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Duct Work Connection Access (SVP)
To allow for the streamline tie-in of the SVP collector to the HVAC system, provide direct
access from the potential collector location on the south wall of the building to the outside air
(OA) intake of the air-handling unit. There should be a knockout in the OA duct to help facilitate
the quick installation of the SVP system. The knockout will reduce the extra costs that could be
accrued from installing extra ductwork, and also will ensure that the air does not cool
significantly before reaching the heating system. In addition, there should be a bypass damper to
allow the SVP collector to be bypassed while the building cooling system operates.
(Return to Checklist (SVP))
Additional HVAC Equipment (SVP)
The resistance of air through the SVP collector is larger than the resistance of air through an
outside air duct, thus increasing the pressure drop from the outside to the air-handling unit. This
increased pressure drop requires a larger fan to move the air. When specifying the size of fan for
the air-handling unit, be sure that the fan is large enough to accommodate the increased pressure
drop. In addition, specify that the HVAC control system has a sufficient number of control points
to operate the dampers required for the system.
(Return to Checklist (SVP))
Photovoltaic (PV) Systems
Additional requirements necessary for a building to be ready for a PV solar system are detailed
below.
Electrical Panel Location (PV)
Because the PV system needs to be connected to the electrical system of the building, the
electrical panel should be in a convenient location to connect to the PV array. The electrical
panel must have sufficiently large amperage rating to accommodate the PV energy as well as
grid energy. By Section 690 of the NEC, the sum of the ratings of over current protection devices
in all circuits supplying power to an electrical panel must not exceed 120% of the busbar rating.
When the electrical pane
l for
the building is selected, verify that the total energy coming into the building (proposed PV system size energy generation plus grid energy) does not exceed 120% of
the panel rating. There must also be space available in the electrical panel for a PV circuit
breaker. Near the electrical panel there should also be a convenient location for the inverter and
balance of system (BOS) components, with a sufficient amount of clearance in front of the
components to comply with NEC. Some of the electrical components can be located outside if
necessary, but exposure to heat and the elements will reduce the performance of the components
over time in some cases.
(Return to Checklist (PV))
Grid Inter-connection (PV)
The grid inter-connection rules are different in every state, and sometimes even vary by city.
Location-specific laws should be researched. The connection requirements vary depending on
what type of grid the building is connected to and what the serving utility is. The serving utility
representative should be contacted to determine what rules apply to the site. If the serving utility