干旱区生态环境知识资源中心

The energy yield of a system depends largely on how the photovoltaic (PV) panels perform at different weather conditions (particularly plane of array irradiance and module temperature) summed over the hourly meteorological data for a year at the given site. Some of the PV performance parameters such as efficiency at low light/efficiency at standard conditions' and the P-MAX thermal coefficient' can vary between technologies and may be able to be improved by better production methods (for example, improving uniformity, reducing shunts, reducing series resistance or improving the thermal design). The sensitivity of energy yield (kilowatt hour/year) against PV input value will be site dependent, for example, high insolation sites will usually experience higher module temperatures so that improvements in temperature coefficients would be more beneficial at higher than at lower insolation. This study studies the effect of the sensitivity of energy yield at five different sites (from northern Europe to desert) of six different PV input values (including low-light efficiency, P-MAX temperature coefficient and nominal operating cell temperature). It quantifies the benefits at each site of good temperature coefficients or improving the low-light efficiency and also the need for wide V-MP inverter ranges at sites with wide seasonal temperature differences.