Project Spotlight: 25.5 Kilowatt Ground Mounted Solar Photovoltaic Installation in El Dorado Hills
Reducing electrical expenses and environmental impact are two big reasons people install solar power at their home or office.
Here's a behind-the-scenes look at a recently completed solar job in El Dorado Hills.
This project presented it's challenges, but we were pleased to meet our clients goals by doing what we do best: designing and installing intricate PV systems.
What was the project and what were the client's goals?
The project was to install a Solar PV system on a residential property to serve two houses on the same property. The client's main goals were to reduce their ongoing electricity expense through a ground mounted system with two arrays.
Why did they decide to complete the project?
The clients were seeking freedom from costly PG&E electrical bills.
Time to complete the project?
This particular project took a few months for us to complete, due to the intricacies of the project.
This like most projects follow a similar pattern
We calculated the customers energy consumption for the two houses to get a baseline.
Then we configured the best possible PV array layout (within engineered calculations to properly support and secure the arrays) and designed the electrical configuration to supply the PV power from the ground mount arrays
In this case, that meant two trenches all the way back to the main panel.
We then installed grounding rods and De-rated the main breakers for both service panels.
Lastly, we had to contact PGE to get pre-inspection of the system size – to determine what was allowable for the system size to connect both arrays back to the customer’s service panel and allow operation back to PGE grid.
Unique Challenges Techniques, Technologies and Approaches
The first unique challenge was the layout of the electrical configuration and the solar array layout (racking and structure). The electrical for the arrays required us to use four guys and a winch to pull the bundle of power supply and ground wires through conduit up to the main panels.
For the main panels, we had a total of 85 (300 W Solar World panels) connected with 85 IQ6 Enphase micro-inverters – the two arrays together total - a 25.5 kW system (in layman’s terms, that a lot! - what is a Kilowatt Hour?)
This particular ground mount required us to dig the footings to about 4 ft deep by 24 inches round (which took about ½ yd per concrete per footing).
The other big challenge was the soil.
Large rocks had to be removed and we had to trench two trenches (at total of about 300 ft in length - at 24” inches deep) through compacted red clay to lay the wiring and conduit into the trench.
