Case Study Introduction  Case Study Conclusions 
Part 1: Resource Process
1. IDENTIFY PROSPECTIVE SITE: Sound of Islay
2. Use ADMIRALTY CHARTS to define:

5. MAPPING
Generate cross section profile to scale in AutoCAD or similar 

Export profile as a bitmap 

Colour code surface roughness 
6. TIDAL DATA
 Using tidal spread sheet insert values for:
 Bathymetry roughness, blockage, meander, irregularity, etc
 Tidal heights over a period of interest for two diametric ports near to the site
 Fig: extracted values from easy tide
7. Tidal spreadsheet generates values for:
 Mean flow rate
 Optimum turbine energy capture
 Simultaneous calculation of Manning’s & Bernoulli nos. to yield friction coefficients if desired
8. VELOCITY DISTRIBUTION SOFTWARE
 Insert coloured bitmap profile into program
 Insert value for slope in stream direction
 Insert values generated from tidal spreadsheet
9. GENERATE VELOCITY DISTRIBUTION FOR SITE
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Part 2: Technology Matching
10. Set a 30m depth limit and subtract inoperable areas from the profile:
 5m from surface
 5m from seabed
11. Using tidal data, generate a frequency distribution over a year of tidal current velocities
12. Find the predominant velocity for the channel profile: 2m/s (from velocity spectral density curve)
13. Find the Cp (efficiency) of each technology and size at the predominant velocity:
14. To calculate the NUMBER of devices that fit into channel.
(This is a function of the area, depth, & number of devices
and is limited by the recommended extraction value (SIF))
 Set spacing distances as follows:
15. LOCATE the devices in the appropriate areas of the velocity profile until space is exhausted
Fig: Three different sizes and spacing for each technology inserted into the available space in the profile
16. Calculate the SIF (Significant Impact Factor) with respect to the velocity
 If SIF limit of 10% is exceeded, recalculate number of devices that can be inserted into channel
17. Calculate the total POWER output over the year using the number of devices, the inflow area, the Cp and the SIF impact on velocity and therefore generate 9 possible options in terms of size, number inserted & power output
16. Assess most suitable technology by considering power output in conjunction with economics & environmental impacts for a particular velocity profile
17. Repeat entire process by considering the power output for another profile the specified distance along the channel
18. Repeat by generating profiles and their potential power outputs along the channel and summing the value to calculate the power output for the entire length of channel
Case Study Introduction  Case Study Conclusions 
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