Yes - it’s officially fall, and the days are shorter. Rain has started and electrical loads are increasing as lights come on sooner. That solar system which performed admirably all summer is becoming taxed and it's batteries are working harder than ever.
Its never been a better time for an upgrade! Power shortages can be a thing of the past with the simple addition of 1 or 2kW of solar panels. Here’s how:
Locating More Solar Panels:
More cottages are placing solar on ground mounts, as roof spaces may be limited, in shade, or facing the wrong way. Ground mounted solar allows the solar panels to be placed in an area with better exposure and facing south. They also allow a tilt angle of 45 degrees – ideal for fall production.
High voltage controllers open up options for solar systems location that were not considered 10 years ago. This is because the panels are wired in series to a DC voltage of 150DC, and some controllers allow even higher DC voltage (Magnum PT100 and Classic-250).
The array can be placed up to 200 feet away from the batteries – if the cable is sized correctly.
Solar Panels Options:
Since ground mounts are not space constrained, the larger 72 cell solar panels are popular. Most economical are the 345W options like the Hansol HS-345 and Q-Cells 345W. HES also stocks 365W and 370W 72 cell solar panels.
Mounting the Solar Panels:
Some options to support the solar panels are Pole Mounts and Ground Mounts.
A six panel pole mount fits on a single 6” pole. Using the 72 cell 345W panels gives 2.07kW of power, or with 370s, 2.33kW. These mounts require a concrete foundation. See the Pole Mount section on the HES website for products and footing ideas.
A lower cost approach is a single tier Ground Mount kit. The installation requires 2 parallel beams about 1m apart. These can be made with 4x4 pressure treated lumber, and sonotube footings. The mount uses Fast-Rack rails to support the panels and includes system electrical bonding. A 2kW solar ground mounted array is roughly 6m long (~20’) and a 1kW system 3m (~10’).
Wiring the Solar Panels:
Most MPPT charge controllers, like the Outback FM-60, EPS MPPT-40-BN and Classic 150 allow up to 150V DC solar input. Three modules in series is perfect. A combiner like the Midnite MNPV3-250 is used to bring the 1 or 2 strings together from the solar array, and transitions to a TECk armoured cable. The cable size must be chosen to move 8/16 amps of current over the appropriate distance. Consult the Canadian Electrical Code for wire sizing guidelines.
Charge Controllers for 1 and 2 kW Solar Arrays:
Most often additions to solar systems use a dedicated charge controller. Since MPPT charge controllers convert high voltage DC power to the battery voltage, the charge currents are high. This means the charge controllers are located close to the batteries. A 2kW array could deliver 80 amps of current.
It has never been cheaper to buy solar panels than this fall. For most cottage systems, and addition of 1 or 2kW is easy, and can work in parallel with an existing solar system. Ground mounting is economical and opens up options as to where the solar can be located. So, dealing with power shortages by adding to an existing solar system has never been easier than today.