Page 198 - Solar Power in Building Design The Engineer's Complete Design Resource

168 ENERGY CONSERVATION

alternating current is converted into direct current that provides energy for lighting
and storage.
■ In the event of solar and electrical service power loss, the direct current stored in
the battery banks is routed to the lighting control or machinery drives.

Nextek Power Systems recently designed and installed their high-efficiency renew-
able energy lighting system at a distribution center in Rochester, New York. The
project, which is a LEED-rated gold facility, is equipped with a lighting system that
utilizes dc fluorescent ballasts, roof-integrated solar panels, occupancy sensors, and
daylight sensors for the highest possible efficiency. The building was designed by
William McDonough and Partners of Charlottesville, Virginia.
2
2
The facility has 6600 ft of office space and 33,000 ft of warehouse space. The
warehouse roof is equipped with skylights and 21 kW of amorphous panels by Solar
Integrated Technologies that are bonded to the roof material. A canopy in the office area
is also equipped with 2.1 kW of Sharp photovoltaic solar panels. Figure 6.12 depicts
wiring diagram for NPS1000 module a direct PV output dc wiring with battery backup.

Solar PV (Optional)
NPS Power Unit
Wiring Detail
PV PV PV

AC Electric NEXTEK
Service Panel
POWER
UNIT IMPORTANT
NPS1000 Metal 2900 micF, capacitor Nextek
Metal Box
208 to Box part: NA 2900 must be
277 V AC Ground + Metal included in the circuit.
Box
AC Line
AWG #12 + + + + + -
Fuse
Cable appropriate 12-V 12-V
12-V
12-V
Circuit AWG #12 Group Group to load Group Group
Metal Cable 24/27 24/27 24/27 24/27
Breakers Box Battery Battery Battery Battery
AWG #12 Battery (Optional)
Cable or
larger

S S
T8, 48-in
Fluorescent Fixtures
Figure 6.12 Wiring diagram for NPS1000 module a direct PV output dc wiring
with battery backup. Photo courtesy of Nextek Power Systems.