Your estimated solar photovoltaic (PV) system production is shown in the chart above.

To zoom in on any part of the chart, click and drag over your area of interest. To move the chart data use the controls at the bottom of the graph window.
The chart above shows your system generation compared with your site load.

Sorted Hours
Your load duration curve is shown in the chart above. This chart shows the 8760 hours of load during the year (Load), sorted from highest load to lowest load. This is compared with a sorted load profile after the PV production has have been taken into account (Reduced Load). Any power that is less than zero is excess electricity that is backfed into the utility grid.

To zoom in on any part of the charts, click and drag over your area of interest.
Latitude Longitude State Turbine Type Hub Height Number
Speed (m/s):
Power (kWh):
The above graphs show the monthly average wind speed at your location and the estimated monthly power generated by your wind system(s). To save these results, choose the Export Results button at the bottom right corner of this window.

To compare the amount of electricity your system will generate with your actual load profile, you can upload your unique load profile. A load profile represents the amount of electricty consumed over 1 year on an hourly basis.

The uploaded file must be a comma-separated values (CSV) file and contain only two columns: hour and load.

An example of this format is provided below.


This is the size of your solar panel array in kilowatts. A typical roof-mounted array is 4 kw, which typically corresponds to 32 m2. After drawing your solar array, you may change its size in this box. The value represents the maximum direct current (DC) energy produced by the system.

The derating, or derate factor, represents the amount of electricity lost in the conversion from DC to alternating current (AC) power. The defualt value is 0.8, which corresponds to a 20% loss. IMBY uses this value to calculate the AC energy output of the system.

The tilt angle is the inclination from horizontal (0° = horizontal and 90° = vertical) of the PV array. The table below gives tilt angles for various roof pitches (the ratio of vertical rise to horizontal run) for roof-mounted arrays.

Roof Pitch Tilt Angle (°)
4/12 18.4
5/12 22.6
6/12 26.6
7/12 30.3
8/12 33.7
9/12 36.9
10/12 39.8
11/12 42.5
12/12 45.0

For a fixed PV array, the azimuth angle is the angle clockwise from true north that the PV array faces. The default value is 180° (south-facing) for locations in the northern hemisphere. This normally maximizes energy production. In the northern hemisphere, increasing the azimuth angle favors afternoon energy production, while decreasing the azimuth angle favors morning energy production. The table below provides azimuth angles for various headings.

Heading Azimuth Angle (°)
N 0 or 360
NE 45
E 90
SE 135
S 180
SW 225
W 270
NW 315

This is the year of solar data that IMBY uses to create a production estimate. IMBY uses a modified version of the PVWatts performance calculator that can use a specific year of modeled hourly solar data to estimate your system's solar electricity production. By using a specific year, you can compare your system's output with your actual load profile for a given year.