# Daylighting and Energy Modeling

Dear All,

I’m doing my master study of how to determine the optimum window opening ratio (office space) using typical materials (glass and wall properties) for a single climatic location. the study will include how a proper window opening size can provide a good daylight and minimizing the usage of artificial lighting during most of the day times, in the same time i believe it can minimize the HVAC energy required to cool down overheated spaces that are a result of using excessive window openings.

For now i’m using LB+HB to study this model and i would love to get some feedback from expertise who went through similar process and advise with useful tips that can help me on this topic.

There are many different ways this can be approached. It also depends upon which qualities of light measurement you wish to use as a control. As a starting point, I recommend establishing an ideal daylight factor or illuminamce value that you desire during hours of operation. Then set up a honeybee recipe that can measure the light value during the desired period. You could use something rather standard from LEED or Illuminating Engineering Society.

From there create parametric geometry of a wall and opening of glass in Grasshopper, assuming your geometry is rather simple. Allow the opening to be variable with slider inputs. Then use a genetic algoritihm component, such as galapogas or octopus, to find and identify the ideal geometry.

Once working, you can then likely introduce an additional aspect of energy measurement and route that into the genetic algoritihm as an equally weighted value.

This would enable you to generate daylight value maximized (most often periods it hits a bench mark) with least amount of thermal energy needed.

General comment, but I believe provides some good seeds for proceeding based on experience.

Thanks dustin taking the time to respond on the topic,

your way of approach is the one I’ve already set to follow it make sense. and systematic.

and actually maybe i forgot to explain this what i’ve already started to build, my test is on office space that i’m looking forward to experiment. The light value that i’m looking for is between 300 to 500 lux max on the work surface. then i built a parametric office space that i can modify by slider input, and now i’m working on to use genetic algorithm to find ideal window opening size with optimum day light value and eventually less energy consumption. but i’m having hard times to figure out how i can get accumulative or average daylight value by setting specific opening ratio each day rather than each hour, cause it will take a lot of time to study daylight value for every single hour of each day in a year then compare it to other day values. and after that how i can compare that daylight value along with energy consumption is it by heat gain and heat loss or rad temp or cooling requirement … which one can give better indication of energy use for comparison ?

thanks again