4.2 “Da geht no was!“ – optimising building utilities

Partner: Municipal Department 25 (MA 25) – Technical Urban Renewal

The project “Da geht no was!” (which translates roughly as “There’s room for improvement!”) focuses on the savings potentials of building utilities.

In addition to thermal-energetic refurbishment, optimising building utilities is key for enhancing energy efficiency and, hence, reducing the cost of space heating. Moreover, it is frequently possible to implement such measures for relatively little money.

However, if utilities are not optimised, the theoretical energy savings calculated before practically refurbishing a residential building often cannot be attained. The project “Da geht no was!” developed implementation-oriented solutions to remedy this situation.

There may be many different reasons why building utility optimisation is sometimes overlooked. In many cases, existing heating systems are not comprehensively renewed, and interventions for individual flats are either not implemented at all or only half-heartedly. This, too, has many different reasons. Some tenants or landlords / landladies may refuse such measures. Disagreements may arise between flat owners in condominiums, complicating the implementation of optimisation measures. Even if subsidies are in place, obstacles arise when some stakeholders are unable or unwilling to bear the cost. In particular, the operative heating system often is not consistently monitored after renewal.

“Da geht no was!” is based on findings established by the EU-funded project “Smarter Together” in ’s 11^th municipal district Simmering (www.smartertogether.at).

For a total of five residential buildings of varying age and with different heating systems (two properties owned by Wiener Wohnen, two owned by ÖSW, one owned by BWSG), three separate studios specialising in building utilities analysed the status quo and developed concepts to boost building utility efficiency.

Outcomes

The studies indicated six measures that are not tied to individual flats but can be implemented in any existing building to improve the efficiency of its heating system:

1. Reduction of connected load in buildings supplied with district heating

2. The contractually agreed connected load influences the billed costs.

3. Often, renegotiating tariffs does not make economic sense, since new supply contracts may entail less favourable terms and conditions.

4. Adaptation of heat curve

Hydraulic balancing

• Costs are strongly dependent on the specific building and its hydraulic system and may range from Euro 100 to Euro 1,000 per flat.

• Insulation of fittings and distribution pipes

• Switch to high-efficiency pumps

• Installation of thermostatic valves

• Reduction of flow temperature after thermal refurbishment

If these six measures are implemented, energy savings of 5% to 40% can be achieved. The implementation of the measures identified requires varying levels of (financial) commitment. For example, insulating fittings or adjusting the flow temperature are methods that offer a very good cost-benefit ratio. Conversely, hydraulic balancing often proves less cost-efficient.

However, one challenge lies in finding expert professionals able to implement these measures, as they may require specialist know-how.

Information sheet "Da geht no was! Optimierung von Heizungsanlagen im Bestand" (873 KB PDF)

Perspectives:

The potential implementation of these measures is currently being evaluated by all owners. Above all the financing of the various interventions still constitutes an obstacle. Since recently, Kommunalkredit Public Consulting (KPC) is also funding building utility optimisation in multi-apartment buildings.

Information: a link about subsidies for heating system optimisation in multi-apartment buildings (German) can be found here.

https://www.umweltfoerderung.at/privatpersonen/heizungsoptimierung-mgw

Further recommendations were analysed by the project partners:

• Building utility optimisation is an issue that should be increasingly promoted vis-à-vis associations, chambers and platforms.

• A list of competent enterprises able to handle the planning and implementation of projects for building utility optimisation should be compiled.

• A dedicated training centre for heating engineers is needed to combat the shortage of skilled personnel (e.g. a specialised college for heating engineers in ).

• Reducing the connected load of district heating systems should also entail financial benefits (supply contracts with Wien Energie).