After an evening of frenetic software installation attempts on Monday, everybody, PC and Mac users alike, became the proud adopters of EnergyPlus, a DOE-based energy simulation freeware. Weighed down by the laptop in my backpack, I still managed a little skip in my steps walking out of the residence this morning: as the program indicated, today is one of the more technical days.
At 9am in our homeroom in BOKU SR6, Prof. Stieldorf laid a general overview on the topic of ‘Energy Balance in Buildings’. Afterwards, Markus Brychta gave a lively presentation under the title of ‘Innovative Cooling Processes’. While the engineers were happily immersed in compressor-condenser cycle diagrams and heat transfer equations, the architects sat with knotted brows as the slides slid by to a halt. Now, someone please stop me before I offend our lovely architect friends with stereotypes in this open-access ‘diary’.
One interesting point that stood out during Markus’ presentation, is the principles of efficient HVAC design (beyond cooling technologies) that could apply to all climatic conditions. For example, the decoupling of ventilation needs and heating/cooling demands, to independently satisfy sensible and latent loads, to oversize ducts for low pressure drop, and not to oversize boiler/chillers for better efficiency. In addition, heat and moisture recovery, smart control and set point strategies can save energy at low added cost during the design of building mechanical systems.
Clearly, I am retelling the technical content here simply to prove that I was awake during the presentation. In fact, I have grown very attached to the coffee vending machine in the break room at BOKU during the past week. Holding a steamy delicious 50-cent-cafe-Macchiato looking out into this beautiful Vienna morning, I wept a single tear as I thought about the inevitability of having to leave it behind when our Vienna stay comes to an end.
The early afternoon session was rather interesting. We conducted several hands-on simulation exercises of a classic shoe-box building using the beloved Google Sketchup and EnergyPlus. Without sinking too deep into the obsession and frustration of energy simulation, most of us were happy with the brief taste of energy modelling and were feeling smug about it.
The following item on the agenda is the visit to Fernwärme Wien district heating plant. I was still deep in thought fantasizing about bringing the coffee vending machine through customs to Canada, when the U-bahn already pulled up in front of the landmark Spittelau plant with its memorable decorative skin and unique architectural style.
Designed by renowned Austrian artist Friedensreich Hundertwasser, the district heating plant was truly impressive. Hidden behind the bold curved enclosure of colourful tiles, the building itself renders one million tons of Vienna’s household waste into heat and electricity every year.
Intrigued by this power plant/garbage damp/rebellious castle, we were then led to the mechanical room. Despite the buzzing noise of pumps and chillers in the background, Alexander Wallisch gave us an informative lecture on district heating and cooling by recovering energy from waste incineration.
In closing, I would like to dedicate today’s log to Wendy, who missed a day due to a little incident that was quickly taken care of by the Austrian health care system and our beloved tutor Maljete.
Text / Photos: Yichao Chen