Evaluation of a wireless solar powered personal weather station

Authors: Lascano, Robert; Goebel, Tim; Gitz, Dennis; Stout, John

Submitted to: Agricultural Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/17/2023
Publication Date: 1/12/2024
Citation: Lascano, R.J., Goebel, T.S., Gitz, D.C., Stout, J.E. 2024. Evaluation of a wireless solar powered personal weather station. Agricultural Sciences. 15(1). https://doi.org/10.4236/as.2024.151003.
DOI: https://doi.org/10.4236/as.2024.151003

Interpretive Summary: USDA-ARS Scientists of the Wind Erosion and Water Conservation Research Unit are working with cotton dryland producers in Martin County, TX to quantify the relation between rainfall and cotton dryland lint yield. For this purpose, we wanted to install rainfall gauges in as many fields as possible and our target was to have one rain gauge per 600 Acres. As we started this project, we came to the realization that the type of rainfall gauge we needed, for example, a tipping bucket rain gauge that was both wireless and solar powered cost about $1,000 US dollars. We searched for an alternative method and came across a commercial all-in-one weather station, referred to as Personal Weather Station (PSW) that is both wireless and solar powered. These PWS have a cost of about $200 US dollar per unit and for practical purposes are disposable. We evaluated not only the measurement of rainfall, but also the measurement of air temperature and humidity, solar radiation, calculated dew-point temperature and wind-speed. Our evaluation consisted of comparing average values of the weather variables measured with four units of the PWS to corresponding values measured with the USDA-ARS weather station located in our facilities in Lubbock. We did this comparison for 242 days (October 2022 to May 2023) and our results indicated no statistical differences between the two measurements. As expected, the measurement of radiation and wind-speed were the most variable. The measurement of rain agreed; however, our largest single rain event was 1-inch, and we expect a discrepancy for larger values. We conclude that for our purpose the selected PWS is more than adequate to measure rainfall as well as other weather variables.

Technical Abstract: We are evaluating dryland cotton production in Martin County, Texas measuring cotton lint yield per unit of rainfall. Our goal is to collect rainfall data per 250 – 400 ha. Upon selecting a rainfall gauge, we realized that the cost of using, for example, a tipping bucket-type rain gauge would be too expensive and thus searched for an alternative method. We selected an all-in-one commercially available weather station, hereafter, referred to as a Personal Weather Station (PWS) that is both wireless and solar powered. Our objective was to evaluate average measurements of rainfall obtained with the PWS and to compare these to measurements obtained with an automatic weather station (AWS). For this purpose, we installed four PWS deployed within 20 m of the Plant Stress and Water Conservation Meteorological Tower that was used as our AWS, located at USDA-ARS Cropping Systems Research Laboratory, Lubbock, TX. In addition, we measured and compared hourly average values of short-wave irradiance (Rg), air temperature (Tair) and relative humidity (RH), and wind speed (WS) and calculated values of dewpoint temperature (Tdew). This comparison was done over a 242-day period (1 October 2022 – 31 May 2023) and results indicated that there was no statistical difference in measurements of rainfall between the PWS and AWS. Hourly average values of Rg measured with the PWS and AWS agreed on clear days, but PWS measurements were higher on cloudy days. There was no statistical difference between PWS and AWS hourly average measurements of Tair, RH, and calculated Tdew. Hourly average measurements of Rg and WS were more variable. We conclude that the PWS we selected will provide adequate values of rainfall and other weather variables to evaluate dryland cotton yield per unit rainfall.