Wireless sensor networks have become an important tool for
modern farmers (Coates et al., 2013). For scalar sensors conserving
energy is critical (Suh et al., 2008). The results of the implementation
of LPL function for energy saving are summarised in Table 1. It
is shown that without LPL function, even lithium battery, does not
last a full week, because the radio module is consuming about 20
mA all the time. These values are similar to those obtained at 4.5