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Solar Position, Sun Charts, Solar Climatic, Collector Orientation...

Tools that give sun position, climatic data for solar design, and radiation on a solar collector.

Tools to design window overhangs.

Directory of page:

Solar Site Survey

Collector Orientation

Solar Position, Radiation and Climatic Data

Window Shading and Overhang Tools

Wind Resource

PV System Performance

Solar Site Survey
Solar Site Survey...	If you are going to do a solar project, you need to do a Solar Site Survey to make sure that your site gets enough sun during the right times of year to make the project work. This free and simple survey only takes an hour and is fun and educational. Its a must do for any type of solar project!
Effect of Collector Orientation On Performance
Effects of Tilt and Azimuth On Annual Incident Solar Radiation For the United States Locations Craig Christensen and Greg Barker www.solar.fiu.edu/PDFs/pdfs/34892-31.pdf	This paper provides a very simple set of contour plots that show optimum collector orientation, and the performance effect for deviations from optimal. Covers only the US, but the general relationships would be useful elsewhere. Some limitations -- read the cautions in the paper.
Radiation On Collector Gary	A tool that provides radiation levels on a flat plate collector for sunny days as a function of collector location (lat and long) and orientation. Use to answer questions like what if I can't aim my collector due south?
Solar Position, Solar Radiation, Solar Design Climatic Data
Sun Charts http://solardat.uoregon.edu/SunChartProgram.html	A Sun Chart for your area is a must have tool to determine how much of the time sun will shine on your collectors. See site survey for how it works.
Climate Consultant, UCLA Energy Design Tools http://www2.aud.ucla.edu/energy-design-tools/	Climate Consultant is one of the UCLA Energy Design Tools. It provides a variety of ways to visualize weather for a specific location. Weather data files are available for hundreds of locations. This is a brand new version, and is very easy to use. "It graphically displays climate data in either metric or imperial units in dozens of ways useful to architects including monthly bar charts, timetable charts, and psychrometric charts, sun shading charts, and sun dial charts." One of the most interesting charts is the Psychrometric chart with overlays that show the design strategies (e.g. passive solar, evaporative cooling, ..) will work for the location in question.
Solar Time to Local Time -- Solar Noon, NOAA www.srrb.noaa.gov/highlights/sunrise/sunrise.html	A helpful calculator that gives sunrise, solar noon, and sunset in local time for any location and any date. Helpful in many situations, including finding true south at your location.
More Solar Radiation and Weather Data Sources NOAA http://lwf.ncdc.noaa.gov/oa/ncdc.html NOAA CLIM20 Weather Summaries by City NOAA year to date degree days NREL (and other) Solar Radiation and Climatic Data http://rredc.nrel.gov/solar/pubs/redbook/ Total and diffuse radiation or building surfaces: Solar Radiation Data Manual for Buildings Typical Meteorological Year weather files http://rredc.nrel.gov/solar/old_data/nsrdb/tmy2/	NOAA provides a variety of weather related products and data. The CLIM20 product provides pretty detailed historical weather summaries for many US towns. It includes temperatures, precip, and heating and cooling degree days. Lots of good data. NOAA year to date degree days provides deg day totals for the current year. Updated each week. NREL Redbook: Average weather conditions and solar radiation of collectors at various orientations for many US cities. Based on 30 year weather records. Try downloading the pdf version for your state. NREL Bluebook: The Solar Radiation Manual for Buildings gives total and diffuse radiation on S, N, E, W and horizontal surfaces. TMY weather files give provide typical hour by hour weather files to provide weather input for simulations.
Energy CAP Free Degree-Day Weather Tools http://www.energycap.com/weather/	A nice set of free web tools that give heating and cooling degree day information for 1200 locations. Provides historic, current, and even near term degree day forecasts. Very easy to use. Note that a default balance point temperature is 55F is used -- you can change it to the more usual 65F if you wish.
Degree Days.net -- Worldwide Degree-Day Tool http://www.degreedays.net/	Nice tool for heating or cooling degree-day summaries for locations around the world. The data comes from Weather Underground stations, so it may be easier to find a location near you.
NCDC Degree-Day Maps Heating and Cooling Degree Day Maps Heating Degree Day Map of US (130K) Cooling Degree Day Map of US (100K) National Climatic Data Center http://lwf.ncdc.noaa.gov/oa/ncdc.html	Heating and cooling degree-day maps for the US.
Surface meteorology and Solar Energy NASA http://eosweb.larc.nasa.gov/cgi-bin/sse/sse.cgi?na+s01#s01	Solar radiation and solar geometry data from derived from satellite observations. Provides data for anywhere in the world. Provides solar parameters for solar thermal, PV, solar cooking, etc. based on 10 year history for your exact location.
Radiation On Collector Gary	A tool that provides radiation levels on a flat plate collector for sunny days as a function of collector location (lat and long) and orientation. Use to answer questions like what if I can't aim my collector due south?
Window Shading and Overhangs
Sustainable By Design Solar Tools http://www.susdesign.com/design-tools.html	Some very well done (and free) tools for designing overhangs, determining sun position, ... The overhang design tool is very good.
Designing Shading Overhangs with Google SketchUp http://www.sketchup.com/ Caution: The free version of SketchUP does not allow you enter your latitude. For the sun model they assume a latitude of about 40 degrees North. This means if your latitude is near 40 degrees, the shadows will be accurate. However, errors in the sun's elevation and azimuth will increase as you go north or south of 40 degrees. Within the US (latitude 25 to latitude 50), the elevation angles can be off by up to about 12 degrees. Azimuth angles (particularly for south areas) can be off by as much as 40 degrees.	SketchUp is a free 3D drawing tool from Google. In addition to being exceptionally easy to use as a general purpose drawing tool, it offers a built in sun. You can easily draw a wall with a window and overhang, and play the sun over it for various times of day and times of year. One of the nice features is that the wall can face any direction, and could even be tilted. The window and overhang can also be any geometry you like. Windows can be set back into the wall, and vertical shading fins would also be easy to do. It could also be used to layout your whole house (with trees and sunspaces), and see how the sun plays over it. The small example overhang in the picture was done in less than 5 minutes after taking only 10 minutes to go through the little beginners tutorial. If you have been turned off in the past by drawing programs that claimed to be easy to learn, give this a try -- its amazing.
Wind
Got Wind? -- How to use the Wind Resource Atlas of the United States	The Wind Resource Atlas of the United States will give you a rough idea if you are in a locations with wind potential -- here is how to use it.
PV
PVWatts -- A Performance Calculator for Grid-Connected PV Systems From NREL http://rredc.nrel.gov/solar/calculators/PVWATTS/ This is a really useful tool.	An easy calculator you can use to find out how much power you will get from a PV installation in your area. It calculates PV system performance based on hour by hour records for sun in your area. Version 1 is very easy to use, and works worldwide. Version 2 allows more detailed inputs, but seems rather complex and puzzling at times to me.