iSAtech water GmbH
Consumption Overview Water budgets, electricity budgets, and monitoring in social housing

Project start: 2019

Partner: Neue Wohnraumhilfe, Faktor10

Project cornerstones:

  • iSAtech BMS Control Units for electricity and water in 42 apartments
  • Provision of water and electricity as an annual budget
  • Costs for electricity and water are billed via the rent
  • Budget is determined according to the number of residents
  • Display of current and expected consumption as well as the consumed and available budget via smartphone, website, and information terminal in the apartment
  • Warning if budget is exceeded
  • Credit can be added in the event of excess consumption
  • Configuration: Networked iSAtech BMS Control Units in all apartments, central connection to server
  • Networking: Wired, RS485; high reliability and power supply via network

Displays make it easier to save energy

In the 42 apartments for people with difficulties accessing the housing market, almost all ancillary costs are charged via flat rate, including heating and hot water. The flat rate also includes budgets for drinking water and household electricity, which are sufficient if people behave economically. A display in the hallway of each apartment informs households about current and past electricity and water consumption and the remaining budget for the current year. Measurement results show that household electricity consumption is 50 percent lower than comparable German households, and heat consumption for heating and hot water is very low. Another positive aspect is that the local authority benefits from lower ancillary costs in terms of social benefits.

https://www.darmstadtimherzen.de/aus-der-stadtwirtschaft/iwu-passivhaussozialplus/

Realized requirements for successful implementation of the prepaid/budget concept

  • Display at home displaying the current credit balance in euros and kilowatt hours/liters, as well as consumption trends and forecasts
  • Simple additional payment possible if the budget turns out to be insufficient
  • Charging the meter without access to the meter
  • Notification if the remaining credit falls below a specific value, if required via SMS and e-mail
  • Tariffs and budgets with easy switching options, e.g., if the occupancy of an apartment or individual requirements change
  • Simple administration of the system
  • Customized analysis view to give the management a quick overview of the budgets of all tenants

Display Examples