Submeters to measure AND RECORD energy use

In our project the tenant pays a lump sum for thermal energy use, but pays for electricity based on actual consumption. We therefore cannot achieve the 3 points. We currently do not have sub-meters installed to measure the thermal energy. My question relates the the requirement of the sub-meters to "record" energy use. Can this be done manually or is it necessary for the meter to record the use? If we install thermal meters to get the two points we will still not pay for actual use, so there is little motivation to read these meters regularly.