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Effect of PV Array Orientation - Phoenix AZ

The following chart shows the calculated PV system output for a system in the Phoenix, Arizona area for a variety of array orientations. The calculations assume an open array in free air such as a pole mount or parking canopy without anything under the modules. Mounting PV modules on a roof reduces the output due to the higher temperatures. PV modules mounted flush with a roof, but with at least 3” of space below the modules and mounting structures that allow some air flow, will have an annual energy reduction of about 6%. Of course, these calculationa assume no shadows on the PV array.  The calculations include normal inverter efficiency, wire loss, and an allowance for dirt.
 
In the chart the upper line shows the roof pitch (4/12 represents 4" of slope per 12" of roof), the angle the pitch represents, and the direction the PV module face (NW=North-West, etc.).The larger number is the annual output in kilo-Watt-hours (kWhr) per year for a PV array with a nominal rating of 1000 Watts.  For instance, if the PV array has 20 PV modules with a rating of 310 watts (STC) per module, the array is rated 6.2 kilo-Watts DC (kWdc). To estimate the annual output using this chart, simply select the closest orientation, such as South facing at 3/12 pitch, and multiply the 1668 by 6.2 to get the annual output of 103,416 kWhr.
kWhr vs orientation Phx

After APS explosion injures 4 firefighters, Arizona cities enact battery storage laws for utilities, homeowners

There is an interesting, but non-technical, article in the Arizona Republic about batteries in PV systems.

Most of the major Phoenix area cities have documents that detail the requirements for new solar systems and it is likely that the cities will be updating their documents soon with battery requirements.

After APS explosion injures 4 firefighters, Arizona cities enact battery storage laws for utilities, homeowners

First Solar exits the EPC business

SEPTEMBER 20, 2019

Citing the wild success of its Series 6 module, First Solar has announced that it is closing its engineering, procurement and construction business in the United States in order to concentrate on scaling, developing, and selling modules.

There is no further news on the First Solar website, but this seems to be unwelcome news for Tempe.

See the pv magazine USA article for more detail: First Solar exits the EPC business

Proposed changes impacting photovoltaic (PV) installations in the 2020 National Electrical Code (NEC)

A look at some of the more significant changes under consideration for the 2020 National Electrical Code (NEC) that will affect future distributed generation systems (solar electric wind, etc.). Article 690, Solar Photovoltaic (PV) Systems and Article 705, being renamed Interconnected Electric Power Production Sources, are specific to distributed generation.

The referenced article below by IAEI, a membership driven, non-profit association promoting electrical safety, has a good summary of upcoming changes.

https://iaeimagazine.org/magazine/2019/09/10/pv-installations-for-the-2020-nec/