will reinforce the installed efficiency controls and benefits.

From a cost and environmental impact perspective, when and what type of energy is consumed can be as important as the absolute amount used (Kwh). Reducing peak demand (kilowatts or Kw during times of highest system demand) can minimize the utility's use of less efficient coal burning plants, lower fossil fuel consumption and improve macro air quality.

Two technologies we employ to achieve this are photovoltaic cells (PVs) and natural gas-fired micro turbines.

The former convert solar energy into electricity for use within the building.

By their nature, PVs are most effective in peak summer hours when energy demand is greatest and utility demand charges are highest. (Demand charges are applied to the entire months' energy use based upon the peak demand during any quarter hour period. Therefore "shaving" peak demand a little has great benefit.)

Micro turbines have the same goal of generating energy during the most expensive times by using a fuel that is not subject to time of day pricing. Moreover heat recovered from the micro turbine exhaust can be used productively, to heat the building's domestic hot water, for instance.

General heat recovery capabilities when linked to the ventilation-exhaust systems bring us full circle to our discussion of tight buildings needing good ventilation. While an efficient envelope eliminates inadvertent, unfiltered air infiltration, fresh air is still needed for a healthy environment. The benefit of heat recovery, which transfers heat from the air being exhausted to pre-heat fresh air being introduced, enables the rate of ventilation to be increased, since the energy is being "recovered" rather than lost. This results in a healthier, more productive indoor environment. (The heat recovery described should not be confused with mixing exhaust and fresh air. There is no mixing or deterioration of the fresh air).

Thus, striving for energy efficiency can also improve air quality, comfort and productivity.

Who benefits? Everybody: the resident (including dormitory students); the employee; the employer (through greater productivity, lower absenteeism and controlled energy costs); and the building owner (from higher rents, lower maintenance costs and enduring building value).

And when the building is owner-occupied, including institutional owners such as hospitals, public schools and universities, the benefits just compound.

The Albanese Organization is employing all of these energy management strategies (and others) in our second green residential tower, currently under construction at Battery Park City, and at a major commercial renovation taking place in Garden City.

While each set of energy management components should be designed for the specific building and use, a list of options might include the following:

* A highly insulated and sealed building envelope with a high performance window system, combined with ventilation systems equipped with energy recovery capabilities.

* A Building Management System (BMS) to monitor air quality, occupancy activity, system performance and manage controls to optimize energy efficiency

* HVAC systems that provide for dual fuel capabilities or natural gas to allow energy source selection to reflect market and pricing variables.

* High efficiency air filtration and seasonal humidity adjustment, with local controls to optimize comfort and apportion energy costs.

* Distributed or co-generation capacities, where feasible, so electricity can be produced on-site, with productive use of the heat from the generation to meet other energy needs, such as hot water heating.

* Photovoltaic cells either integrated into the facade or roof mounted to shave peak load and produce energy from a renewable, non-polluting source.

* Occupancy sensors in common spaces, such as hallways and stairwells, and in offices and conference rooms in commercial settings

* Energy efficient lighting in all areas, with timed dimming capabilities in public hallways.

* Programmable, digital thermostats with local controls and BMS monitoring and automatic setbacks based upon time or occupancy sensors.

* Energy Star fixtures, appliances; office equipment, with particular attention to computer screens and related equipment that a heat generators that place demand on HVAC systems.

RUSSELL C. ALBANESE,

PRESIDENT, ALBANESE ORGANIZATION