# Haystack Fires in Australia: Causes and Considerations for Preventative Management
## 6 Introduction of 'Smart Agriculture' for Haystack Management
### Communication Technologies and Protocols
available wired and wireless communication technologies and protocols with their key characteristics compared. The advantages of IoT for monitoring haystacks over current methods are threefold. Firstly, compared to many of the current methods the data obtained are quantitative not qualitative, meaning greater accuracy (Tables 5 and 6). Secondly, it has the ability to obtain multiple measurements at different locations in a short period of time (Table 9). Finally, this data can be obtained remotely and transmitted to a central location with auto-generated alerts when pre-determined thresholds are exceeded. Limitations do exist for the use of IoT in haystack monitoring. In Australia, many haystacks or sheds are located away from other buildings and/or an electricity supply. The coverage range and power consumption may impact the suitability of some communication technologies to transmit the data obtained to the farmer or office (Table 9). While the vast majority of the Australian population (up to 99.5% depending upon carrier) have mobile phone coverage, in rural Australia there are still areas where the coverage is unreliable [101]. This limits the suitability of some communication technologies. Likewise, as the temperature of hay bales can increase rapidly (up to 5 \({}^{\circ}\)C in one hour (unreported data), the need for frequent monitoring may currently preclude the use of other technologies such as LEO satellites, which do not provide coverage 100% of the time. Finally, the large variability between individual bales in the parameters which may induce spontaneous combustion will require a large number of sensors to significantly reduce fire risk in a large stack. With a large number of sensors required, the ability to communicate the data obtained (Table 9) and the cost of the monitoring system may limit the rate of uptake by hay producers. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Technology (Standard)** & **Coverage Range** & **Theoretical** & **Maximum** & **Power** & **Market** \\  & **(m)** & **Data Rate** & **Number of Nodes** & **Consumption** & **Adoption** \\ \hline Ethernet & 100 & 10 Mbps- & 1 per wire (254 on & \\ (IEEE 802.3) & 100 & 100 Gbps & a subnet) & Low & High \\ PLCC (Insteon, IEEE 1901, & & 13 kbps- & & \\ CE bus, LonWorks) & 300–3000 & 200 Mbps & 500–1000 & Low–High & Low \\ Serial Comm. and & & & & & \\ Modbus (RS232, RS422, & 15–1200 & 1–10 Mbps & 32 typical. Up to & Low & High \\ RS485) & & & & & \\ Zigbee & 10–100 & 250 kbps & 255 & Low & High \\ (IEEE 802.15.4) & 10–50 & 2–24 Mbps & 8 & High & High \\ (IEEE 802.15.1) & 50–70 & 11–1300 Mbps & 255 & High & High \\ WiFi & 50–70 & 11–1300 Mbps & 255 & High & High \\ (IEEE 802.11 a,b,g,n,ac) & & & & & \\ EnOcean & 20–200 & 125 kbps & 232 & Low & Low \\ (EnOcean standard) & & & & & \\ BACnet & 1200 & 9.6–115.2 kbps & 32 typical, up to & Low & Low \\ (ANSI/ASHRAE 135) & 10–100 & 250 kbps & 100 & Low & Low \\ 6 LoWPAN & 10–100 & 250 kbps & 100 & Low & Low \\ (IEEE802.15.4) & 30–300 & 100 kbps & 232 & Low & Low \\ \(Z\)-Wave Alliance & & & & & \\ LoRaWAN & 10,000 & 0.3–50 kbps & 2000–3000 & Low & Low \\ (LoRa Alliance) & & & & & \\ LEO & 500–2500 km & 1–40 Mbps & \textgreater{}1 million & Low & Low \\ (Low Earth Orbit Satellite) & \textasciasci{}1000 (urban) & 200 kbps & Up to 50,000 & Low & High \\ NB-IoT (Narrowband IoT) & \textasci{}10,000 (rural) & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Key characteristics of prominent wired and wireless communication technologies (updated from [49]).