Weird behaviour, During the night, Mac wakes every hour on it's own and does this - log attached, any idea why?

This pattern repeats once every hour?

12/12/2014 04:20:59.000 kernel[0]: Wake reason: RTC (Alarm)
12/12/2014 04:20:59.000 kernel[0]: RTC: SleepService 2014/12/12 04:20:59, sleep 2014/12/12 03:21:01
12/12/2014 04:20:59.000 kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
12/12/2014 04:20:59.000 kernel[0]: AppleCamIn::wakeEventHandlerThread
12/12/2014 04:20:59.000 kernel[0]: Previous Sleep Cause: 5
12/12/2014 04:20:59.000 kernel[0]: AppleHSSPIController::HandleMessage Device Wake by Host
12/12/2014 04:20:59.000 kernel[0]: AppleThunderboltNHI::prePCIWake - power up complete - took 180846 us
12/12/2014 04:20:59.000 kernel[0]: AppleThunderboltHAL::earlyWake - complete - took 1 milliseconds
12/12/2014 04:20:59.258 hidd[70]: MultitouchHID: device bootloaded
12/12/2014 04:20:59.000 kernel[0]: Thunderbolt Self-Reset Count = 0xedefbe00
12/12/2014 04:20:59.000 kernel[0]: IOThunderboltSwitch<0xffffff8028fed800>(0x0)::listenerCallback - Thunderbolt HPD packet for route = 0x0 port = 11 unplug = 0
12/12/2014 04:20:59.000 kernel[0]: TBT W (2): 0x0100 [x]
12/12/2014 04:20:59.000 kernel[0]: IOThunderboltSwitch<0xffffff8028fed800>(0x0)::listenerCallback - Thunderbolt HPD packet for route = 0x0 port = 12 unplug = 0
12/12/2014 04:20:59.000 kernel[0]: ARPT: 91334.258121: si_survive_perst_war: bar0win before 18003000, bar0win after 18001000
12/12/2014 04:20:59.000 kernel[0]: ARPT: 91334.261266: pcicore_pci_pmeclr PMECSR : 0x4008
12/12/2014 04:20:59.000 kernel[0]: ARPT: 91334.261275: pcicore_pmestatclr PMECSR : 0x4008
12/12/2014 04:20:59.000 kernel[0]: ARPT: 91334.261378: pcicore_pci_pmeclr PMECSR : 0x4008
12/12/2014 04:20:59.000 kernel[0]: en0: BSSID changed to 60:33:4b:e1:53:1c
12/12/2014 04:20:59.000 kernel[0]: ARPT: 91334.507572: AirPort_Brcm43xx::powerChange: System Wake - Full Wake/ Dark Wake / Maintenance wake
12/12/2014 04:20:59.000 kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
12/12/2014 04:20:59.000 kernel[0]: AppleCamIn::wakeEventHandlerThread
12/12/2014 04:20:59.662 airportd[84]: _doAutoJoin: Already associated to “Airport - TC1TB (5 GHz)”. Bailing on auto-join.
12/12/2014 04:21:01.049 ntpd[44]: ntpd: wake time set +0.310571 s
12/12/2014 04:21:01.070 com.apple.time[164]: Interval maximum value is 946100000 seconds (specified value: 9223372036854775807).
12/12/2014 04:21:01.076 com.apple.time[164]: Interval maximum value is 946100000 seconds (specified value: 9223372036854775807).
12/12/2014 04:21:04.000 kernel[0]: AppleCamIn::handleWakeEvent_gated
12/12/2014 04:21:04.000 kernel[0]: AppleCamIn::handleWakeEvent_gated
12/12/2014 04:21:46.223 ntpd[44]: ntpd: wake time set -0.148252 s
12/12/2014 04:21:46.241 com.apple.time[164]: Interval maximum value is 946100000 seconds (specified value: 9223372036854775807).
12/12/2014 04:21:46.247 com.apple.time[164]: Interval maximum value is 946100000 seconds (specified value: 9223372036854775807).
12/12/2014 04:21:46.000 kernel[0]: ARPT: 91381.078880: AirPort_Brcm43xx::powerChange: System Sleep 
12/12/2014 04:21:46.000 kernel[0]: ARPT: 91381.078889: wl0: powerChange: *** BONJOUR/MDNS OFFLOADS ARE NOT RUNNING.
12/12/2014 04:21:46.000 kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
12/12/2014 04:21:46.000 kernel[0]: ARPT: 91381.566519: scanparams:
12/12/2014 04:21:46.000 kernel[0]: ARPT: 91381.566524: flags 0
12/12/2014 04:21:46.000 kernel[0]: ARPT: 91381.566526: active_time 0, passive_time 0
12/12/2014 04:21:46.000 kernel[0]: ARPT: 91381.566528: scan_start_delay 0
12/12/2014 04:21:46.000 kernel[0]: ARPT: 91381.566530: scan_cycle_idle_rest_time 0, scan_cycle_idle_rest_time_multiplier 0
12/12/2014 04:21:46.000 kernel[0]: ARPT: 91381.566533: max_scan_cycles 0, max_rest_time 0
12/12/2014 04:21:46.000 kernel[0]: ARPT: 91381.566535: Scan Channels (0): None
12/12/2014 04:21:46.000 kernel[0]: ARPT: 91381.566537: SSID (0): None
12/12/2014 04:21:46.000 kernel[0]: ARPT: 91381.566539: SSID count = 0
12/12/2014 04:21:46.000 kernel[0]: ARPT: 91381.566541: wl0: leaveModulePoweredForOffloads: Wi-Fi will stay on.
12/12/2014 04:21:46.000 kernel[0]: AppleThunderboltNHI::prePCIWake - power up complete - took 1337 us
12/12/2014 04:21:46.000 kernel[0]: AppleThunderboltHAL::earlyWake - complete - took 0 milliseconds
12/12/2014 04:21:46.000 kernel[0]: Thunderbolt Self-Reset Count = 0xedefbe00
12/12/2014 04:21:47.000 kernel[0]: AppleCamIn::systemWakeCall - messageType = 0xE0000340
12/12/2014 04:21:47.000 kernel[0]: AppleThunderboltNHIType2::waitForOk2Go2Sx - retries = 2