Stage 1:
The two evaluation metrics: 1. Construction Cost
The total construction cost of the building. Both floor areas at various levels and gross surface area are taken into consideration. Floor areas have different cost at different levels (beams, columns, and floors), while surface cost remain constant (glass curtain wall).
- Operation Cost
The total cost of operation of this building. Three factors are taken into consideration: HVAC cost (related to solar insulation), regular cost (lighting and other electricity usage), and roof solar-panel electricity regeneration.
Reasons of choosing these metrics:
- Cost is the essential factor in the planning and designing phase of a building project.
- Construction cost and operation cost are the two major cost in the full life cycle of the building, so evaluating these two metrics can help us do better LCA on the building project.
Dynamo main node logics for the evaluation: Construction Cost:
Operation Cost:
Result Sheet:
Stage 2: Scheme: Using weighted combination score of surface efficiency, gross volume, construction cost and operation cost to do the single-objective optimization.
Weights:
Surface efficiency: 1
Gross volume: 0.5
Construction Cost: 1.5
Operation Cost: 2
Reason:
- Surface efficiency and gross volume are the general factors to be taken into consideration when planning a building project. Gross volume is less important, so the weight of it is lower.
- Construction cost and operation cost have larger weights because they are closely related to sustainability, which is vital in Dubai with limited resources. Operation cost has the highest weight is due to this reason as well.
Result sheet:
Finally the 350 height, 60 degree rotation plan is suggested to be the best among all 12 because it has better operation cost due to the shading effect of its obvious rotating angle.
Answers to points to ponder:
- Do the new evaluation metrics that you’ve designed capture the meaningful differences between the building form alternatives?
- What other metrics would be useful to compute to help understand and make the case for which alternatives are truly better than others?
- What overall strategy do you feel best captures the relationship between the evaluation metrics?
- What propelled the recommended alternative to the top of the list? the 350 height, 60 degree rotation plan is suggested to be the best among all 12 because it has better operation cost due to the shading effect of its obvious rotating angle.
- Are there important nuances or tradeoffs that got lost is the single evaluation?
I think so, because they take sustainability into consideration, which I believe is important.
I believe other metrics related to sustainability would be useful, including end use of energy, total electricity consumption, etc.
Overall strategy: Sustainability is more important than building form geometry, function of the building, and appearance of the building. Operation phase is more important than the construction phase.
I believe in Dubai, the buildings to be built around Burj Khalifa Tower are all auxiliary buildings to subplot the Burj Khalifa Tower. Thus the appearance, view, and building form is not so important. Also, the total population of Dubai is also not very high. (most people are tourists). However, resources are limited in Dubai, due to the limits in drinkable water, construction labors and materials, and high temperature. Thus, sustainability, especially the one in the operation phase, should be the most important factor compared to other factors, I believe.
There could be. Since the weights are chosen subjectively, and there are still lots of aspects that are not considered (including the comfort of people inside the building, appearance, usage of building), a number of things could get lost in the single evaluation, which indicates the limit of this evaluation method.