LoRa　modulation　is　a　narrowband,　long-range　wireless　communication　technology.　At　present,　Sub-GHz　LoRa　is　mainly　used　to　build　LoRaWAN　and　is　applied　to　data　collection　of　Internet　of　Things.　However,　the　latest　2.4 GHz　LoRa　can　be　applied　to　point-to-point　and　self-organizing　networks.　In　this　paper,　the　impacts　of　bandwidth　(BW)　and　spreading　factor　(SF)　on　the　energy　consumption　is　evaluated　for　the　first　time.　In　general,　to　reach　the　target　transmission　distance,　a　larger　SF　or　a　smaller　BW　can　be　selected　to　reduce　transmitting　power　(but　the　ToA　time　will　increase　in　this　case),　or　the　desired　transmission　distance　can　be　achieved　by　increasing　the　transmitting　power　and　keeping　a　smaller　SF　or　a　larger　BW.　obviously,　both　of　them　will　increase　the　power　consumption　of　transmission.　We　analyze　which　method　is　more　energy-efficient　by　constructing　an　energy　consumption　model　for　LoRa　communication.　The　energy　model　is　suitable　for　the　adaptive　data　rate　(ADR)　of　LoRa　and　establishes　the　foundation　for　building　low-energy　node-to-node　and　Ad-hoc　LoRa　networks.　©　2022,　ICST　Institute　for　Computer　Sciences,　Social　Informatics　and　Telecommunications　Engineering.