Gateway Placement & Analysis Tools

As with any antenna, the placement of the Tigo gateway is important. Things like aluminum soffit (commonly used for the ceiling of outdoor patios) and facia, metal conduits, and electrical wiring can make effective RF shields or introduce enough RF noise as to interfere with proper gateway operation.

Initially, I had hoped to place the Tigo gateway inside a portion of the roof facing towards the solar module array, above the plane of the array (understanding that the LMUs are below the plane of the array). Unfortunately, the combination of facia, conduit, electrical wiring and the relationship of the gateway to the plane of the array resulted in poor gateway communication with each LMU.

Tigo's website is a perfect tool for diagnosing such communication problems. On the right is an example of the Tigo 'Summary' page for my installation. Note the two panels showing in gray. Gray indicates a some kind of module failure; a communication failure in this case. At the bottom left of the page is a tool for scrolling through a day's worth of solar production data. If when dragging that scroller one sees frequent gray panels a communications problem is the likely culprit.

Tigo's website also provides extremely detailed information on an 'Advanced' page. This data is downloadable in CSV format, suitable for importing into your favorite spreadsheet, and can be as fine as one sample per second. Evaluating the downloaded data by looking for gaps in reported data can assist in the diagnosis of panel problems. If a single panel's LMU never reports data then there may be a panel problem. One can then report this to their installer so that the search for the problem is simplified.

What one wants, of course, is a presentation showing all green panels with relatively similar wattage amounts, as shown to the right. Data for past dates can be brought up by clicking on the calendar control at the bottom left and choosing the desired data. The day's recorded data can be 'played' by pressing the 'play' button. And the total day's accumulated production can be seen at the bottom right.

In my case, gateway placement was causing communications issues so I tried different placements over a few days. In consultation with Tigo's Stuart Davis, we identified a number of candidate placements. The optimum location would be within the attic just below the top row of panels and generally facing towards all panels. Unfortunately, that would be a difficult location to get to. Ultimately, I settled on a location about 25 feet in front of and two feet up from the bottom of the array. The gateway will be mounted on a short pole from the side of the house and face directly towards the array.

With this setup, things are working extremely well, and, on sunny days, I am seeing about 35kWh of production. I expect this number to rise as the days get longer.

Our March Rocky Mountain Power bill was, once again, one half of what it had been a year ago.

Production Analysis

The Tigo web site has several other important tools for analyzing power production. The 'Energy' page can show the performance of the entire array or individual solar modules. On the right is a daily snapshot hour-by-hour of my system for April 7th.

On the left is a weekly snapshot showing day-by-day production from April 3rd for seven days. Clearly, the 5th and 6th were cloudy days with low production, but the 8th was a terrific day for production.