The city of Valladolid, located in central Spain with a Mediterranean continental climate, participated in the DIRECTION project that aimed at demonstrating how the use of very innovative and cost-effective energy-efficient technologies can lead to the achievement of very-low-energy new buildings. This objective, along with the effective adoption of low-energy buildings, was achieved by switching to a model whereby energy efficiency provided value to the market and represented an attractive asset across the whole of the value chain.
This innovative approach was demonstrated in the new building CARTIF III, which has 4 075 m² of floor space and will be used for CARTIF Technology Centre research activities, with both offices and test facilities.
Demo Site Expected Impact
*The KPIs for the new building are compared with the baseline of a reference building.
As a result of the energy-efficient and renewable energy sources interventions, the consumption of both thermal energy and electricity are cut in half compared to the reference building. The reference building in this region has 75 kWh/m2/yr as a total final energy consumption whereas the CARTIF III achieved a monitoring consumption of less than 35 kWh/m2/yr. Therefore, in comparison with business as usual, the final energy savings amount to 53 %.
As a result of the interventions undertaken, a total annual amount of 277 MWH/yr of primary energy can be saved in comparison to the reference building. This reduction on primary energy is translated into 101 tonnes of CO2 (25 kgCO2/m²/yr) that can be saved in comparison to the reference building. In relative numbers, this is an emissions reduction of 70 %. The monitored CO2 emissions amount to 46 tonnes per year (11 kgCO2/m²/yr).
Energy efficiency in buildings
- High-performance new buildings
- The building envelope minimises thermal energy demand
- The building envelope minimises electricity demand for lighting through glass walls and louvre blinds that improve solar gain
- High-efficiency lighting
- Waste heat recovery: mechanical ventilation and heat recovery, with a free cooling system for the entire building that allows a considerable reduction in cooling requirements
- Building integrated renewable energy sources
- Photovoltaics: 45 kWp photovoltaic, which allows a contribution of 15 kWh/m²yr
- Heat pumps
- Geothermal heat pump with seasonal performance for the office area, which transfers energy to and from the ground to ensure balance. The annual thermal requirement to heat this area therefore is zero.
Energy systems integration
- Biomass boiler
- A very-high-performance biomass boiler (> 90 %) provides all the necessary thermal energy for the industrial buildings and the domestic hot water
- Building energy management system
The investment costs associated with energy-efficiency and renewable energy sources interventions amount to EUR 544 660. The largest share of this budget goes on the installation of shading devices (EUR 155 000) and the geothermal system (EUR 135 000). The energy cost savings are EUR 18 181 per year with the reference building as a baseline.
Based on the calculated energy savings, the payback period for design and monitoring data is determined to be more than 30 years. This result considers a discount rate of 3 % and an inflation rate for the energy carriers of 3 %. On the one hand, this value is higher than the average payback period of 30 years for eligible costs related to energy efficiency measures as stated in the European Commission decision from 2013. On the other hand, the longer payback period reflects the core energy efficiency measures with a longer life cycle, such as energy-efficient insulation and other facade parts.