Gas metering in flats poses a logistical problem for meter reading as each individual flat needs to be metered and read a number of times per year. To expidite the reading process the gas meters can be colocated in a basement or access cupboard, but this requires extra gas piping to be routed to individual flats from each meter thus incurring extra cost during the build.
To reduce costs, several blocks of flats have been built with a main gas pipe routed through the building and a meter installed in or close to each flat. However, the meters are no longer in close proximity and take a lot longer to read manually, thus incurring extra costs at the reading collection stage.
We suggested to the customer that Installing a mesh network to gather the readings would not only allow them to speed up the data collecting procedure, but also allowed them to record a much larger number of meter readings and enable them to profile the customers' usage patterns to a much higher degree than before.
Phase 1
An existing gas meter design was retrofitted with ISM RF hardware and an existing mesh networking stack was used to form the communications. The first phase of the design required all of the meters to form a mesh network with an aggregator at road level that could be read from a handheld device. This allowed someone close to the building to retrieve the readings without having to access the building. The gas meters were battery powered for safety reasons and the aggregator mains powered to allow them to easily collect the readings and be ready to transmit them to the handheld device when needed. 
Phase 2
The second phase of the project was designed to enable automatic collection of the data without the need of the handheld device. A GSM module was added to the aggregator to allow the meter readings to be sent over the GSM network to a central server where the readings from several aggregators was collated and could be displayed for analysis.