NEXTEK’S AIR HANDLING AND SOLAR POWER SYSTEM DELIVERS 40% ROI

OVERVIEW

In 2003 the settlement of a clean air lawsuit required the Virginia Electric Power Company to pay $2.1 million for air pollution mitigation projects in New York State. The $2.1 million was administered by the New York State Energy Research and Development Authority to install solar energy equipment on government-owned buildings in the state. In 2004 the Town of Hempstead, on Long Island, received $260,000 in funding to update their Town Hall with a new solar power system and DC microgrid.


SOLUTION

The Town of Hempstead commissioned Nextek Power to provide the first commercial-scale integration of a DC solar power system with an Allen-Bradley PowerFlex 700 series motor drive* in the Town Hall’s HVAC system.

Rather than switching the air handler off and on, the VFD allows the motor to be run at slower speeds when not needed. This avoids huge start-up inrush currents and helps the motor last longer.
These VFD’s typically require a rectifier between the AC input and the DC voltage-regulator. Nextek’s technology removes the need for a rectifier, creating a highly efficient system that can continue circulating air during a daytime power failure, even without batteries.

On the southern face of Hempstead’s Town Hall a 256-panel, 40-kilowatt solar energy system supports Allen-Bradley motor drives without any hardware modification. The power generated by the solar panel carries 2 motors (a 40hp and a 25hp) during the peak of the day, seamlessly changing the power source to grid-supplied Alternating Current (AC) as the sun goes down.


RESULTS

The Nextek Power Gateway connects locally generated power and grid power directly to electronic loads in the building. Nextek’s Direct Coupling Technology creates highly efficient, flexible, uninterruptable DC power networks in the building.