Project start: 2019
Partner: New housing assistance, factor 10
Project key points:
- iSAtech delivery systems for electricity and water in 42 apartments.
- Provision of water and electricity as an annual budget.
- Costs for electricity and water will be charged over the rent.
- Budget is set according to the number of residents.
- Display of the current and estimated consumption as well as the consumed and available budget via smartphone, website and information terminal in the home
- Warning of budget overruns.
- Credit can be closed in the event of excess consumption.
- Configuration: Networked delivery units in all apartments, central connection to server.
- Networking: iSA bus (wired, RS485) in the building. High reliability and power supply via network.
Displays facilitate energy saving
"In the 42 apartments for people with access difficulties to the housing market, almost all utility costs are billed on a flat-rate basis, including heating and hot water. The flat rate also includes budgets for drinking water and household electricity, which are sufficient if people behave sparingly. A display in the hallway of each apartment informs households about current and past electricity and water consumption, as well as the remaining budget for the current year. Measurement results show that household electricity consumption is 50 percent below that of comparable German households, and heat consumption for heating and hot water is very low. Another positive aspect is that the municipality benefits from the lower utility costs in terms of social services."
https://www.darmstadtimherzen.de/aus-der-stadtwirtschaft/iwu-passivhaussozialplus/https://www.darmstadtimherzen.de/aus-der-stadtwirtschaft/iwu-passivhaussozialplus/
Realized requirements for successful implementation of the prepaid/budget concept:
- Display in the apartment with current balance in euros and kilowatt hours/liters, plus consumption trend and forecasts.
- Simple additional payment possible if the budget is not enough.
- Charging the meter without access to the meter.
- Notification when the remaining balance falls below a certain value, also possible via SMS and e-mail.
- Tariffs and budgets with easy possibility to change if e.g. the occupancy of an apartment or the individual requirements change.
- Easy management of the system.
- Quick overview and evaluation for management.

Display views in the apartment



Approaches to reducing ancillary costs in social housing using the example of the "PassivhausSozialPlus " project: https://www.iwu.de/research/handlungslogiken/passivhaussozialplus/
Displays make it easier to save energy - kick-off of the "local alliance" in Darmstadt: https://www.darmstadtimherzen.de/aus-der-stadtwirtschaft/iwu-passivhaussozialplus/
Paradigm shift in social housing: https://www.neue-wohnraumhilfe.de/nordbahnhof-1/
AFFORDABLE NEW CONSTRUCTION - THE PASSIVHAUSSOZIALPLUS: https://transition-darmstadt.de/Veranstaltung/bezahlbar-neu-bauen-das-passivhaussozialplus/