Halifax Regional Municipality of Nova Scotia, Canada, is the first Canadian city to use an in-pipe hydroelectric generation system within a pressurized water distribution pipeline, according to Halifax Water. On Nov. 13, a 32-kW generating system within a drinking water distribution control chamber for Halifax Water began providing power.

Stakeholders for the Halifax project hope the system will power about 30 homes and produce US$29,000 in revenue annually. Officials said the project cost US$443,000 and Halifax Water; Denver, Colo.-based Water Research Foundation and the provincial government provided the funding.

Halifax Water serves the municipality’s 355,000 residents. The regulated municipality contracted Rentricity Inc., a New York-based renewable energy company, to install the in-pipe system that is rated “safe for drinking water.” The device’s viability for placement in a system from which people consume drinking water is based on Canadian and international safety standards.

According to Rentricity the company designs and installs Flow-to-Wire, their trademarked, unique energy recovery system. “The system harnesses excess pressure within water mains and uses it to generate clean electric power,” said the company. “A single Flow-to-Wire system produces between 30 and 350 kW of clean, renewable, electricity that can then be sold back to the grid.”

On July 7, Standards Council of Canada (SCC) accredited NSF International – a global independent public health organization that writes standards and tests and certifies products for the water, food, health sciences and consumer goods industries – to develop “National Standards of Canada.” NSF International has met SCC’s rigorous program requirements for the accreditation of a standards development organization, according to NSF and SCC.

NSF/ANSI-61

Products sold in North America by manufacturers or developers that distribute water treatment or distribution products are required to comply with “NSF/American National Standards Institute (ANSI) Standard 61: Drinking Water System Components – Health Effects by most governmental agencies that regulate drinking water supplies, ” according to NSF International. The criteria for many water system components include the following:

• Protective barrier materials (cements, paints, coatings)

• Joining and sealing materials (gaskets, adhesives, lubricants)

• Mechanical devices (water meters, valves, filters)

• Pipes and related products (pipe, hose, fittings)

• Plumbing devices (faucets, drinking fountains)

• Process media (filter media, ion exchange resins)

• Non-metallic potable water materials

Micro-turbine devices used for in-pipe hydroelectricity, however, are not new to the U.S.

Boulder, Colo., began installing small hydroelectric systems in its distribution pipelines within the past decade, according to published reports. Other U.S. cities that use in-pipe hydroelectric generating systems include a 30-kW unit in Butler, Penn.; two turbines in the city of Keene, N.H., at 40 kW and 22 kW; and a project in Portland, Ore.

Published reports indicate Lucid Energy has a contract with the Portland Water Bureau to install a 172-kW in-pipe, power producing turbine in the Powell Butte area of Portland. The company said the privately funded, US$1.7 million pilot-project will generate 1,100 MWh hours annually, equivalent to the power use of 150 homes. In September, the company began installing the turbines, and once they are online the expected revenue is US$55,000 during the first year of operation.

