Focus of the CONCERTO activities in the Salburua area is the construction of new buildings. Altogether 42,000 m² in 432 energy-efficient dwellings had been planned, split into two sectors . The first is called “promotion A-31” and comprises two identical groups of three residential buildings each. The total heated area of the 256 dwellings is 22,339 m². Each group will be supplied by the heating energy of a 218 kWth ground source heat pump, 173 m² solar thermal collectors, 27 kWth cogeneration units (CHP) and two high performance boilers with a peak power of 774 kW. Surplus energy from the collectors is stored in a seasonal storage. As the dwellings of A-31 were designed for selling to private people, but there is no demand from the market right now, this task has been delayed. Probably demonstration activities on refurbishment will be performed instead.
The second sector is named “promotion A-32” and represents a building with 176 rented social dwellings (12,549 m² total heated area). The heating energy is supplied by two high performance boilers (peak power of 840 kW) and a natural gas CHP unit (25 kWtherm and 11 kWel). Photovoltaic panels with a total power of 60 kWpeak and a total surface of 430 m² are installed as sunshields above the windows (Picture 1). A wind turbine of 50 kW is planned, but not realized yet. The construction of A-32 started in September 2011 and will be finished by the end of 2013 (Picture 2). One remarkable improvement compared to the original plans is the increased insulation quality of the implemented windows (U-Value of 1.1 W/m2K compared to the benchmark of maximum 2.0 W/m²K).
As the energy system at Salburua will consist of a mixture of renewable and non-renewable energy supply sources and an integrated system for distribution and delivery of heat and electricity to the end-users (micro-grid), an energy management system will be installed for optimal operation (Picture 3). Specification, definition, development and validation of the load forecast module, electrical and thermal consumptions have been performed and validation tests are being carried out. The energy system can be summarized as the following:
- A cogeneration plant (CHP) driven by natural gas (supplemented by peak-load/backup boilers)
- Façade-integrated photovoltaic panels of 60 kWpeak
- Small-scale wind turbines
Research on combined heat and power (CHP)
During 2011 and 2012, TECNALIA – partner in the consortium of the PIME’s CONCERTO project - has specified, defined, developed and validated a module for the economic dispatch of microCHP units, which will be part of the energy management system at Vitoria-Gasteiz. A pilot of this module has been implemented and tested in TECNALIA’s so-called “KUBIK” building (Picture 4). The CHP system used is a “Dachs SE G5.5” with 12.5 kWtherm and 5.5 kWel (Table 1).
Testing was performed in three phases: examining the optimal operation, applying the planned operation to “KUBIK” and collecting and validating the real data. Figure 1 shows the set-up of the test system.
|
Parameter
|
Value
|
Unit
|
|
Thermal power
|
12.5
|
kWt
|
|
Electrical power
|
5.5
|
kWe
|
|
Total efficiency
|
88
|
%
|
|
Volume of buffer tank
|
750
|
litres
|
|
Maximum output temperature
|
78
|
°C
|
|
Minimum output temperature
|
50
|
°C
|
|
Nominal power of tank
|
7.5 – 25.2
|
kWt
|
Table 1 – Technical fact sheet of the used CHP unit
