in the wake of a tidal stream turbine

In the wake of a tidal stream turbine

Stuart Walkers.r.walker@sheffield.ac.uk

tidalsheffield.wordpress.com

Contents

• Background and context• State of the art• Where my work fits in• What I am aiming to achieve• Results so far• Future work

BackgroundEuropean Marine Energy Centre established

First small test machines installedTidal Generation Ltd (TGL) founded

First power provided to UK grid

Large companies begin investingFirst 10MW arrays receive planning approval

Around 25MW UK installed capacityTGL sold to Alstom for £46m

2003

2004

2005

2006

2007

2008

2009

2010

2011

2012

2013

A tidal turbine

30 m200 t1 MW

£8.5m?

Projected contribution to UK grid

Total figure: DECC “Gone Green” projection Tidal figure: RenewableUK Industry report (Feb 2013)

in next

1300% increase

7 years!

UK resource estimate:

32 GW95 TWh/yr(Crown Estate 2013)

20% of our electricity by 2050?

The current state of tidal power

• 20-30 years behind Wind• Test machines in the water• A few small arrays proposed• Huge challenges remain:

– Installation– Cabling– Grid connection– Array layout– Finance

Array layout

My work - Turbine wakes

Key questions

• How much power is lost when one turbine is placed behind another?

OR

• Where should a second turbine be placed in order to minimise the power deficit?

Experimental setup

Experimental setup

Experimental results

Velocity deficit

Velocity deficit

Turbine location

Recovery to 60% (3D downstream)

Eddies generated behind post

Full recovery (11D)

Experimental results

Next steps

• Full turbine data recording (power output)• Tests under a wider range of conditions

Questions?

www.shef.ac.uk/mobileuni27th – 29th SEPTEMBER