The Communications Challenge

Wessex Water is in the process of delivering its largest and most complex project yet - establishing a water supply grid. The £225M, eight-year project involves the construction of more than 200km of new pipelines, 24 new or refurbished pumping stations and 12 new storage tanks ranging from two to eight million litres.

Wessex Water required a cost effective telemetry Supervisory Control and Data Acquisition (SCADA) communications solution to interconnect this vast network of pipelines, pumping stations and reservoirs.

McKelvie Solutions a telecoms system integrator with over 30 years experience in radio and an IP radio solutions specialist, was asked to assess suitable microwave technologies to determine the best solution. The assessment also required consideration of wind and solar technologies for remote site powering solutions.

To meet the communications challenge the following were identified:

• Microwave radio using licensed and licensed exempt spectrum.
• Power requirement of radio solution 24 V DC.
• Near-line of sight operation between some sites.
• Low power consumption as some sites are off-grid. 

Microwave Solution

Following a full assessment of the options available, McKelvie Solutions selected InfiNet wireless radios as the optimum solution to meet Wessex Water's requirements. The InfiLink 2X2 LITE operates in different frequency bands providing the user with the flexibility to choose other bands. this is beneficial to the user as it gives them the choice of opting for licensed exempt bands if there are cost implications to the licensed band. The InfLink 2X2 LITE has a low power consumption of 7 watts which was particularity important for Wessex Waters requirements, as the solution will be used in remote sites running off batteries powered by wind turbines and solar power. It also uses a DC-to-DC POE injectors which could be integrated with existing site power requirements of 24V DC. These factors made it the ideal solution for Wessex Water SCADA Network.

McKelvie Solutions provided site surveys, conducted radio Path Profile Analyses (PPA), installed and commissioned approx. 200km combined point to point links over three counties. The radio links range from 2km up to 36km between sites providing on average between 9Mbits/s to 26Mbits/s using a 5MHz channel bandwidth. 

The microwave IP broadband network has been designed as a ring network with each radio configured as a router using Open Short Path First (OSPF). This assures resilience if a link fails as telemetry traffic is routed in the opposite direction. There is a spur from the ring network to Wessex Water's control room which can monitor SCADA network.

McKelvie Solutions has also installed off-grid power solutions using LE-300 small wind turbine from Leading Edge Turbines, solar PV panels and seven days autonomous battery supple at remote relay sites.

 The Result

Wessex Water now have a wide area microwave radio network, supplied by McKelvie Solutions, that can operate in remote communications environments and is cost effective compared with other telecoms solutions. The low power consumption of InfiNet combined with the wind turbine supplied by Leading Edge Turbines creastes a sustainable , low emissions solution. The microwave network is future proofed as there is spare capacity for new IP applicaitons such as IP CCTV.