From 1982 to 1987 the company’s predecessor Nova Energy conducted two tests and developed 4 working prototypes. Most of this work was conducted with research grants from the National Research Council of Canada. Through the late 1990’s and early part of this millennium the company developed and designed its tidal bridge technology. From 2005 to 2007 the company conducted an extensive testing program in the tow tank at the University of British Columbia, modernizing the technology through the use of computational fluid dynamic models that were validated through this testing.
The Canadian National Research Council Hydraulics Laboratory in Ottawa constructed a stainless steel water flume 4 feet deep by 9 feet wide with flow straightening vanes in the flow delivery and a flow control sluice gate at the outflow end. A pump drew water from a tank under the laboratory floor and the water level and flow rate in the flume were controlled by the pump and a hydraulically controlled sluice gate opening. A substantial bridge structure was built across the top of the flume to carry various model turbines and their support structures, and a variable speed gearbox drive which allowed the turbine rpm to be varied while driving a fixed rpm induction generator. A dynamometer in the turbine rotor drive shaft measured rpm and torque, current meters measured upstream and downstream velocity and resistance type probes measured head difference across the turbine.
20 kW Free Stream Turbine B1
A contract was awarded to build a 20 kW Vertical Axis Hydro Turbine in early 1983, for installation in the Seaway at Cornwall in Ontario, and to connect it to the Niagara Power Corporation grid. The site was not very suitable, being too shallow and having a low current velocity. Nevertheless we went ahead with a difficult installation and the unit performed quite well, producing up to 20 kW to the grid. The generator was a vertically mounted induction unit driven by a variable speed gearbox. The generator alone had an efficiency ranging from 26% to 52.5%. The mechanical and electrical efficiency of this system (carefully established on an NRC dynamometer) was in the order of 45%, so that the turbine alone was actually producing about 45 kW. The B1 unit was then turned over to the Design Authority and was tested for two seasons by NRC. Once enough data was obtained the turbine was stored and eventually discarded.
100 kW Hydro Dam turbine B2
In 1984 a 100 kW restricted flow Vertical Axis Hydraulic Turbine was built and mounted on a head pond control dam. The machinery included a 120 H.P. - 3 phase - 600 volt induction generator driven by a five banded V belt and a set of pulleys which could be changed to vary the turbine to generator RPM. The gearbox was a 120 H.P. right angle helical unit with a 13 to 1 ratio driving a counter shaft which included a hydraulic disc brake, a torque and RPM meter, pillow blocks and provision for interchangeable pulleys. The rotor arms and blades were extruded aluminum with welded in place cast aluminum attachment fittings. The turbine was connected to the Nova Scotia Power Corp. grid and had the usual motor overload relays and disconnects and other safety systems.
4 kW VEGA 1 in the Gulf Stream
Also in 1984 a Texas businessman was enthusiastic about using a vertical axis turbine to capture the energy in the Florida Gulf Stream, to produce electrical energy for the production of hydrogen and oxygen by electrolysis to fuel the Challenger space shuttles. He called this idea VEGA (Venturi Energy Generating Apparatus) and funded Nova Energy to produce a vertical axis turbine model to generate power at a depth of 200 feet, to avoid super tankers. The design used new aluminum extruded blades and the optimum duct contours with a 4 feet dia. rotor with four 4 feet long blades and duct dimensions to suit. The gearbox and generator were installed in a stainless steel tube with sealing end caps and sophisticated drive shaft and armored power cable designs. Electrical power was produced from the Gulf Stream for the first time on April 15th 1985.
5kW Tor 5
In the spring of 1987 the TOR 5 (5kW) run-of-river unit was constructed and tested at the entrance to Porters Lake in Nova Scotia. This unit was mounted on a retractable drum on a standard 18 foot fiberglass boat hull which provided floatation, a self-mooring capability, space for auxiliary equipment and maintenance personnel, trailering capability, and self-launching and propulsion to the selected site.
Collaboration with the University of British Columbia
In 2006, Blue Energy signed a collaborative research agreement with the University of British Columbia to develop computer simulations of the previous turbine tests with the NRC. The collaboration also developed an experimental towing tank program intended to provide data from a physical model to validate the numerical simulations. The group tested a physical model in August 2006, November 2006, and again in September 2007 at the Oceanic towing tank, showing both numerical codes to be representative of the experimental data. The numerical work thus provides a significantly more cost and time effective method of predicting blade performance and loading, optimum ducting shape, and scalability when compared to cost intensive experimental testing.