Response to two posts - the solar cells on the Ambient Weather station serve to power the station when enough sunlight is available, and also charge a super-capacitor inside for other times. The batteries serve as backup for when there's not enough light, and the super-capacitor is discharged. Lithium AA batteries are great for this purpose. From Energizer's web site -
Nothing outlasts
Energizer® Ultimate Lithium™ AA batteries. The
Energizer® Ultimate Lithium™ batteries are not only the #1 longest-lasting AA batteries…they are complete with leak resistance and performance in extreme temperatures (-40ºF to 140ºF or -40ºC to 60ºC). To ensure your favorite devices operate at their peak performance, depend on
Energizer® Ultimate Lithium™batteries for work, play and home.
Energizer Ultimate Lithium™ batteries are 100% leak proof*
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I chose to have a personal WS because, as stated above, the conditions at my property are significantly different than the nearest station reported on by Weather Underground and I want to know
my weather!
Also, when I check my station remotely, especially when out of town, if I get a current reading I know that power and Internet are up. I don't take those for granted, having PGE for electricity. For those who don't know, PGE stands for Part-time Grid Energization.
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One last note - I also go to the National Weather Service web page -
National Weather Service - and enter my zip code in the upper right hand of the page. On that page, there is a map displayed with an option to click your actual location. This gives you the conditions of the station closest to you.
In my case, it's much more aligned with what my own WS tells me than the "generic" readouts otherwise given.