Clima displays hourly Global and Diffuse Horizontal Solar Radiation values for a typical day for each month.

Typical daily graphs showing the amount of energy gained from the sun have many uses, such as:

• design the building with a passive approach, to control solar gains and reduce energy consumption (allow solar gain during months of heating demand and block them during periods of cooling demand, see for reference the degree days);

• manage the direct solar gain through the glass, to evaluate solar shading devices (most useful in locations with high temperatures and a strong direct component);

• manage the indirect solar gain transfer into the building with a time shift, exploiting the thermal mass, heating thick walls or concrete floors, or designing special rooms adjacent to the main spaces that rely on convection to transfer the heat, such as sunroom or Trombe wall;

• evaluating sustainable renewable energy solutions such as solar thermal or photovoltaic panels.

The integral of the curves in the graphs is the total energy (in Wh/m²), supplied by the sun. Be careful in considering the different types of solar radiation.

• Global Horizontal Irradiance (GHI) is the total irradiance from the sun on a horizontal surface. It is the sum of the Diffuse Horizontal Irradiance and the Direct Normal Irradiance, projected onto the horizontal plane using the solar zenith angle (z).

• Diffuse Horizontal Irradiance (DHI) is the radiation that arrives from the entirety of the sky dome, except the solar disc. Is the radiation that has been scattered by molecules and particles in the atmosphere. It is measured on a horizontal surface

• Direct Normal Irradiance (DNI) is the measurement of the intensity of sunlight on a surface perpendicular (normal) to the sun, as such, in very clear sky conditions and low solar altitudes, the Direct Normal Irradiance can be higher than the Global Horizontal Irradiance.