Electrical Edge, Inc
Solar and Electrical Contractor (NJ and PA)
The following is a list of questions for you to consider when choosing a Photovoltaic (PV) Installer.
Below is a cost break down that shows how much it costs for the Electrical Contractor to install a 5 kW and 10 kW residential PV system on a roof with a tilt of less than 25 degrees. Following the cost break down is a analysis of the Electrical Contractor’s profit margin depending on the price charged to the customer.
Cost break down.
Cost per Watt 10 kW PV system
$ 2.100 PV Modules
$ 0.250 Electrical Materials and wiring
$ 0.350 Racking
$ 0.650 Inverter
$ 0.070 Shipment
$ 0.450 Installation
$ 0.006 Transportation
$ 0.006 Design and Drawing ($600.00)
$ 0.006 License & Permit
$ 0.006 Shade analysis
$ 0.006 Incentive Application / Interconnection Paperwork
$ 0.008 Township Fee
$ 0.010 Structural Analysis
$ 0.003 Inspection
$ 4.019 Electrical Contractor’s Total Cost Per Watt
Profitability Analysis
| Profitability Analysis | |
| Price charged to the customer | Profit |
| $ 4.25 | 6% |
| $ 4.50 | 12% |
| $ 4.75 | 18% |
| $ 5.00 | 24% |
| $ 5.25 | 31% |
| $ 5.50 | 37% |
| $ 5.75 | 43% |
| $6.00 | 49% |
A photovoltaic system is an electrical system:
· Governed by the National Electrical Code,
· Installed by an Electrical Contractor,
· Inspected by an Electrical Inspector.
If your installer is not an Electrical Contractor, he will hire an Electrical Contractor to perform the installation. In this case, you will pay more than necessary.
On a 10 kW system, paying $1.00-$2.00 extra dollars per watt will cost you an additional $10,000.00 - $20,000.00 out of your pocket.
Reasons to ask this question:
Reason 1.There is often some sort of shade present on a roof. It could be an afternoon tree shade, shade from the plumbing vent, or shade from overlapping roof elements. Even a little shade dramatically decreases the performance of a system. There are ways to arrange panels on a roof to soften a negative shade effect. The person who performs the shade analysis on a roof can make a more informed decision than one who has not seen the roof. The person who performs the shade analysis should also be knowledgeable in system design.
Reason 2.Without being on the roof and not knowing exactly how wires and conduits will be run, a person can make mistakes when designing the system and making drawings for the installation crew. Will the conduits with wires be mounted directly on the roof, installed 3” off the roof, or go through the attic? Will the conduits and wiring be exposed to the sun or shaded by panels? How many wires will be run inside each conduit? One needs to know the answers to these questions in order to derate and size wiring properly. If wires are not sized properly, wire insulation can fail on a hot summer day, and your system will stop functioning. Wires sized improperly can also result in fire and electrocution hazards. The customer needs to understand the risk of using a PV system designed by someone who has never seen his roof.
Every article in the National Electrical Code was added as a result of a hazardous occurrence. A PV system is safe when installed properly. There are “installers” around who have never read the Code.
Why take a chance?