














                               SOLAR  SIZE  V1.1




                     A Solar Photovoltaic System Design Aid



                                  for Windows





                                      by
						



                                 Keith Wamsley












                        Copyright 1993 by Keith Wamsley
                             All Rights Reserved















                            Software Agreement


        This program is distributed as Shareware it is not Free
        Software.  It is not public domain.  It is copyrighted.
        You are granted permission to use Solar Size for a trial
        period of 30 days.  After that time you must register to
        continue use.  Registration is a mere $20.00 so please
        do so.  A form is provided at the end of this document.

        I would also appreciate any comments you might have or
        if you find any bugs.  If used, you will get a free
        upgrade.

        You are given permission and encouraged to copy and
        distribute this software if: 1) All files are included in
        the distribution, 2) No modification of any kind is made
        to any of the files, and  3) No fee is charged for the
	software.







	Keith Wamsley hereby disclaims all warranties relating to 
        this software, whether expressed or implied, including
        without limitation any implied warranties of
        merchantability or fitness for a particular purpose.
        Keith Wamsley will not be liable for any special, incidental,
        consequential, indirect or similar damages from the use of
        this program.  The person using the software bears all risk
        as to the quality and performance of the software.





        Windows, Visual Basic, and VBRun200.DLL are trademarks and
        copyrighted by Microsoft Corp.

















                            Table Of Contents



           TOPIC                                              PAGE


        SECTION 1 - GENERAL

          INTRODUCTION                                          2

          SYSTEM REQUIREMENTS                                   2

          INSTALLATION                                          2

        SECTION 2 - THE MAIN FORM                               3

          FORM INPUTS                                           3

          FORM OUTPUTS                                          4

          FORM OPTIONS                                          5

          FILE MENU                                             6

          OPTIONS - GENERAL                                     6

          HELP MENU                                             7

        SECTION 3 - LOAD CALCULATION FORM                       8

          FORM INPUTS                                           8

          FORM OUTPUTS                                          9

        SECTION 4 - HYDROGEN EVOLUTION FORM                     10

        SECTION 5 - OTHER                                       11

          CALCULATION BASIS                                     11

          BATTERY TYPE                                          11

          ADVERTISEMENT                                         12

        REGISTRATION                                            13









                                   Page 1

                       SECTION 1 - GENERAL


INTRODUCTION:

        This program will calculate the required battery size, solar array
        size, and array angle for installations requiring a solar power
        solution.  It has the power and flexibility to adapt to your
        particular design needs.  Solar Size has built in sun intensity
        and temperature data to ensure a reliable, properly designed
        installation.


SYSTEM REQUIREMENTS

        This program will run on any system that is running Microsoft Windows
        Version 3.x.


INSTALLATION

        There are six files you should have to run the program:

		SOLAR.EXE		The main program

		SOLAR.INI		Holds your configuration options

                MAJORUS.CDF             Data file of major US cities

		SOLAR.LDF		Winter peak sun hours data file

                USERDOC.TXT             This file, User Documentation

                VBRUN200.DLL            DLL file for Visual Basic


        Copy VBRUN200.DLL to your \Windows\System directory.  If you already
        have this file you do not need to copy it again. The remaining
        files should be copied to the directory of your choice.  They
        must all be in the same directory.

        To install in a Program Manager group:  Select the group where
        you want the program to reside.  Select "File" from the Program
        Manager menu bar then select "New".  Select "Program Item".  Select
        "OK". The Program Item Properties box will now open.  On the
        Description text box, type "Solar Size".  On the Command Line text
        box, type in the path you copied the files to and add Solar.Exe
        This line should look something like: C:\Solar\Solar.Exe if you
        used a directory named "Solar" when you copied the files.


   






                                Page 2

                        SECTION 2 - THE MAIN FORM


        This is the primary form you will use to interface to the program.
        It can accept your input data and present your project's requirements
        back to you.  All other forms are enhancements and options to
        assist your use of the program.  This form will automatically
        appear whenever you start the program.

FORM INPUTS

        
        LOAD IN AMPS:
    
        Enter the total load amps that the system will provide to all
        loads at nominal system voltage.  Use an average value for all
        periodic loads.  Example:

        A load is composed of two components: a 0.25 amp continuous load
        and a 2.1 amp radio that is on 2 minutes every 30 minutes.  The
        Load Amps value to use is:

		0.25 + 2.1 * 2 / 30 =  0.39 Amps

        You can let the program calculate this load for you by checking
        the "Calculate Load" box and filling in the load profile data on
        the "Load Calculation" form.  See the Load Calculation form section
        for more details.

        HOURS / DAY LOAD IS SUPPLIED
		  
        Enter the hours per day that the load above is powered by the system.
        Usually this is 24 hours except for lighting or navigational aids
        type of loads. This value times the Load in Amps must equal the
        total system amp-hour load in a 24 hour period.

        This data is supplied for you if the "Calculate Load" box is
        checked.

	MIN OPERATING TEMP DEG F

        Enter the lowest winter design temperature that the battery will
        be exposed to.  Battery capacity diminishes with temperature.
        This value is used to calculate the battery capacity required at
        the worst conditions.  Use good judgement; use of a 100 year spot
        low is unrealistic and will result in a high battery cost.  The
        temperature used should be sustained for several hours.  If you
        use a short backup time then you should be more conservative
        (use a lower Temperature) than if you use a long backup time.

        The City Data File option can supply this value for you.  See the
        Options section for more information.






                                Page 3

        DAYS OF BACKUP REQUIRED

        How many days of battery backup do you require?  This assumes
        that the battery is providing all electrical energy to the load.
        A minimum of five days is recommended.

        You should consider weather, critical nature of the load, proximity
        of maintenance personnel, etc., in determining this value.

        WINTER PEAK SUN HOURS

        The average number of hours in the winter that the solar panel is
        providing it's full output.  Be sure not to use annual average
        sun hours.  The program can determine this value for you if you
        know the site latitude and longitude.  See the Options section
        for more information.

        BATTERY TYPE

        Batteries vary in recharge efficiencies and low temperature capacity
        changes.  Hence the program must know the type of battery you are
        using.  Most Gell Cells are the same as the Lead Calcium type.

        CALCULATE

        This tells the program to calculate the results based on your
        input values.


MAIN FORM OUTPUTS

        These are the values that the program calculates for you based on
        your inputs.  Use these values to chose your preferred vendors
        equipment.  The outputs are located on the lower part of the main
        form.

	BATTERY TEMPERATURE CAPACITY
	
        This is the resulting battery capacity at the design winter
        temperature conditions at the site.  It is expressed as a percentage
        of the batteries 77 degree F capacity.  This value is used in the
        calculation for the required battery size to ensure the specified
        backup time in the winter.  It is displayed as information to
        show the temperature effect on the battery.

        REQUIRED BATTERY SIZE

        This is the battery's required  Amp - Hour rating at 77 Deg F you
        will need.  Chose a battery or multiple batteries to obtain this
        capacity.  Solar applications are characterized by a slow drain,
        therefore use the battery manufactures' long term (usually 24 hour)
        capacity rating.

        Chose a battery designed for Solar applications.  This application
        is not typical of engine starting or float charged stationary
        battery systems.  The solar battery is guaranteed to discharge
        every 24 hours.  Proper battery type selection will ensure longer
        life and better performance.

                                Page 4
        ARRAY PEAK CHARGING CURRENT

        Chose an array or multiple arrays that can deliver this
        amperage at normal sun intensity.  Be sure the system matches
        your required system voltage.  This value should be considered
        the minimum array rating for a system.

        If the array will be partially shaded,  coated, not orientated due
        south, or otherwise impaired; the required rating may need to be
        increased.  Areas prone to long periods of cloudyness may also
        need additional capacity.

	PANEL ANGLE TO HORIZONTAL

        This is the angle the array should be mounted.  This will
        permit optimal sun collection in the winter when the sun is
        lowest in the sky.  The more north you are the higher the
        required angle.  The array should be pointed due south.


DESIGN OPTIONS - Main Form

        There are two main options available over and above the basic
        form entry methods.  These methods assist the user in obtaining
        the winter peak sun hours and the minimum temperature for the site.

        CALCULATE SUN HOURS

        You may chose to let the program calculate the peak sun hours
        based on the site's longitude and latitude.  This option is
        activated by clicking on the "calculate" option button in the
        Select Sun Hour Entry Method box.

        Once chosen, enter the sites longitude and latitude, then press
        the "Calc Sun Hours" button.  The sun hours will be placed in
        the Winter Peak Sun Hours text box.  You may switch back to a
        manual entry at any time by clicking the "User Input" option
        button.

        Most all good road maps have the Longitude and Latitude printed
        on them.  Look hard at the map edges, as it is usually in small
        print.  The Rand McNally Road Atlas shows this data.

	CITY SELECTION

        The city selection box allows you to pick from a list of cities
        and the program will determine the minimum temperature, latitude,
        and longitude values to use.  You may chose to allow this feature
        to determine the temperature only, location only (latitude and
        longitude), or both by selecting the appropriate option button in
        City Selection Box.







                                 Page 5

        The City Selection option also supports multiple lists.  You may
        develop regional or special purpose lists.  A list is loaded
        by selecting "Change City File" under the Options menu.

        The city data files are ordinary text files with a .CDF extension.
        You may use any text editor (like Windows NotePad) to create or
        modify the lists.

FILE MENU
	
        The file menu allows you to save and recall all the data on a
        specific site.  The default extension is .SDF for Site Data File.

	NEW

	Clears all text boxes in the form.

	OPEN

	Recalls a file from disk and places the data on the form.
	Any existing data on the form is overwritten. 

        SAVE
		
        Saves all form data in the current file.  The current file is
        shown on the end of the title block.  If there is no current file
        then the program defaults to the Save As function.

	SAVE AS

        Allows you to save all form data under any file name in any directory.
        You would use this option to save a new sites data to a new file.
        This file name becomes the current file.

        PRINT

        The print option will give you a print out of all site data inputs
        and calculated outputs.  Execution of this option calls another
        form that allows the input of company name, site location, project
        name, and project number.  The print out will automatically print the
	current date.  

        If you used the city selection option, the chosen city will show in
        the site location text box.  You may change the entry to anything
        you wish without effecting the calculation.  You may also chose to
        print the load profile data from the Load Calculation form and/or
        the Hydrogen Evolution data.

OPTIONS MENU

	BATTERY END OF LIFE FACTOR

        Batteries gradually lose capacity throughout their life.  Usually
        a battery's useful life is over when its' capacity falls below 80%.
        The program has a default value of 1.1 to compensate for this effect.
        The battery capacity is multiplied by this factor to determine
        required battery amp-hour capacity.  You may change it to any value
        between 1.0 and 2.0.

                                Page 6
        SAVE CONFIGURATION

        This features saves your current options so they are automatically
        used the next time the program is started.
	The options saved are:
		
		1. Sun Hour Entry Method
                2. City Selection data preference
		3. City Selection City file
		4. Battery end of life factor
                5. Battery Type

        Selections active at the time of execution of this option are saved.
	

HELP MENU

        The help menu item provides you with an on line help. Click on any
        item you wish more information on.  Help is also context sensitive,
        simply press the "F1" key and the help screen for the in focus
        control will appear.  There is a help menu for the Main Form, Load
        Calculation Form, and Hydrogen Evolution Form.




































                                Page 7

                       SECTION 3 - LOAD CALCULATION FORM

        This form will calculate the equivalent amp and time required by
        the main form.  You can enter up to eight individual loads of
        varying characteristics.  It is not necessary to use this form,
        but it does provide a simple method for multiload applications.
        You may directly enter the data on the Main Form when the
        "Calculate Load" box is not checked.

FORM INPUTS

        LOAD IN AMPS

        Enter the load current for each load in amps.  Make sure you are
        using the load that the battery will see, not the output of a
        DC to DC converter for example.

        TIME ON

        Enter the time the load is drawing current ("ON") for each cycle.
        The value goes in the text box on the left.  The time units are
        selected from the list box.  One entry in the list box - "Cont."
        stands for continuous.  Select this if the load is on continuously.
        All other time data for that load is filled in automatically if
        this selection is made.

        CYCLE PERIOD

        The cycle period is the time the load is in one turned on and off
        cycle.  This cycle may or may not repeat, that is determined by the
        Time Active values.

        Example:  A navigation flashing light is turned on for 5 seconds
        then is off for 10 seconds.  The Time On is 5 Sec, the Cycle Period
        is 15 Sec.

        TIME ACTIVE

        This is the total time in one day that the load is active, either
        cycling or continuous.  Another way of looking at this is that this
        value is equal to the number of On - Off cycles per day times the
        cycle period.  In the above example if the light is turned on
        only at night the Time Active might be 14 Hours.  For a
        continuous load this would be 24 Hours.  The value here is per day
        so values greater than 24 Hours are not allowed.

        The following relationship must be true for valid time entry:

          Time On < or = Cycle Period < or = Time Active < or = 24 Hours









                                Page 8

FORM OUTPUTS

        EQUIVALENT AMPS

        This is the average current for your loads that flows for the
        equivalent time.  In other words: if all your loads were replaced
        by a single load that draws constant power for the equivalent
        time, this would be it's current draw.  If the "Calculate Load"
        box is checked on the main form, this value is placed in the
        "Load in Amps" entry box on the main form.

        EQUIVALENT TIME

        This time is simply the longest time specified in the "Time
        Active" column.  It becomes the basis for calculating the
        Equivalent Amps.  If the "Calculate Load" box is checked on the
        main form, this value is placed in the "Hours / Day Load is
        Supplied" entry box on the main form.


COMMANDS BUTTONS: CALCULATE AND CANCEL

        Both Outputs are calculated only when the "Calculate" button is
        pressed.  Pressing "Cancel" does not result in any calculation but
        simply returns you to the Main Form.  You may press "Cancel" after
        pressing "Calculate" as a quick way to return to the Main Form.

        The "Calculate Load" check box does not have to be checked to perform
        this calculation.  If not checked the calculated values will be
        calculated and shown on the Load Calculation Form but the "Load
        in Amps" and "Hours / Day Load is Supplied" boxes on the Main Form
        will not be changed.  The values shown on the Main Form are the
        ones used in the final Solar Array and Battery calculations.

























                                Page 9

                  SECTION 4 - HYDROGEN EVOLUTION WINDOW

        The act of charging a battery results in the release of Hydrogen
        gas.  Hydrogen is a very light flammable gas (remember the
        Hindenburg?).  Usually in Solar applications the amount of gas
        generated is so small that natural ventilation will keep the
        gas below it's lower flammable limit.  The calculation here is
        the worst case calculation.  This occurs when the battery is fully
        charged; when the battery is accepting a charge the amount of
        hydrogen released is much less.

FORM INPUTS

        CHARGE CURRENT

        This is the current in amps that goes to the battery.  If the full
        rated output of the solar array can go to the battery, use that
        value.  The type of charger, your load, and array rating will
        determine the actual net current going to the battery.  If a
        conventional battery charger was used, the "float" charge current
        value would be used.

        As an approximation, the program places the calculated peak required
        array current in this box for you.  You must substitute a value
        that represents your final design actual to obtain an accurate
        calculation.  This would be the float charge rating or Array rating
        minus load current if a shunt type or no regulator is used.

        NUMBER OF CELLS

        This is the number of cells that make up the battery.  Usually counting
        the number of water filling caps is equal to the number of cells.
        Lead acid batteries require one cell for every 2 volts of system
        voltage.  This would be 6 cells for a 12 volt system.  NiCads require
        one cell for every 1.2 volts of system voltage.

FORM OUTPUTS

        HYDROGEN EVOLUTION

        This is the amount of hydrogen produced in cubic feet per hour in a
        fully charged battery at your input conditions.  Hydrogen is a
        flammable gas and caution must be exercised.  See comments above.

        FRESH AIR TO DILUTE

        This is the amount of fresh air from ventilation that is required
        to keep the hydrogen from becoming a flammable concentration.  This
        amount of air keeps the mixture too "lean" to burn.  Note that this
        air make up rate will keep the ventilated area safe but the area
        immediately around the battery may have a flammable concentration.
        Care must be taken to keep ignition sources away from the battery.

        Hydrogen is much lighter than air and diffuses rapidly.  Ventilation
        should be provided in the higher regions of the building to prevent
        trapping of hydrogen gas.  Most Solar applications result in very
        small amounts of hydrogen generation.  Usually natural building
        infiltration will provide adequate ventilation.

                                Page 10
                               SECTION 5


CALCULATION BASIS

        There are three calculations performed once all the data is entered
        and Calculate is pressed.

        Solar Array Size

        The array is sized so that during the winter peak sun hours all
        the energy taken from the battery during "dark" hours is replaced
        plus fully powering the load.  Batteries have a recharge efficiency;
        that is only a portion of the energy delivered to a battery is
        stored.  This factor is taken into account.

        Naturally there are very few average winter days. Hence on some
        days the battery will not be fully recharged.  There should be
        enough above average days to recover from the very cloudy ones.
        The number of battery backup days is the safety against long periods
        of cloudy days.  That is why 5 is the recommended minimum.


	Battery Size

        The battery size is calculated by multiplying five factors:  Load
        current, Hours/Day the load is supplied, days of backup desired,
        temperature derate, and end of life factor.

        
        Array Angle
                                                
        An easy one. This is latitude plus 15 degrees.  The array face
        should be oriented due south to maximize winter performance.

        Minimum Temperature

        In additions to the calculations, you may be interested in where
        the minimum temperatures in the city data file comes from.  The
        source is the ASHRAE 1985 Fundamentals Handbook.  The numbers
        used are the 99% values.  Simply stated: during the months of
        December, January, and February the listed temperature should be
        equaled or exceeded 99% of the time based on historical records.


BATTERY TYPE

        Designers often ask what type of battery should I use?  Everyone
        seems to have their favorite.  Unfortunately there is no easy
        answer...it depends.  Here are some factors to keep in mind:

        NiCads lose less capacity in colder temperatures than lead-acids,
        but have a lower recharge efficiency.  Hence you may be able to
        use a smaller battery but have to use a larger solar array.
        NiCads have a longer life but cost more than lead-acids.



                                Page 11

        Among the lead-acids, the Lead Calcium is the usual winner.
        This battery uses very little water and is widely available for
        solar applications.  ALWAYS be sure to use a battery designed
        for solar applications.  An automotive battery from K Mart will
        not give satisfactory performance.


INSTALLATION CONSIDERATIONS

        All electrical installations must be installed utilizing good
        engineering practices.  This includes compliance with the
        National Electric Code.  Article 690 specifically covers Solar
        Photovoltaic Systems.  Article 480 (Storage Batteries) and 250
        (Grounding) are also revelant.

        Since most solar power installation tend to be remote, pay
        particular attention to all details that will promote reliability.
        This includes: isolating the battery from temperature extremes,
        preventing corrosion, protection of wiring and terminations,
        location of the solar panel (shading, coating, etc.), and accessibility
        for maintenance.



ADVERTISEMENT

        Shareware is a distribution method, not a type of software.  You
        get to tryout the software before you pay for it.  Load it up
        and run it like crazy for 30 days.  If you don't like it, delete
        it from your machine.  If you do like it, register it.  Pass it
        on to anyone who might have an interest in it.  Please distribute
        all files in the distribution set.

        Registration encourages further development and makes me a
        couple of bucks.  There is an amazing amount of development
        time that went into this program.

        Registration for you eliminates the registration message, and
        allows us to notify you of any upgrades.  It should also give
        you a warm glowing feeling of using legitimate software.

        Do you have special requirements or customization needs?  Let
        me know, we can probably work something out.

        Any comments or suggestions would be greatly appreciated.  You may
        reach me by mail at the address on the registration form or on
        Compuserve at 72427,400.











                                  Page 12

       REGISTRATION:

        To register send your $20 to:

                Keith Wamsley
                3403 Ft. Richmond Dr.
                Richmond, Tx. 77469

        Please provide your:

                Name:        ________________________________________________
                
		Company:     ________________________________________________
                
		Street:      ________________________________________________
                
		City:        ___________________________________
                
		State:       ______________________
                
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                Version:     ______________________

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                (from About Menu)



        Comments:















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