This is an Arduino powered Weather Station Project that can run on batteries for almost a year! In order to achieve that we use a bare ATMEGA328 chip along with some accurate sensors. We use the DHT22 temperature and humidity sensor, a BMP180 barometric pressure sensor, a BH1750 light intensity sensor and a Nokia 5110 LCD display. We use the low power library in order to greatly reduce the power consumption of the project and we disable the lcd display when it is night.
Weather Station Project with ATMEGA328P, DHT22, BMP180, BH1750 and a Nokia 5110 LCD – [Link]