Pecan Street Inc - Austin, Texas

Juris K.

I have several questions about your study:
1. revenue grade meters on residential systems are generally not accurate and may not be calibrated to similar standards from system to system. How do you take into account uncertainties in them? My understanding is they cannot be expected to be better than +/- 5%, much greater than the accuracy of the results you claim in your article.
2. what standard module performance parameters do you use to estimate your expected energy output in kWh/kW of rated system capacity? Modules from different vendors may have different errors on the nameplate power, and also different temperature coefficients of degradation with rising temperature.
3. as you likely know, modules facing south at high noon will run hotter than those facing west. In addition, module mounting configuration influences operating temperature; also prevailing wind patterns, which can cool modules to different extents unless they are mounted so as to compensate for these factors. How do you account for degradation with temperature differences in your sample? Do you measure module temperatures and compensate for differences?

In general, I would say any one of these factors could wipe out your perceived advantage of 2% for west-facing modules.

Suzanne R.

Pecan Street Inc. is a world-class research and development organization accelerating innovations in clean energy and smart water. A great organization that is changing the world.

Kevin P.

Absolutely one of the real old skool breweries I have found. Great food and excellent customer service

Bert H.

Helping humans survive the next century.

Ruth S.

Limited parking

Chuck B.