This case study looks at Wessex Water’s requirement for interconnection between their remote water pumping and reservoir sites in Dorset and the off-grid power solution specified and supplied by Leading Edge Turbines. An LE-300 small wind turbine was mounted on top of a tower and along with solar PV panels, it provided power for the microwave communications network.

Wessex Water required a cost effective solution to interconnect their remote water pumping and reservoir sites within the Dorset and Wiltshire areas. They needed the ability to send telemetry data to these sites, some of which were off-grid, to control water levels. Their analysis included a full range of telecoms technologies including microwave, fibre, satellite, ADSL and unlicensed low bit rate UHF radio.

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

To meet the communications challenge, the following was required:

• Microwave radio using licensed and licensed exempt spectrum.
• The radio solution also needed to operate at 24V DC and near-line of sight.
• Low power consumption as some sites are off-grid.

The Solution:

After a full assessment of the options available, McKelvie Solutions selected InfiNet Wireless. The InfiLink 2×2 LITE operates in different frequency bands. This provides the user with the flexibility to choose other bands if there are cost implications to the licensed band and to opt for licensed exempt. The InfiLink 2×2 LITE has a low power consumption of 7 watts which was particularly 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 injector which could be integrated with existing site power requirements of 24V DC. These factors made it the ideal solution for Wessex Water.

Wessex Water required links to be set up between Dorchester and Winterbourne Abbas and between Blandford and Sturminster Marshall. For the challenging near line of sight link between Dorchester and Winterbourne Abbas, McKelvie Solutions installed a trial InfiNet Wireless link at 3.6GHz. This solution gave a getter E.I.R.P then license except and with the lower frequency band was ideal for the challenging 5km link. The link between Blandford and Sturminster required connecting via a rebroadcast site at Houghton Clump and for this line of sight trial, McKelvie Solutions selected 5.8GHz licensed exempt for the 13km and 11km links. Using this hybrid network, an engineer only needs to be trained on one radio solution due to the flexibility of InfiLink 2 x 2 LITE. This lessens the training burden for the user, making it a more user friendly option.

For the trial McKelvie Solutions also installed an off-grid power solution using the LE-300 small wind turbine from Leading Edge Turbines, solar PV panels and 7 days autonomous battery supply at Houghton Clump relay site. The off-grid power solution was specified and supplied by Leading Edge Turbines and has successfully powered the remote site’s two radio outdoor units.

The Result:

Wessex Water now have a microwave radio network, provided by McKelvie Solutions, that can operate in hostile communication 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 creates a sustainable, low emissions solution. The microwave network is future proofed as there is spare capacity for new IP applications such as IP CCTV.

Read the Wessex Water case study on the InfiNet Wireless website and learn more about the InfiNet equipment within the microwave IP broadband network.