The rate versus time can then be the subject of whatever calculation the user chooses, for example:

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1 Using Neptune Planner Plus to Export Tidal Rates to Excel These notes are intended to assist the interested user in exporting predicted tidal stream rates into a spreadsheet for the estimation of tidal energy at a location. The exported data is not fit for any particular purpose and if used then this is done so at the users own risk. The data produced from this program cannot be further reproduced in any form or included on any reports, publications web sites, communications unofficial or official including s or lectures without the authors written permission. It is unlikely permission will be denied but Neptune retain the right to impose this restriction on this programs output. History The program is intended for the navigator of leisure boats to calculate the effects of the horizontal tidal movement on their proposed passage and calculate a course to steer to minimise these tidal effects and head them to their destination in an efficient manner. The program emulates the mariners Course To Steer calculation. Because of the continued debate of tidal versus wind power the authors have added a small routine to assist someone to reasonably estimate for the purposes of the debate, the amount of tidal power available and to help determine the location and size of the turbine array. This is not intended as a design tool. Method in a nutshell Horizontal movement of water in this program is determined from historical observations of the sea at a particular location. The observations are then tabulated into a data block known as a tidal diamond and the figures are tied to the time and height of high water at a convenient port. Neptune planner has at its heart a tidal prediction algorithm and a database of tidal diamonds and so for any given Tidal Diamond for any given time the rate and direction of the tidal flow can be estimated. Tidal diamonds by their nature are only approximate and many factors affect their values, do not expect the data to be mathematically smoothed. The predictions in the program have been used successfully by many thousands of Yachts men over the years and are suitable for that purpose. This utility calculates the tidal rate and direction at a selected tidal diamond location for the date selected for the program. The day s data can then be exported as a comma separated file which many spreadsheet programs can easily import. The rate versus time can then be the subject of whatever calculation the user chooses, for example: Energy = ½(M x V 2 ) in Joules. Also, as a reminder, 1 Watt is 1 Joule per second. Also note that that the density of seawater is approx In your spreadsheet with the predicted velocity of the seawater it becomes a relatively simple task to work out the energy available and the times during the day the energy will peak. Additionally note that maximum energy will occur during spring tides (New and Full Moon) and minimum energy is at neap tides.

2 Tidal heights predictions are useful for those considering the argument of tidal gate type of power generation,. The tidal height prediction part of the software allows the user to readily see high and low water times and also the tidal range of the day. The data within the program is only available for the United Kingdom.

3 Quick start The program comes with a sample chart of the English Channel. The program runs in demonstration mode for 14 days after installation. Use after that date program usage is only possible on purchase. Additional tidal areas for around the UK can be added for a cost of between 20 and 75 depending on the cartographic detail required. Theses areas can be purchased through our website. Neptune pays royalties to The United Kingdom Hydrographic Office for the use of the Tidal Data and as such no more data can be released without payment being made. Full program help is available either as a PDF a shortcut which can be found in the Program group under the start button or on the desktop (Particularly for Windows 8 users). The program help is also available from the Help menu. It is recommended that for tidal energy application Neptune Outline Chart Portfolios be used, that is, unless you intend to go to sea with the package in which case UKHO or Imray charts should be considered. From the opening screen, if you agree with the conditions, press the Accept Button and you will be presented with a chart. The example chart is the English Channel Central Part (Outline only) with a sample of tidal diamond locations. The magenta arrows represent tidal flow for the chosen time(derived from Tidal Diamonds) and the grey polygons are the locations of ports for which tidal heights are available. (Coloured polygons represent waypoints that are used by navigators). Zooming and panning is easily achieved using the mouse wheel for Zoom in and Zoom out or with the arrow keys. Number keys are also used by for zooming (1= 10% zoom, 2 = 20% etc and 0 = 100% zoom). Alternatively there is a zoom to rectangle button on the toolbar.

4 Exporting the tidal flow rates. Zoom to a tidal diamond of interest, position the cursor at the base of the magenta arrow and RIGHT click the mouse. From the pop-up menu select Tidal Stream Details. A window appears with the details of the diamond and also shows the rate prediction. (Remember this software is intended for the Diver or Sailor and so additional information is being presented here which may be of no interest to the tidal modeller). Click on the date in the right column (eg 14 April 2013 in the above screen) and another screen will be displayed

5 As the mouse is moved across the curve the line above the graph shows the predicted time, rate and direction of flow. This data can be exported to a comma separated variable file by selecting the file menu on the screen A standard windows Save As dialog is presented and the user can save the curve as a.csv file (comma separated variable file). The default location is in the folder NeptunePlus that has been created by the software in the users Documents folder

6 Importing the data into Excel. It is useful if your PC has CSV files associated with being opened by Excel or whatever spreadsheet you are using. If not you will have to use the Get External Data facility within your spreadsheet. 1..Open your Documents folder and look for the folder NeptunePlus (or wherever you have saved the file). If your file associations allows you double click the.csv file The spread sheet will appear with the data contained in separate cells. Column 1 contains the Time in HH:MM format, Column 2 contains the rate in knots Column3 contains the direction in True with 0 being north and West being 270. Column 5 contains the time in 24 hour Decimal format eg 19.5 being 19:30 Column6 contains the rate in metres per second (derived as rate in knots x Column 7 contains the prediction date and 8 and 9 contain the latitude and longitude(-ve = west)

7 Tidal Height Menu Operation The Tidal Prediction software can be selected from the menu or for a specific port by placing the cursor on the icon and double clicking or F1 on the keyboard. The program will display, the name of the Home Port, the home ports predicted tides for the day and the tidal curve for the day. Examining the plot for the curve which shows a red vertical line (time line) set at the PC's time. If the mouse pointer is moved into the graph area the time line will follow the mouse, the height, time and rate of rise or fall of the tide will change as the cursor is moved. Also displayed is the tidal range for the day and Spring to Neaps indicator. To freeze the values click the mouse button at a required time, to unfreeze the display click the mouse again. Times All times of predictions are given at the standard time kept at the place; for example, in the British Isles the time used is Universal Time (GMT), from the Configure Menu > Program Options the Results Adjusted for Summer Time can be set.

8 NOTE: Our stand is that energy is available from Wind, Solar and Tidal forces. Just because we provide this utility for tides does not mean we have any particular point of view about one method having merit over another. We just like tidal theory and its applications. Experimenting with the data is up to the user but the following need to be taken into account in your calculations: Area of any turbine, The Kinetic energy available Remember when dealing with Metres 2 to multiply the mass of water by 1000 as there are approx 1000Kg in 1metre cubed of sea water. Turbine efficiency must be included, this will be between 40-70% as a reasonable figure (depending on design). There is a nice page available on the internet discussing Turbines and kinetic energy. wdstudio.net/gulfstreamturbine/kinetic.htm

9 Acknowledgements of data (UKHO ) Belgium Denmark Note: Inside Skagen the sea level is dominated by meteorological factors; the astronomic tide plays only a minor role, therefore only ports from along Danish west coast are included. France Germany Note: The Tidal department of the BSH (Bundesamt fûr Seeschiffahrt und Hydrographie) do not use harmonic constants, the data used has not been verified recently and may give some discrepancies when compared with the official German tide tables. The Netherlands Rijkswaterstaat Netherlands Note : In the Netherlands the data for analysis is based on observations from 1991 to The data given for Roompot are outside of the Storm Surge Barrier in the Oosterschelde. Portugal Spain United Kingdom NEPTUNE Navigation Software PO Box 5106, Riseley, Berkshire, RG7 1FD Telephone website sales@neptunenavigation.co.uk

10 English Channel Tidal Diamond Distribution NB Rates are typical of the state of tide existing when the images were captured.

11 West Coast of United Kingdom and Ireland Tidal Diamond Distribution

12 East Coast United Kingdom -Tidal Diamond Distribution