- Site information
The site I chose is the Eastgate Property, which is located off Sturdy Road in Valparaiso, IN. The most important reason for choosing this site is that this is where I spent my most time during my college life. Another cool thing in Valparaiso is, the four seasons are very distinct, and people can appreciate very different views in the building at different times of the year.
From topography aspect, the site I chose is very flat, which means it’s easier for the construction side. The following is the Google Earth map to show the site picture and a little bit about the building information.
- Climate information
In Climate Consultant, I chose the weather information in South Bend, IN because they are very close geographically.
According to the weather data summary above, I picked the temperature and wind speed to consider about. For temperature, I would consider the dry bulb temperature of the location since it’s the real temperature that people will feel. Overall, there is a relatively big difference between summer and winter. From the table above, the average Direct Normal Radiation in summer is almost twice as much as in winter. Considering the passive design, in summer, we can maximize the usage of solar panels to generate electricity. In winter, considering the situation that the solar energy may not so sufficient, what I would do is to change the orientation of the building facing the south side and use heat absorptive materials in building design, like green roof to absorb more sunshine in order to strengthen the ability to keep warm inside the building.
For the wind design analysis, I found a table from the National Weather Service. In February and March, the average wind speeds are both up to 12mph, which indicates at least half of the time the wind speed is above 12mph. From the table below, the wind type is basically Gentle Breeze or Moderate Breeze. So, wind may not be a big influence factor we can take advantage of.
Cloud percentage may be another factor we need to consider for the efficiency of solar panels. Lower cloud percentage means we can take more advantages of solar energy. We are expecting this situation happens more in cold days.
From the psychrometric chart, 52.3% of energy consummation is from the heating system. That’s a big part. So, we may define this site as a relatively cold area, and we need to pay more attention to heating system passive design for sustainable purposes.
- Conceptual Mass Models
Here, I created two models with different shapes. To keep it simple, the first one is just a very simple block shape building with two stories. The second model is the same shape but has a 40ft x 40ft hollow shape in it. To eliminate the influence of different surface areas, I kept the area of both buildings as 25,000ft2, and dimension of 100ft x 125ft by each floor. The two masses are shown below:
Project 1
Project 2
- Solar insolation analysis
Compare the two different designs, by using Solar insolation analysis, the energy saving for project1 is a little bit higher than project2. From my own perspective, that’s reasonable because in model 2 we actually increased the surface area. For the extra part of area, we need to place more solar panels to take advantage of, which increases the payback years from 11.3 years to 14.5 years.
• Insight analysis to predict the energy performance:
After doing the insight analysis of the two projects, I picked several factors that may affect energy savings.
- Building orientation.
From observation, the influence of building orientation is very small, so, I think that may be because the total solar radiation for a building to absorb is a certain value, which depends on the area of the building and material of the roof. Manufacturer won’t charge more just because of the building orientation.
- Plug load efficiency
Plug load efficiency can highly affect the energy of the building, so, I recommend setting a certain value of electrical load as a regulation to save energy.
- Lighting efficiency.
Lighting efficiency also can have a huge impact on energy saving. People should be able to use sustainable bulbs to achieve 100% light efficiency.
- Solar panels surface coverage percentage
From observation, once solar panels surface coverage percentage is greater than 60%, the impact can be very small. So, 60% of solar panels coverage percentage is what I would recommend.
Overall. we can observe from the analysis result, project 1 is more economic than project 2 in energy aspect. And also from construction side, project 1 is more easy to build. So I would pick project 1 as our final project.
Following are some comparison results:
Overall cost:
Project 1 Project 2
Building Orientation:
Project 1 Project 2
Plug Load Efficiency:
Project 1
Project 2
Lighting Efficiency:
Project 1
Project 2
PV surface coverage:
Project 1
Project 2
- Tradeoffs
The first comes into my mind is we need to optimize the surface area and solar panel area. No matter which factor is too high, it will increase the payback time and cost. If the surface area is too small, even if we have sufficient solar energy to absorb, we still can’t take advantage of it since it’s beyond the ability of solar panels. Another point is the market price of lighting efficiency bulbs is much higher, if we use those sustainable bulbs in our building, the total cost will increase.