Start Me up Tuesday: What Is a Neighborhood and When Is It Considered Sustainable?

Our next Start me up Tuesday on February 27, 2024 in the small ceremony hall of UAS Technikum Wien is all about Sustainable Districts. Researchers, teachers, start-ups and large companies will present their visionary concepts and pioneering ideas for sustainable districts. We spoke to David Sengl, who works in teaching and research in the Climate-Fit Buildings and Districts field of expertise at UAS Technikum Wien, in the run-up to the event.

What is meant by “sustainable districts”? What is a district and when is it considered sustainable?

David Sengl: Sustainable districts are a collection of different buildings that use local resources as energy-efficiently as possible and at the same time offer the people who live there the opportunity to meet their needs in a space-saving way without compromising future generations’ way of life.

Neighborhoods can be found in a wide variety of designs. For example, there are neighborhoods that are primarily used for one purpose, such as residential or office space. However, there are also neighborhoods that cover a mixed form and in which offices as well as apartments and stores are located. The latter has the advantage that people who live in or near the neighborhoods can use their infrastructure and synergies are created between the different forms of use.

The question of when a neighborhood becomes sustainable is difficult to answer. Precisely because sustainability includes a wide variety of aspects such as greenhouse gas emissions, social integration, biodiversity and economic efficiency, and because neighborhoods exist in a wide variety of forms, it is not possible to make a quantitative statement in this regard. Rather, the neighborhood must adapt to the local conditions and enable people to meet their energy needs using locally available energy sources. Nevertheless, it is important to make the social goals for climate neutrality quantitatively assessable and to break them down into concrete fields of action and goals. Here, the neighborhood approach offers the opportunity to introduce important measures at an early stage through concrete specifications for energy and greenhouse gas balances as well as green space design and to open up scope for action that would otherwise simply be “plastered over”. To this end, several approaches are being pursued for sustainable districts, such as the plus-energy district, the 15-minute city or the aspern klimafit building standard developed especially for the Urban Lakeside, in order to address all these aspects as far as possible. However, as this is a very complex topic, projects in this area are still in the development phase and a general definition of sustainable districts is being researched.

The demand for urban living space is constantly increasing. What role can the use of (new) technologies play in making living in a limited space as sustainable as possible?
David Sengl: Especially in the Vienna area, where demand is growing and local resources are limited, creating living space is one of the biggest hurdles. In order to expand living space as much as possible, it is not expedient from a sustainability perspective to expand the outlying districts, but also to revitalize vacant buildings and renovate and densify old buildings.

Of course, new buildings cannot be completely avoided, as they are often more energy-efficient than renovations and the neighborhood design is more flexible, which also contributes to sustainability. Nevertheless, revitalizations and renovations help to reduce the grey energy generated during the construction process of buildings and make them as sustainable as possible using the latest technologies.

For example, compact drilling equipment can help to access existing courtyards and create deep probes for the use of geothermal energy. The use of heat pumps and photovoltaic systems also serves to reduce energy demand through the flexible use of energy by converting electricity into heat and creating heat for the living space in times of overproduction of PV. This means that districts with different uses in particular can greatly reduce their energy requirements by using the energy where it is needed. For example, the PV surplus at lunchtime, when the majority of the population is in the office, can be used in these areas and the waste heat from the commercial areas in the morning or evening hours can be used to heat the living areas. In this way, a combination of building types can be used not only to save space, but also to save energy.

Is it enough to equip buildings with the latest technologies to create a sustainable future?
David Sengl: No. Technologies make a significant contribution to the energy efficiency of buildings, but the best technology is useless if it is not used.

User behavior and people’s acceptance play a key role here. Renewable energies are so-called volatile energy sources. This means that energy production fluctuates greatly depending on the environment. For example, a photovoltaic system only produces energy when there is solar radiation and users can only use it at this time. If the energy requirements of the neighborhood mainly take place outside of these production times, photovoltaics will only have a very small impact on sustainability. However, if the users accept the volatility and change some of their habits, for example by programming the dishwasher to use energy at lunchtime, PV has a much greater impact. This also applies to larger consumers such as heat pumps. If the residents accept small temperature reductions at night, a synergy between the generation by the PV and the consumption by the heat pump can be optimally utilized and a building can be operated sustainably while still maintaining the usual standard of comfort.

So no, technology alone is not enough for a sustainable future, the people who use it must also always be considered.

More on this at the event, where David Sengl will be joined by other experts such as Judith Klamert-Schmid (FH Technikum Wien, Head of Department Industrial Engineering) Tanja Spennlingwimmer (AWS, Head of Entrepreneurship / IP / Deep Technology) and Johann Kucsera (Schneider Electric).

Find out more about the event here: (Page in German)

www.technikum-wien.at/events/start-me-up-tuesday-sustainable-districts/