Do we need to convert the sensor data?

[henry quach]

Hi all,
As i am currently designing the system to send the sensor data from GPY to AWS via LTE-m. I got the data, for example,
temp: 25
temp: 26

I can send these data straight to AWS

tempreading = uniform(20.0,25.0)
mqttc.publish(topic, tempreading, qos=1)

but reading thru some projects, they has changed the data from float to bytes like this:

tempreading = uniform(20.0,25.0)
temp_pack = struct.pack('d', tempreading)
mqttc.publish(topic, temp_pack, qos=1)

My question is that is it necessary to do the convert in terms of energy and memory efficiency?
Sorry if the question sounds dumb but as I could not find the decent answer. Thank you all.