Institute for Earth Science Research and Education*
December, 2006

Pyranometers and broadband/near-IR reflectometers

The following instruments are now available from the Institute for Earth Science Research and Education in kit or assembled/calibrated form:

1. Pyranometer
      This simple solar cell-based pyranometer (an instrument for measuring solar energy reaching Earth's surface) is similar in principle to much more expensive commercial solar cell-based pyranometers. It is intended for data collection with a U12-006 or U12-013 (shown below) 12-bit data logger from Onset Computer Corporation. Other 12-bit data loggers (but not 8- or 10-bit loggers) can be used, but the 2.5mm stereo plug will probably not work as an input connector to such devices. You can find construction details here.

A completed instrument needs to be calibrated to give quantitatively accurate results. Ideally, this calibration should be done against a commercial pyranometer (this service is available from IESRE), but an approximate calibration can be obtained by using a computer model of solar irradiance under clear skies, available online. Construction is simple and requires only two solder connections. It is a suitable project for secondary and middle school students, with appropriate supervision. A detailed construction guide and supporting documentation are available online.

The price for the kit (not including the data logger) is $20, including shipping in the U.S.
Assembled instruments calibrated against an Apogee Instruments PYR-P pyranometer are available for $75, including shipping in the U.S.

2. Broadband/near-IR radiometer/reflectometer.
      This instrument uses the same detector as the pyranometer, with the addition of a second detector that is identical except that its spectral response is limited to the near-IR part of the solar spectrum. As there are no exactly comparable commercial instruments, the near-IR detector does not lend itself to an absolute radiometric calibration for comparisons against other data sources. Its primary use is in pairs as a two-channel reflectometer, with one instrument pointed straight up and the other straight down. Surfaces typically have different reflectivities in the near-IR than in the visible, so these measurements are interesting for comparing surfaces, especially vegetated surfaces. When used in pairs, one instrument is provided with the bubble level on the bottom of the case.

The price for the kit version of this instrument (not including the data logger) is $35, including shipping in the U.S.
Assembled and tested instruments are available for $75. An absolute calibration of the broadband detector against an Apogee Instruments PYR-P pyranoemter is available for an additional $25.

An order form for this and other atmosphere monitoring instruments here.

Send orders to:
David Brooks
Institute for Earth Science Research and Education
2686 Overhill Drive
Eagleville, Pennsylvania 19403
USA

Check, cash, money order, or PayPal. If you use PayPal, please add the greater of $1 or 3% to cover transactions costs. For more information, e-mail David Brooks.

*The Institute for Earth Science Research and Education is a 501(c)(3) corporation incorporated in Pennsylvania.