7.9 kW Solar Design and Installation

7.9 kW San Mateo, CA

There is a way to make solar so simple that you know you are getting the best solar array for your needs. SunWatts’ Solar Consulting and Design Service personalizes your solar array selection and eases the process of going solar. A recent Solar Design of a 7.9 kW Solar Array in San Mateo, CA, shows how valuable the Solar Consulting and Design service is, not only financially, but also for the peace of mind knowing that you made the best choice for your solar needs. The San Mateo project resulted in a beautiful solar installation in this home that met their personal home renewable energy needs.

The project began with a solar design with a review of the consumption history of the residence and any planned changes to energy consumption. It was determined that a 9kW PV solar array with up to 27 panels would meet 100% of the annual consumption needs to eliminate the power bills.

Next, the rooftop layout possibilities were considered. The roof has space for 24 standard-size panels of approximately 65” x 40” each. The solar designer provided the client with twelve combinations of different brands for solar panels and solar inverters. The customer selected a 7.9 kW system with Candian 330, CS1H-330MS solar panels and IQ7Plus Enphase Micro-Inverters for a 24 module layout Solar Kit.

With this chosen solar array, 88% of the household power is offset. The solar array will save the client approximately $1,993 of their annual utility costs. The solar array payback will take place in 4.75 years. The client will also receive a tax credit for their Solar Array purchase. This credit resulted in the final solar array NET cost of $9,460.

The roof is a composition shingle with 18 degrees of slope. IronRidge was selected to mount and rack the Solar Array to the roof with the IronRidge Flashfoot 2 and T-bolt. Due to the geographical location, snow load was 0 PSF, and a wind speed of 110 mph was calculated into the load assumption.

The next step was to layout the solar modules on the roof. As seen in the diagrams provided, three to four roofing sections were identified to configure the module layout, roof section weights, and roof section for all mounting segments. (The solar panels are represented in the diagrams below as light blue rectangles.) With these configurations, the segment length, cantilever, rail length, attachments, splices, and clamps are known for each roof segment. Three zoning groups were identified to determine the span details and reaction forces for mounting and racking. The total amount of mounting and racking equipment was calculated into the equipment needed for the final Canadian Solar Kit.  

Utility connection options were then outlined for 100 and 200 service Amps BUSS. A 200 Main Breaker Amps 200, with max solar breaker Amps 40, and 32 Max Solar Amps is set up to fit 9 to 10 kW with 40A breakers that vary by inverter.

Once the Solar Design was approved by the customer, a permit plan was created for compliance with local building and electrical Code. A Structural Engineer’s review and stamped letter was a requirement by the local building permit authority when submitting the plans. Once the plan was approved, the materials were delivered to the job site and work commenced.

This was a full-service, bumper-to-bumper installation project performed by SunWatts and a local, state-licensed contractor. After a few days of work, this family in San Mateo had a grid-tied solar-powered home. From start to finish, this project took less than three months to complete.

At SunWatts, we want to Make Solar Simple for you. The Solar Consulting and Design Service provides unbiased solar array brand options to support you in finding the best solar array for your needs. Call us at 888-498-3331 or contact us today to go solar!