The Alden Research Laboratory (ARL) in the US is to begin testing a prototype of its revolutionary fish-friendly hydro turbine in a laboratory – with real fish.

The lab has received US$5M from the Department of Energy (DOE) to run the tests as part of the government’s Advanced Hydropower Turbine Research and Development Programme.

A smaller sum will go to a consortium led by Voith, which has been investigating the fish impact of existing turbine designs in terms of fish passage, and formulating improvements that can be implemented as part of an upgrade.

ARL, in a joint venture with Concepts NREC (formed by the merger of Concepts ETI and Northern Research and Engineering Corporation) has designed a runner with only three blades to reduce the fish impact of the leading edge of the blade. To compensate for the loss of one of its blades, the turbine has an extra-long runner to extract the energy of the water. The blades are wrapped around the central hub in a corkscrew shape to gradually reduce the pressure and minimise sudden changes in flow velocity that could injure fish.

Theoretically, the turbine will allow 100% fish passage, according to David Tuft at the national-hydropower-association (NHA). ‘The tests are a big step forward,’ he adds. ‘Until now the programme has been concentrating mainly on the fish side of things – behaviour, biology injury and physiology and so on.’

If the turbine is to reach the market, it has to combine its environmental effectiveness with a very small efficiency penalty. ARL claims that this is ‘a few per cent’, but only the tests will prove this claim.

The DOE programme has continued since 1994, although it was ‘hanging by thinnest of threads for a while, appropriating less than US$1M one year,’ Tuft said. Even this year’s US$5M is insignificant, considering the high cost of the research and the fact that the DOE’s budget for research into renewables and energy efficiency is around US$35M. Most of this goes towards solar and wind technologies. ‘Hydro is a renewables stepchild in a way,’ says Tuft. ‘Although the consequences of running short on hydro are now being felt in places where hydro is a significant part of the energy portfolio,’ he said in reference to the electricity crisis in California.

Spiralling power prices in California, combined with the success of ARL’s fish-friendly turbine trials, could rejuvenate hydrotechnical research in the US. ‘I’ll be interested to see what happens under the new administration,’ says Tuft. ‘We’re hopeful of a new and greater impetus on hydro R&D. On the campaign trial President Bush was very enthusiastic about hydrotechnology.’