[RE-wrenches] Using the North Facing Roof

[Jason Szumlanski]

We get this question all the time, mostly due to aesthetic concerns. The
location is obviously a huge factor in this decision, but the mounting
pitch is also very important. I did a PVWATTS-based study recently based on
our local area, and the results are here:

http://floridasolardesigngroup.com/solar-electricity-output-based-on-tilt-and-orientation/

Other related resources:

http://floridasolardesigngroup.com/pitch-solar-panels-on-my-roof-is-it-necessary/
http://floridasolardesigngroup.com/can-i-put-solar-panels-on-my-north-roof-in-southwest-florida/


The bottom line is that the marginal cost of adding solar panels to a north
roof may be completely viable in some scenarios, and even a completely
north facing array in others. It often depends on the investment
requirements of the buyer. I can see benefits to off-grid systems, too,
where production on even a north vertical wall can provide critical power
at certain times of day at certain latitudes. If aligning production with
consumption is important in a situation, every pitch and azimuth is on the
table for analysis.


Jason Szumlanski

Florida Solar Design Group



On Tue, Jul 28, 2015 at 1:21 AM, Peter Parrish <
peter.parrish at calsolareng.com> wrote:

> I recently read a short piece that caught me up short, and I quote:
>
> “The fast dropping cost of solar, while a huge boon to the adoption of
> solar PV, has counter-intuitively altered design parameters. No longer is
> the north-facing roof considered unusable because limited application in
> less-than optimal orientations can still show a positive net benefit.
> Arrays are thus designed now with elements or sub-arrays in these
> locations, increasing overall kW installation while reducing the energy
> production per capacity installed. This might have been anticipated based
> on sheer economic analysis from a users perspective, but so long has solar
> been expensive that these less optimal orientations were never seriously
> considered.”
>
>
>
> I doubt that the individual who wrote this piece came to these conclusions
> him/herself. Does anyone know of a recent article that argued this
> perspective? Is this an emerging design practice? If so, I’d like to know
> more about it.
>
>
>
> -          Peter
>
>
>
> Peter T. Parrish, Ph.D.
>
> President, SolarGnosis
>
> 1107 Fair Oaks Ave., Suite 351
>
> South Pasadena, CA 91030
>
> (323) 839-6108
>
> petertor at pobox.com
>
>
>
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