SOLAR SIZE A Solar Photovoltaic Design Aid for Windows by Keith Wamsley Copyright 1992 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 the unregistered version of 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. Table Of Contents TOPIC PAGE INTRODUCTION 2 SYSTEM REQUIREMENTS 2 INSTALLATION 2 BASIC FORM INPUTS 2 BASIC FORM OUTPUTS 4 DESIGN OPTIONS 5 FILE MENU 5 OPTIONS - GENERAL 6 HELP MENU 6 CALCULATION BASIS 7 ADVERTISEMENT 8 REGISTRATION 9 Page 1 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. SYSTEM REQUIREMENTS This program will run on any system that is running Microsoft Windows Version 3.0 or later. INSTALLATION There are six files you must 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 VBRUN100.DLL DLL file for Visual Basic Copy VBRUN100.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 BASIC FORM INPUTS When you first start the program you will see the data entry and calculation output form. This is the main form that you will use to interface with all the programs features. The Basic form input is information you provide. They are located on the top left portion of the form. Page 2 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 continous 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 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 lighing 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. MIN OPERATING TEMP DEG F Enter the lowest winter design temperature that the battery will be exposed to. Battery capacity deminishes 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 City Data File option can supply this value for you. See the Options section for more information. 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 reccommended. You should consider weather, critical nature of the load, proximity of maintenace 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. Usually a Lead Calcium battery is used in the Lead Acid family. Page 3 CALCULATE This tells the program to calculate the results based on your input values. If the latitude or longitude was changed then Sun Hours is also calculated. BASIC FORM OUTPUTS These are the values that the program calculates for you based on your inputs. Use these values to chose your perfered 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 degreee 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 characterised 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. ARRAY PEAK CHARGING CURRENT Chose an array or multiple arrays that deliver the required amperage at normal sun intenstity. Be sure the system matches your required system voltage. 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. Page 4 DESIGN OPTIONS 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 or clicking on the Calculate Sun Hours line under the Options menu bar. 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 or the Calculate Sun Hours line under Options. 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 only determine the temperature. This is done with the "Temp Only" option button or the "City Selection, Temperature Only" line in the Options Menu. The City Selection option also supports multiple lists. You may develope regional or special purpose lists. A list is loaded by selecting "City Selection, File Select" under the Options menu. The city data files are ordinary text files with a .CDF extension. You may use any text editor 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. Page 5 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. 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 effected the calculation. OPTIONS - GENERAL BATTERY END OF LIFE FACTOR Batteries gradually lose capacity through out their life. Usually a batteries usefull life is over when its' capacity falls below 80%. The program has a default value of 1.1 to compensate for this effect. This factor is multiplied by this factor to determine battery amp-hour capacity. You may change it to any value between 1.0 and 2.0. 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 type preference 3. City Selection City file 4. Battery end of life factor Selections active at the time of execution of this option are saved. HELP MENU The help menu item provides you with an online help. Click on any item you wish more information on. Page 6 CALCULATION BASIS There are three calculation 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 multipling five factors: Load current, Hours/Day load is drawn, days of backup desired, temperature derate, and end of life factor. Array Angle An easy one. This is latitude plus 15 degrees. 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. Page 7 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 developement and makes me a couple of bucks. 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. Page 8 REGISTRATION: To register send your $20 to: Keith Wamsley 3403 Ft. Richmond Dr. Richmond, Tx. 77469 Please provide your: Name: ________________________________________________ Company: ________________________________________________ Street: ________________________________________________ City: ___________________________________ State: ______________________ Zip: ______________________ Serial Number: ___________________ (from About Menu) Comments: Thanks for your support!!