ASTM E2848-11e1
Standard Test Method for Reporting Photovoltaic Non-Concentrator System Performance

Standard No.

ASTM E2848-11e1

Release Date

2011

Published By

American Society for Testing and Materials (ASTM)

Status

Be replaced

Replace By

ASTM E2848-13

Latest

ASTM E2848-13(2023)

Scope

5. Significance and UseTop Bottom

5.1 Because there are a number of choices in this test method that depend on different applications and system configurations, it is the responsibility of the user of this test method to specify the details and protocol of an individual system power measurement prior to the beginning of a measurement.

5.2 Unlike device-level measurements that report performance at a fixed device temperature of 25??C, such as Test Methods E1036, this test method uses regression to a reference ambient air temperature.

5.2.1 System power values calculated using this test method are therefore much more indicative of the power a system actually produces compared with reporting performance at a relatively cold device temperature such as 25??C.

5.2.2 Using ambient temperature reduces the complexity of the data acquisition and analysis by avoiding the issues associated with defining and measuring the device temperature of an entire photovoltaic system.

5.2.3 The user of this test method must select the time period over which system data are collected, and the averaging interval for the data collection within the constraints of 8.3.

5.2.4 It is assumed that the system performance does not degrade or change during the data collection time period. This assumption influences the selection of the data collection period because system performance can have seasonal variations.

5.3 The irradiance shall be measured in the plane of the modules under test. If multiple planes exist (particularly in the case of rolling terrain), then the plane or planes in which irradiance measurement will occur must be reported with the test results. In the case where this test method is to be used for acceptance testing of a photovoltaic system or reporting of photovoltaic system performance for contractual purposes, the plane or planes in which irradiance measurement will occur must be agreed upon by the parties to the test prior to the start of the test.

Note 1???In general, the irradiance measurement should occur in the plane in which the majority of modules are oriented. Placing the measurement device in a plane with a larger tilt than the majority will cause apparent under-performance in the winter and over-performance in the summer.

5.3.1 The linear regression results will be most reliable when the measured irradiance, ambient temperature, and wind speed data during the data collection period are distributed around the reporting conditions. When this is not the case, the reported power will be an extrapolation to the reporting conditions.

5.4 Accumulation of dirt (soiling) on the photovoltaic modules can have a signific...........

ASTM E2848-11e1 history

• 2023 ASTM E2848-13(2023) Standard Test Method for Reporting Photovoltaic Non-Concentrator System Performance
• 2018 ASTM E2848-13(2018) Standard Test Method for Reporting Photovoltaic Non-Concentrator System Performance
• 2013 ASTM E2848-13 Standard Test Method for Reporting Photovoltaic Non-Concentrator System Performance
• 2011 ASTM E2848-11e1 Standard Test Method for Reporting Photovoltaic Non-Concentrator System Performance
• 2011 ASTM E2848-11 Standard Test Method for Reporting Photovoltaic Non-Concentrator System Performance