Wondering about a solar energy system installation for your home or business? The steps involved in installing solar power are outlined in the following article. It's not meant to be a detailed report answering all your questions, as information is available elsewhere on this site, but it will illustrate how a solar power system is installed.
Follow the step-by-step installation of a 10 kW solar energy system with a dual axis solar tracker manufactured by DEGERenergy.
The top soil is excavated in preparation for pouring the concrete foundation. A frost-proof sub-base or concrete fill down to the frost line is necessary in northern regions prone to frost. Once compacted aggregate fill has been added to the excavation, a bottom layer of wire-mesh steel is inserted.
The mast mount is inserted and bent bar-steel reinforcement is installed to reinforce the base. The mast is positioned and carefully aligned vertically, and the top layer of wire-mesh steel is inserted. Conduit is inserted for cables, and the mast is secured with reinforcement dowels against unwanted rotation.
The form-work is created and made level. The conduits for electrical cables can be seen protruding from beneath the form-work.
The concrete is poured into the form-work while high frequency vibrators ensure that it's properly compacted. A band has been placed around the form-work to ensure any pressure generated by the cement filling can be absorbed.
The finished concrete base is allowed to harden for several days before any further installation work is undertaken.
The east-west rotating head is lowered onto the flange on top of the mast and positioned to true south before fastening to the mast.
The limit switch is installed to limit east-west rotation, and control boxes are attached.
The base frame is assembled making sure the tension rods are installed according to spec, and the positions of the aluminum profiles are marked on the cross braces to assist with their installation.
The aluminum profiles are attached to the base frame, arranged symmetrically to the center of gravity. The profiles are required for fastening each row of solar modules (solar panels) to create the solar table.
The rows of solar panels (modules) are securely fastened to the aluminum profiles in their specified positions. The modules are positioned from the center outwards to ensure precise symmetry so their weight will be evenly distributed across the solar table.
The solar table is raised by a crane and positioned for its attachment to the mast. It's important to monitor weather conditions before and during the solar energy system installation. Strong winds and lightening are hazardous when lifting the heavy components with a crane.
The solar table is gently lowered onto the mast and securely fastened to the rotating head.
The remaining solar panels are installed in the areas of the solar table that had to be left open because of the crane's lifting straps.
The modules are now electrically connected following the solar panel wiring diagram, and all cable connections are tested for reliable current flow and to ensure they meet the electrical safety code requirements.
The elevation motor is attached to the base frame and to the rotation head. Should the electrical components ever fail, the system can be moved into the safe, horizontal position by using a standard spanner wrench to turn the elevation motor.
The sunlight sensor continuously measures the insolation (incoming solar radiation). Once it detects the brightest spot in the sky, it adjusts the array's position to face it. It serves to keep the modules perpendicular (90°) to the sun's rays throughout the daylight hours.
The constant positioning increases the daily energy gain by as much as 40% compared to stationary ground mounted systems, depending on the latitude of the location.
The sunlight sensors are mounted on the edge of a solar panel at the top and west side of the solar table.
The two sunlight sensors (see arrows in photo above) automatically control each axis of rotation. The west sensor is attached to the west side of the solar table to control the east-west rotation, and the elevation sensor is mounted to the top of the solar table to control the table's elevation.
During heavily overcast weather, fog, rain, or twilight conditions, the tracker table will move to the horizontal position or face the brightest patch of sky.
The wind sensor is coupled to an anemometer (a rotating instrument for measuring the speed of the wind). It is designed to trigger a wind alarm only when there's a permanently strong wind, and it will not respond to temporary wind gusts. When the wind reaches a steady 12 m/s, the tracker will move to a horizontal position, a factory-designated safe position.
The snow sensor is mounted to the edge of a solar panel situated at the bottom of the solar table. If the surfaces of the snow sensor and the solar panels are both snow covered, and the sensor can measure a specified layer of snow or ice, the array will be moved to its maximum vertical position.
Once the tracker table is at its maximum vertical position, the snow and ice can slide off and the table will return to its standard position facing the brightest region of the sky, allowing the PV panels can harvest the sun's rays.
The central control box connects the wind, snow, and insolation sensors to ensure the tracker's safe and productive operation. A joystick provides the ability to control the tracker's position manually by overriding the automated operation for times of testing or repair.
The solar tracker depends only on solar energy from the array to function, taking no more than 1 to 3 Watts from the array while operating and zero Watts throughout the night. However, there is a 12-volt battery backup system available to provide operating power during times of extreme overcast skies.
A trench is dug from the tracker base to the foot of the electric grid pole to contain the conduit and electrical wiring.
The conduit trench is refilled, and the excavated area is ready for landscaping.
Since this solar energy system installation is a grid-tie system, it's electrically connected to a meter located on the utility pole to accurately meter how much electricity it's exporting to the grid. Installing a grid-tie system is similar to installing a non grid system, except you don't have a battery system to store the electrical energy.
The solar tracker is now completely installed and the solar energy system installation is fully operational. A wire mesh fence will be installed for security.